esalq course on models for longitudinal and incomplete
TRANSCRIPT
ESALQ Course on Models forLongitudinal and Incomplete Data
Exercises
Geert Verbeke & Geert Molenberghs
I-BioStat
Katholieke Universiteit Leuven & Universiteit Hasselt
ESALQ Course, Piracicaba, November 2014
Contents
1 Growth curves 1
1.1 Description of the Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.3 Elements of Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3.1 Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3.2 SAS Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.3.3 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2 Growth Data 19
2.1 The Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.2 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.3 Elements of Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.3.1 Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.3.2 SAS Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.3.3 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
3 Mastitis in Dairy Cattle 30
3.1 The Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.2 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.2.1 Missing Data Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.2.2 Intraclass Correlation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.3 Elements of Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
i
CONTENTS 2
3.3.1 Data Manipulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.3.2 Datasets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.3.3 Model Formulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3.3.4 Intraclass Correlation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
4 Age-related Macular Degeneration Study 50
4.1 Description of the Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
4.2 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
4.3 Elements of Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4.3.1 Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4.3.2 SAS Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
4.3.3 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
5 Blood Pressure Data 171
5.1 The Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
5.2 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
5.2.1 Dataset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
5.3 Elements of Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
5.3.1 Basic Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
5.3.2 Raw Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
5.3.3 Covariance Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
6 Marital Satisfaction Data 184
6.1 Description of the Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
6.2 Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186
6.3 Elements of Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188
6.3.1 Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188
6.3.2 SAS Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
6.3.3 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
Dataset 1
Growth curves
1.1 Description of the Data
Goldstein (1979, Table 4.3, p. 101) and Verbeke and Molenberghs (1997) have analyzed growth curves of 20pre-adolescent girls, measured on a yearly basis from age 6 to 10. The girls were classified according to the heightof their mother (small: < 155 cm, medium: 155-164 cm, tall: > 164 cm). The individual profiles are shownin Figure 1.1, for each group separately. The measurements are given at exact years of age, some having beenpreviously adjusted to these.
The aim of the analysis is to study growth in schoolgirls and to investigate the relation of this growth to theheigth of the mother.
growthgv.sas7bdat
height : response, measured in cm
child : child identification number
age : age of the child at the time of the measurement
group : factor defining the groups ( 1: small mother, 2: medium mother, 3: tall mother)
References
Goldstein, H. (1979) The Design and Analysis of Longitudinal Studies. London: Academic Press.
Verbeke, G. and Molenberghs, G. (2000) Linear Mixed Models for Longitudinal Data. New York: Springer.
1.2 Questions
1. Fit a full multivariate model (unstructured mean, unstructured covariance matrix). Parameterize the meanin the following two ways :
1
DATASET 1. GROWTH CURVES 2
Figure 1.1: Heights of Schoolgirls. Growth curves of 20 school girls from age 6 to 10, for girls with small,
medium, or tall mothers.
(a) age group age*group
(b) age*group, no intercept
Compare the results, and interpret the parameter estimates obtained under both parameterizations.
2. Simplify the mean structure, assuming height to increase linearly as a function of age. Parameterize themean such that the estimates for the intercept and the slope of each group separately is immediatelyobtained. Interpret the obtained results.
3. Use an F -test to test whether the three groups have equal average slopes. Can this also be tested using alikelihood ratio test ?
4. Estimate the three pairwise differences of average slopes.
5. Fit a linear mixed model, assuming linear average evolutions, and including random intercepts and randomslopes for time.
6. Compare the model with a model with the same mean structure but unstructured covariance matrix, usingthe LR test statistic as well as information criteria.
7. Compare robust inference for the mean structure to naive inference.
1.3 Elements of Solution
1.3.1 Programs
1. Full multivariate model, two different parameterizations for the mean:
proc mixed data = growthgv method=ml;
class child group age;
model height = group age group*age / solution;
DATASET 1. GROWTH CURVES 3
repeated age / type=un subject=child r rcorr;
run;
proc mixed data = growthgv method=ml;
class child group age;
model height = group*age / noint solution;
repeated age / type=un subject=child r rcorr;
run;
2. Simplified mean structure:
data test;
set growthgv;
age = age-6;
ageclss = age;
run;
proc mixed data = test method=ml ;
class child group ageclss ;
model height = group group*age / solution noint;
repeated ageclss / type=un subject=child r rcorr;
run;
3. F -test for interaction:
proc mixed data = test method=ml;
class child group ageclss ;
model height = group group*age / solution noint;
repeated ageclss / type=un subject=child r rcorr;
contrast ’interactie’ group*age 1 -1 0, group*age 1 0 -1;
run;
proc mixed data = test method=ml;
class child group ageclss ;
model height = group age group*age / solution;
repeated ageclss / type=un subject=child r rcorr;
run;
Likelihood ratio test, using ML:
proc mixed data = test method=ml;
class child group ageclss ;
model height = group age / solution;
repeated ageclss / type=un subject=child r rcorr;
run;
4. Estimation of pairwise differences of average slopes:
proc mixed data = test method=ml;
class child group ageclss ;
model height = group group*age / solution noint;
repeated ageclss / type=un subject=child r rcorr;
estimate ’small-medium’ group*age 1 -1 0;
estimate ’small-tall’ group*age 1 0 -1;
estimate ’medium-tall’ group*age 0 1 -1;
run;
DATASET 1. GROWTH CURVES 4
5. Fitting the linear mixed model:
proc mixed data = test;
class child group;
model height = group group*age / noint solution;
random intercept age / type = un subject=child g;
run;
6. Comparison with model with unstructured covariance matrix:
proc mixed data = test ic;
class child group;
model height = group group*age / noint solution;
random intercept age / type = un subject=child g;
run;
proc mixed data = test ic;
class child group ageclss ;
model height = group group*age / solution noint;
repeated ageclss / type=un subject=child r rcorr;
run;
7. Robust inference:
proc mixed data = test empirical;
class child group;
model height = group group*age / noint solution;
random intercept age / type = un subject=child g;
run;
1.3.2 SAS Output
1. Full multivariate model, first parameterization for the mean:
Class Level Information
Class Levels Values
child 20 1 2 3 4 5 6 7 8 9 10 11 12 13
14 15 16 17 18 19 20
group 3 1 2 3
age 5 6 7 8 9 10
Iteration History
Iteration Evaluations -2 Log Like Criterion
0 1 494.40648596
1 1 239.97938687 0.00000000
Convergence criteria met.
DATASET 1. GROWTH CURVES 5
Estimated R Matrix for child 1
Row Col1 Col2 Col3 Col4 Col5
1 5.1910 5.8479 7.0247 6.3238 6.1008
2 5.8479 7.2479 8.3169 7.6600 7.3970
3 7.0247 8.3169 10.2337 9.3406 9.3120
4 6.3238 7.6600 9.3406 8.8596 8.9731
5 6.1008 7.3970 9.3120 8.9731 9.5521
Estimated R Correlation Matrix for child 1
Row Col1 Col2 Col3 Col4 Col5
1 1.0000 0.9534 0.9638 0.9325 0.8664
2 0.9534 1.0000 0.9657 0.9559 0.8890
3 0.9638 0.9657 1.0000 0.9810 0.9418
4 0.9325 0.9559 0.9810 1.0000 0.9754
5 0.8664 0.8890 0.9418 0.9754 1.0000
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) child 5.1910
UN(2,1) child 5.8479
UN(2,2) child 7.2479
UN(3,1) child 7.0247
UN(3,2) child 8.3169
UN(3,3) child 10.2337
UN(4,1) child 6.3238
UN(4,2) child 7.6600
UN(4,3) child 9.3406
UN(4,4) child 8.8596
UN(5,1) child 6.1008
UN(5,2) child 7.3970
UN(5,3) child 9.3120
UN(5,4) child 8.9731
UN(5,5) child 9.5521
Fit Statistics
-2 Log Likelihood 240.0
AIC (smaller is better) 300.0
AICC (smaller is better) 326.9
BIC (smaller is better) 329.9
Null Model Likelihood Ratio Test
DATASET 1. GROWTH CURVES 6
DF Chi-Square Pr > ChiSq
14 254.43 <.0001
Solution for Fixed Effects
Standard
Effect group age Estimate Error DF t Value Pr > |t|
Intercept 144.94 1.1682 17 124.08 <.0001
group 1 -11.2595 1.7195 17 -6.55 <.0001
group 2 -6.4857 1.6520 17 -3.93 0.0011
group 3 0 . . . .
age 6 -24.6286 0.6025 17 -40.87 <.0001
age 7 -18.2286 0.5353 17 -34.05 <.0001
age 8 -11.3000 0.4074 17 -27.74 <.0001
age 9 -5.0000 0.2579 17 -19.39 <.0001
age 10 0 . . . .
group*age 1 6 3.4786 0.8869 17 3.92 0.0011
group*age 1 7 2.8952 0.7880 17 3.67 0.0019
group*age 1 8 1.6000 0.5997 17 2.67 0.0162
group*age 1 9 0.06667 0.3796 17 0.18 0.8627
group*age 1 10 0 . . . .
group*age 2 6 2.4286 0.8521 17 2.85 0.0111
group*age 2 7 1.7000 0.7571 17 2.25 0.0383
group*age 2 8 0.5571 0.5762 17 0.97 0.3471
group*age 2 9 -0.2571 0.3647 17 -0.71 0.4903
group*age 2 10 0 . . . .
group*age 3 6 0 . . . .
group*age 3 7 0 . . . .
group*age 3 8 0 . . . .
group*age 3 9 0 . . . .
group*age 3 10 0 . . . .
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
group 2 17 19.81 <.0001
age 4 17 1263.53 <.0001
group*age 8 17 9.35 <.0001
2. Full multivariate model, second parameterization for the mean:
Estimated R Matrix for child 1
Row Col1 Col2 Col3 Col4 Col5
1 5.1910 5.8479 7.0247 6.3238 6.1008
DATASET 1. GROWTH CURVES 7
2 5.8479 7.2479 8.3169 7.6600 7.3970
3 7.0247 8.3169 10.2337 9.3406 9.3120
4 6.3238 7.6600 9.3406 8.8596 8.9731
5 6.1008 7.3970 9.3120 8.9731 9.5521
Estimated R Correlation Matrix for child 1
Row Col1 Col2 Col3 Col4 Col5
1 1.0000 0.9534 0.9638 0.9325 0.8664
2 0.9534 1.0000 0.9657 0.9559 0.8890
3 0.9638 0.9657 1.0000 0.9810 0.9418
4 0.9325 0.9559 0.9810 1.0000 0.9754
5 0.8664 0.8890 0.9418 0.9754 1.0000
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) child 5.1910
UN(2,1) child 5.8479
UN(2,2) child 7.2479
UN(3,1) child 7.0247
UN(3,2) child 8.3169
UN(3,3) child 10.2337
UN(4,1) child 6.3238
UN(4,2) child 7.6600
UN(4,3) child 9.3406
UN(4,4) child 8.8596
UN(5,1) child 6.1008
UN(5,2) child 7.3970
UN(5,3) child 9.3120
UN(5,4) child 8.9731
UN(5,5) child 9.5521
Fit Statistics
-2 Log Likelihood 240.0
AIC (smaller is better) 300.0
AICC (smaller is better) 326.9
BIC (smaller is better) 329.9
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
14 254.43 <.0001
Solution for Fixed Effects
DATASET 1. GROWTH CURVES 8
Standard
Effect group age Estimate Error DF t Value Pr > |t|
group*age 1 6 112.53 0.9301 20 120.99 <.0001
group*age 1 7 118.35 1.0991 20 107.68 <.0001
group*age 1 8 123.98 1.3060 20 94.93 <.0001
group*age 1 9 128.75 1.2152 20 105.95 <.0001
group*age 1 10 133.68 1.2618 20 105.95 <.0001
group*age 2 6 116.26 0.8611 20 135.00 <.0001
group*age 2 7 121.93 1.0176 20 119.83 <.0001
group*age 2 8 127.71 1.2091 20 105.63 <.0001
group*age 2 9 133.20 1.1250 20 118.40 <.0001
group*age 2 10 138.46 1.1682 20 118.53 <.0001
group*age 3 6 120.31 0.8611 20 139.71 <.0001
group*age 3 7 126.71 1.0176 20 124.53 <.0001
group*age 3 8 133.64 1.2091 20 110.53 <.0001
group*age 3 9 139.94 1.1250 20 124.39 <.0001
group*age 3 10 144.94 1.1682 20 124.08 <.0001
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
group*age 15 20 8511.09 <.0001
3. Model with simplified mean structure:
Estimated R Matrix for child 1
Row Col1 Col2 Col3 Col4 Col5
1 8.3335 9.2121 10.9714 9.7768 8.0299
2 9.2121 10.9370 12.6383 11.4137 9.6365
3 10.9714 12.6383 15.2964 13.7401 11.9267
4 9.7768 11.4137 13.7401 12.6910 11.2065
5 8.0299 9.6365 11.9267 11.2065 11.0842
Estimated R Correlation Matrix for child 1
Row Col1 Col2 Col3 Col4 Col5
1 1.0000 0.9649 0.9717 0.9507 0.8355
2 0.9649 1.0000 0.9771 0.9688 0.8752
3 0.9717 0.9771 1.0000 0.9862 0.9160
4 0.9507 0.9688 0.9862 1.0000 0.9449
5 0.8355 0.8752 0.9160 0.9449 1.0000
Covariance Parameter Estimates
DATASET 1. GROWTH CURVES 9
Cov Parm Subject Estimate
UN(1,1) child 8.3335
UN(2,1) child 9.2121
UN(2,2) child 10.9370
UN(3,1) child 10.9714
UN(3,2) child 12.6383
UN(3,3) child 15.2964
UN(4,1) child 9.7768
UN(4,2) child 11.4137
UN(4,3) child 13.7401
UN(4,4) child 12.6910
UN(5,1) child 8.0299
UN(5,2) child 9.6365
UN(5,3) child 11.9267
UN(5,4) child 11.2065
UN(5,5) child 11.0842
Fit Statistics
-2 Log Likelihood 275.4
AIC (smaller is better) 317.4
AICC (smaller is better) 329.2
BIC (smaller is better) 338.3
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
14 220.49 <.0001
Solution for Fixed Effects
Standard
Effect group Estimate Error DF t Value Pr > |t|
group 1 110.69 0.5916 17 187.09 <.0001
group 2 115.46 0.5477 17 210.79 <.0001
group 3 117.99 0.5477 17 215.41 <.0001
age*group 1 5.2503 0.1492 17 35.19 <.0001
age*group 2 5.6202 0.1381 17 40.69 <.0001
age*group 3 6.5309 0.1381 17 47.29 <.0001
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
group 3 17 41946.6 <.0001
DATASET 1. GROWTH CURVES 10
age*group 3 17 1710.16 <.0001
4. F -test for interaction, using CONTRAST statement:
Fit Statistics
-2 Log Likelihood 275.4
AIC (smaller is better) 317.4
AICC (smaller is better) 329.2
BIC (smaller is better) 338.3
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
14 220.49 <.0001
Solution for Fixed Effects
Standard
Effect group Estimate Error DF t Value Pr > |t|
group 1 110.69 0.5916 17 187.09 <.0001
group 2 115.46 0.5477 17 210.79 <.0001
group 3 117.99 0.5477 17 215.41 <.0001
age*group 1 5.2503 0.1492 17 35.19 <.0001
age*group 2 5.6202 0.1381 17 40.69 <.0001
age*group 3 6.5309 0.1381 17 47.29 <.0001
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
group 3 17 41946.6 <.0001
age*group 3 17 1710.16 <.0001
Contrasts
Num Den
Label DF DF F Value Pr > F
interactie 2 17 21.58 <.0001
5. F -test for interaction, using reparameterized mean structure:
Row Col1 Col2 Col3 Col4 Col5
1 8.3335 9.2121 10.9714 9.7768 8.0299
DATASET 1. GROWTH CURVES 11
2 9.2121 10.9370 12.6383 11.4137 9.6365
3 10.9714 12.6383 15.2964 13.7401 11.9267
4 9.7768 11.4137 13.7401 12.6910 11.2065
5 8.0299 9.6365 11.9267 11.2065 11.0842
Estimated R Correlation Matrix for child 1
Row Col1 Col2 Col3 Col4 Col5
1 1.0000 0.9649 0.9717 0.9507 0.8355
2 0.9649 1.0000 0.9771 0.9688 0.8752
3 0.9717 0.9771 1.0000 0.9862 0.9160
4 0.9507 0.9688 0.9862 1.0000 0.9449
5 0.8355 0.8752 0.9160 0.9449 1.0000
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) child 8.3335
UN(2,1) child 9.2121
UN(2,2) child 10.9370
UN(3,1) child 10.9714
UN(3,2) child 12.6383
UN(3,3) child 15.2964
UN(4,1) child 9.7768
UN(4,2) child 11.4137
UN(4,3) child 13.7401
UN(4,4) child 12.6910
UN(5,1) child 8.0299
UN(5,2) child 9.6365
UN(5,3) child 11.9267
UN(5,4) child 11.2065
UN(5,5) child 11.0842
Fit Statistics
-2 Log Likelihood 275.4
AIC (smaller is better) 317.4
AICC (smaller is better) 329.2
BIC (smaller is better) 338.3
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
14 220.49 <.0001
Solution for Fixed Effects
DATASET 1. GROWTH CURVES 12
Standard
Effect group Estimate Error DF t Value Pr > |t|
Intercept 117.99 0.5477 17 215.41 <.0001
group 1 -7.3019 0.8062 17 -9.06 <.0001
group 2 -2.5309 0.7746 17 -3.27 0.0045
group 3 0 . . . .
age 6.5309 0.1381 17 47.29 <.0001
age*group 1 -1.2806 0.2033 17 -6.30 <.0001
age*group 2 -0.9107 0.1953 17 -4.66 0.0002
age*group 3 0 . . . .
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
group 2 17 41.78 <.0001
age 1 17 5012.88 <.0001
age*group 2 17 21.58 <.0001
6. LR test for interaction:
Estimated R Matrix for child 1
Row Col1 Col2 Col3 Col4 Col5
1 10.7331 12.7128 15.8314 15.7841 14.5792
2 12.7128 15.7540 19.2380 19.4131 17.9419
3 15.8314 19.2380 24.3104 24.6143 23.0795
4 15.7841 19.4131 24.6143 25.7152 24.3106
5 14.5792 17.9419 23.0795 24.3106 23.5812
Estimated R Correlation Matrix for child 1
Row Col1 Col2 Col3 Col4 Col5
1 1.0000 0.9777 0.9801 0.9501 0.9164
2 0.9777 1.0000 0.9830 0.9645 0.9309
3 0.9801 0.9830 1.0000 0.9845 0.9639
4 0.9501 0.9645 0.9845 1.0000 0.9872
5 0.9164 0.9309 0.9639 0.9872 1.0000
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) child 10.7331
UN(2,1) child 12.7128
UN(2,2) child 15.7540
DATASET 1. GROWTH CURVES 13
UN(3,1) child 15.8314
UN(3,2) child 19.2380
UN(3,3) child 24.3104
UN(4,1) child 15.7841
UN(4,2) child 19.4131
UN(4,3) child 24.6143
UN(4,4) child 25.7152
UN(5,1) child 14.5792
UN(5,2) child 17.9419
UN(5,3) child 23.0795
UN(5,4) child 24.3106
UN(5,5) child 23.5812
Fit Statistics
-2 Log Likelihood 288.0
AIC (smaller is better) 326.0
AICC (smaller is better) 335.5
BIC (smaller is better) 345.0
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
14 211.76 <.0001
Solution for Fixed Effects
Standard
Effect group Estimate Error DF t Value Pr > |t|
Intercept 116.72 0.5385 17 216.74 <.0001
group 1 -5.7142 0.7658 17 -7.46 <.0001
group 2 -1.4018 0.7358 17 -1.91 0.0738
group 3 0 . . . .
age 5.5060 0.1121 17 49.11 <.0001
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
group 2 17 29.67 <.0001
age 1 17 2412.16 <.0001
7. Estimation of pairwise differences of average slopes:
Fit Statistics
-2 Log Likelihood 275.4
DATASET 1. GROWTH CURVES 14
AIC (smaller is better) 317.4
AICC (smaller is better) 329.2
BIC (smaller is better) 338.3
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
14 220.49 <.0001
Solution for Fixed Effects
Standard
Effect group Estimate Error DF t Value Pr > |t|
group 1 110.69 0.5916 17 187.09 <.0001
group 2 115.46 0.5477 17 210.79 <.0001
group 3 117.99 0.5477 17 215.41 <.0001
age*group 1 5.2503 0.1492 17 35.19 <.0001
age*group 2 5.6202 0.1381 17 40.69 <.0001
age*group 3 6.5309 0.1381 17 47.29 <.0001
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
group 3 17 41946.6 <.0001
age*group 3 17 1710.16 <.0001
Estimates
Standard
Label Estimate Error DF t Value Pr > |t|
small-medium -0.3699 0.2033 17 -1.82 0.0865
small-tall -1.2806 0.2033 17 -6.30 <.0001
medium-tall -0.9107 0.1953 17 -4.66 0.0002
8. Linear mixed model with random intercepts and slopes:
Estimated G Matrix
Row Effect child Col1 Col2
1 Intercept 1 7.0684 0.3546
2 age 1 0.3546 0.1331
Covariance Parameter Estimates
DATASET 1. GROWTH CURVES 15
Cov Parm Subject Estimate
UN(1,1) child 7.0684
UN(2,1) child 0.3546
UN(2,2) child 0.1331
Residual 0.4758
Fit Statistics
-2 Res Log Likelihood 315.7
AIC (smaller is better) 323.7
AICC (smaller is better) 324.2
BIC (smaller is better) 327.7
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
3 179.31 <.0001
Solution for Fixed Effects
Standard
Effect group Estimate Error DF t Value Pr > |t|
group 1 112.92 1.1071 60 102.00 <.0001
group 2 116.38 1.0250 60 113.54 <.0001
group 3 120.61 1.0250 60 117.68 <.0001
age*group 1 5.2700 0.1735 60 30.37 <.0001
age*group 2 5.5671 0.1606 60 34.66 <.0001
age*group 3 6.2486 0.1606 60 38.90 <.0001
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
group 3 60 12381.1 <.0001
age*group 3 60 1212.19 <.0001
9. Calculation of information criteria for random-effects model:
Fit Statistics
-2 Res Log Likelihood 315.7
AIC (smaller is better) 323.7
AICC (smaller is better) 324.2
BIC (smaller is better) 327.7
DATASET 1. GROWTH CURVES 16
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
3 179.31 <.0001
Information Criteria
Neg2LogLike Parms AIC AICC HQIC BIC CAIC
315.7 4 323.7 324.2 324.5 327.7 331.7
10. Calculation of information criteria for model with unstructured covariance matrix:
Fit Statistics
-2 Res Log Likelihood 279.4
AIC (smaller is better) 309.4
AICC (smaller is better) 315.5
BIC (smaller is better) 324.3
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
14 215.67 <.0001
Information Criteria
Neg2LogLike Parms AIC AICC HQIC BIC CAIC
279.4 15 309.4 315.5 312.3 324.3 339.3
11. Robust inference:
Estimated G Matrix
Row Effect child Col1 Col2
1 Intercept 1 7.0684 0.3546
2 age 1 0.3546 0.1331
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) child 7.0684
UN(2,1) child 0.3546
UN(2,2) child 0.1331
DATASET 1. GROWTH CURVES 17
Residual 0.4758
Fit Statistics
-2 Res Log Likelihood 315.7
AIC (smaller is better) 323.7
AICC (smaller is better) 324.2
BIC (smaller is better) 327.7
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
3 179.31 <.0001
Solution for Fixed Effects
Standard
Effect group Estimate Error DF t Value Pr > |t|
group 1 112.92 0.7545 60 149.66 <.0001
group 2 116.38 0.9886 60 117.72 <.0001
group 3 120.61 1.0751 60 112.19 <.0001
age*group 1 5.2700 0.1337 60 39.40 <.0001
age*group 2 5.5671 0.1059 60 52.55 <.0001
age*group 3 6.2486 0.1957 60 31.93 <.0001
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
group 3 60 16280.8 <.0001
age*group 3 60 1777.78 <.0001
1.3.3 Discussion
1. Two different parameterizations of the full multivariate model: As is to be expected, the samemaximized likelihood value is obtained, as well as the same marginal covariance matrix. Under the firstparameterization, the parameters represent contrasts between specific group means. Under the first param-eterization, the parameters represent average response values at each combination of group with age.
2. Simplified mean structure: The value 6 is first subtracted from the variable age, such that intercepts canbe interpreted as averages at the start of the study, rather than averages at the age of 0 years. In order toimmediately obtain estimates for the three intercepts as well as three slopes (rather than contrasts betweenthose parameters), the mean is parameterized as group group*age.
3. F -test for interaction: The F -test can be obtained under the original parameterization, using a CON-TRAST statement, but also as a default F -test under the parameterization group age group*age.
DATASET 1. GROWTH CURVES 18
4. LR test: Since the models we are comparing have different mean structures, a valid LR test can only beobtained under ML estimation. The difference in minus twice the maximized log-likelihood value equals288.0493− 275.3983 = 12.651 which is significant when compared to a chi-squared distribution with twodegrees of freedom (p = 0.00179).
5. Pairwise comparisons of slopes: There is no significant difference in average trend between the childrenwith small mothers and children with medium mothers (p = 0.0865), but the children with tall mothersgrow significantly faster than those with small mothers or those with medium mothers (p < 0.0001, andp = 0.0002, respectively).
6. Comparison with random-effects model:
• Using LR test: Since both models have the same mean structure, a valid LR test can be obtained,even under REML estimation. The difference in minus twice the maximized REML log-likelihood valueequals 315.7478−279.3868 = 36.361 which is significant when compared to a chi-squared distributionwith 11 degrees of freedom (p = 0.000147).
• Using Information Criteria: AIC and HQIC prefer the unstructured model, while BIC and CAICprefer the random-effects model. This illustrates the informal, exploratory, nature of the informationcriteria.
The LR test clearly suggests that the random-effects covariance matrix is not appropriate. This impliesthat inferences, under the random-effects model, for the fixed effects need correction for this, hence robustinference is required.
7. Robust inference: Note that the same maximized likelihood values are obtained, as well as the sameparameter estimates. The only difference is in the standard errors for the fixed effects. Some robust s.e.’sare smaller, others are larger than the original naive s.e.’s.
Dataset 2
Growth Data
2.1 The Data
These data, introduced by Potthof and Roy (1964), contain growth measurements for 11 girls and 16 boys. Foreach subject the distance from the center of the pituitary to the maxillary fissure was recorded at the ages 8,10, 12, and 14. The data were used by Jennrich and Schluchter (1986) to illustrate estimation methods forunbalanced data, where unbalancedness is now to be interpreted in the sense of an unequal number of boys andgirls.
Little and Rubin (1987) deleted 9 of the [(11 +16)× 4] measurements, rendering 9 incomplete subjects. Deletionis confined to the age 10 measurements. Little and Rubin (1987) describe the mechanism to be such that subjectswith a low value at age 8 are more likely to have a missing value at age 10.
These data are analyzed at length in Verbeke and Molenberghs (1997; Ch. 4.4 and throughout Ch. 5) and inVerbeke and Molenberghs (2000, Ch. 17). We refer to these texts for tabular and graphical representations ofthe data.
2.2 Questions
Consider the complete cases (GROWTHCC.SAS7BDAT). In particular, we focus on Model 6:
• separate linear profiles for boys and girls,
• random intercept and random slope with general 2 × 2 covariance matrix D.
Fit this model under the following 2 × 2 “factorial design”:
• untransformed age (representing time as well) versus
age2 =age− 11
3,
• with and without the ‘nobound’ option.
19
DATASET 2. GROWTH DATA 20
Upon fitting these models, formulate an answer to the following questions:
• In which statement is the ‘nobound’ option to be placed ?
• What is the use of the ‘nobound’ option ?
• Study the LOG screen of SAS with care.
• Study the covariance matrices of the random effects in all four models.
• Calculate the covariance matrix of the 4 repeated measures and discuss.
• Do the different models (substantially) alter the estimates of the mean response profiles ?
In addition, starting from Model 7, formulate two additional models, with the same fixed-effects structure andthe following variance-covariance structures:
• Model 9: random intercept and AR(1) serial structure;
• Model 10: random intercept, AR(1) serial structure, and measurement error.
(Note: the answer to this last question can be found in Verbeke and Molenberghs (1997, p. 261).)
The relevant variables in GROWTHCC.SAS7BDAT are:
MEASURE: response variable, growth measurement;
SEX: 1 for boys, 2 for girls;
AGE: age in years (8, 10, 12, 14).
2.3 Elements of Solution
2.3.1 Programs
libname m ’\bartsas\gent’;
proc mixed data=m.growthcc method=ml;
title ’Growth Data (Complete Cases), Model 6’;
title2 ’Untransformed age’;
class sex idnr;
model measure=sex age*sex / s;
random intercept age / type=un subject=idnr g v vcorr;
run;
proc mixed data=m.growthcc method=ml;
title ’Growth Data (Complete Cases), Model 6’;
title2 ’Untransformed age - Nobound’;
class sex idnr;
model measure=sex age*sex / s;
parms / nobound;
DATASET 2. GROWTH DATA 21
random intercept age / type=un subject=idnr g v vcorr;
run;
data hulp;
set m.growthcc;
age2=age-11;
age2=age2/3;
run;
proc mixed data=hulp method=ml;
title ’Growth Data (Complete Cases), Model 6’;
title2 ’Transformed age: (age-11)/3’;
class sex idnr;
model measure=sex age2*sex / s;
random intercept age2 / type=un subject=idnr g v vcorr;
run;
proc mixed data=hulp method=ml;
title ’Growth Data (Complete Cases), Model 6’;
title2 ’Transformed age: (age-11)/3 - Nobound’;
class sex idnr;
model measure=sex age2*sex / s;
parms / nobound;
random intercept age2 / type=un subject=idnr g v vcorr;
run;
These programs include the options ‘g’, ‘v’, and ‘vcorr’ in the RANDOM statement. They produce the covariancematrix of the random effects (D in the notes), and the total variance-covariance matrix together with the derivedcorrelation matrix, respectively:
V = ZDZ′ +D = ZDZ′ +G.
Indeed, the design matrix for the random effects is common to all subjects:
Z =
1 8
1 10
1 12
1 14
.
2.3.2 SAS Output
Growth Data (Complete Cases), Model 6 11
Untransformed age 15:29 Monday, April 24, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
SEX 2 1 2
IDNR 18 1 2 4 5 7 8 11 12 14 15 17 18
19 20 21 22 25 26
DATASET 2. GROWTH DATA 22
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 173.83597294
1 2 217.95942441 0.31464225
2 1 207.78119685 1.02096475
3 1 197.51841663 3.35649391
4 1 187.22267468 11.09067497
5 1 176.90118943 36.62110390
6 1 166.51223080 118.41214091
7 1 155.90700618 275.34606092
8 3 152.48908720 35.92986685
9 1 151.30481194 16.48576496
10 2 147.72234368 292.28142431
11 2 146.11148938 0.45023154
12 3 144.78806054 .
13 3 144.61828469 .
14 1 144.51081783 0.00004756
15 1 144.50729532 0.00000007
16 1 144.50729017 0.00000000
Convergence criteria met.
G Matrix
Effect IDNR Row COL1 COL2
INTERCEPT 1 1 -0.00000000 0.11027204
AGE 1 2 0.11027204 0.00000000
V Matrix for IDNR 1
Row COL1 COL2 COL3 COL4
1 3.49309330 1.98489673 2.20544081 2.42598489
2 1.98489673 3.93418146 2.42598489 2.64652897
3 2.20544081 2.42598489 4.37526962 2.86707306
4 2.42598489 2.64652897 2.86707306 4.81635778
Growth Data (Complete Cases), Model 6 12
Untransformed age 15:29 Monday, April 24, 2000
V Correlation Matrix for IDNR 1
Row COL1 COL2 COL3 COL4
1 1.00000000 0.53543361 0.56414131 0.59145762
2 0.53543361 1.00000000 0.58473419 0.60798111
3 0.56414131 0.58473419 1.00000000 0.62456404
4 0.59145762 0.60798111 0.62456404 1.00000000
Covariance Parameter Estimates (MLE)
DATASET 2. GROWTH DATA 23
Cov Parm Subject Estimate
UN(1,1) IDNR -0.00000000
UN(2,1) IDNR 0.11027204
UN(2,2) IDNR 0.00000000
Residual 1.72874065
Model Fitting Information for MEASURE
Description Value
Observations 72.0000
Log Likelihood -138.417
Akaike’s Information Criterion -142.417
Schwarz’s Bayesian Criterion -146.971
-2 Log Likelihood 276.8344
Null Model LRT Chi-Square 29.3287
Null Model LRT DF 3.0000
Null Model LRT P-Value 0.0000
Solution for Fixed Effects
Effect SEX Estimate Std Error DF t Pr > |t|
INTERCEPT 18.29285714 1.24734381 16 14.67 0.0001
SEX 1 -0.11558442 1.59560756 36 -0.07 0.9427
SEX 2 0.00000000 . . . .
AGE*SEX 1 0.67500000 0.08864486 36 7.61 0.0001
AGE*SEX 2 0.47500000 0.11112222 36 4.27 0.0001
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
SEX 1 36 0.01 0.9427
AGE*SEX 2 36 38.13 0.0001
Growth Data (Complete Cases), Model 6 13
Untransformed age - Nobound 15:29 Monday, April 24, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
SEX 2 1 2
IDNR 18 1 2 4 5 7 8 11 12 14 15 17 18
19 20 21 22 25 26
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
DATASET 2. GROWTH DATA 24
0 1 173.83597294
1 1 143.34782275 0.00000000
Convergence criteria met.
G Matrix
Effect IDNR Row COL1 COL2
INTERCEPT 1 1 -4.40880772 0.49152778
AGE 1 2 0.49152778 -0.03388889
V Matrix for IDNR 1
Row COL1 COL2 COL3 COL4
1 3.26591450 1.72758117 2.16841450 2.60924784
2 1.72758117 4.01202561 2.33813672 2.64341450
3 2.16841450 2.33813672 4.48702561 2.67758117
4 2.60924784 2.64341450 2.67758117 4.69091450
V Correlation Matrix for IDNR 1
Row COL1 COL2 COL3 COL4
1 1.00000000 0.47725909 0.56644875 0.66662895
2 0.47725909 1.00000000 0.55107255 0.60933295
3 0.56644875 0.55107255 1.00000000 0.58362597
4 0.66662895 0.60933295 0.58362597 1.00000000
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate
UN(1,1) IDNR -4.40880772
Growth Data (Complete Cases), Model 6 14
Untransformed age - Nobound 15:29 Monday, April 24, 2000
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate
UN(2,1) IDNR 0.49152778
UN(2,2) IDNR -0.03388889
Residual 1.97916667
Model Fitting Information for MEASURE
Description Value
Observations 72.0000
DATASET 2. GROWTH DATA 25
Log Likelihood -137.837
Akaike’s Information Criterion -141.837
Schwarz’s Bayesian Criterion -146.391
-2 Log Likelihood 275.6750
PARMS Model LRT Chi-Square 30.4882
PARMS Model LRT DF 3.0000
PARMS Model LRT P-Value 0.0000
Solution for Fixed Effects
Effect SEX Estimate Std Error DF t Pr > |t|
INTERCEPT 18.29285714 1.07304256 16 17.05 0.0001
SEX 1 -0.11558442 1.37264065 36 -0.08 0.9334
SEX 2 0.00000000 . . . .
AGE*SEX 1 0.67500000 0.07691166 36 8.78 0.0001
AGE*SEX 2 0.47500000 0.09641387 36 4.93 0.0001
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
SEX 1 36 0.01 0.9334
AGE*SEX 2 36 50.65 0.0001
Growth Data (Complete Cases), Model 6 15
Transformed age: (age-11)/3 15:29 Monday, April 24, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
SEX 2 1 2
IDNR 18 1 2 4 5 7 8 11 12 14 15 17 18
19 20 21 22 25 26
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 173.83597294
1 4 144.51319717 0.00239701
2 1 144.35391719 0.00006774
3 1 144.34888414 0.00000014
4 1 144.34887385 0.00000000
Convergence criteria met.
G Matrix
Effect IDNR Row COL1 COL2
DATASET 2. GROWTH DATA 26
INTERCEPT 1 1 2.43597060 0.47994377
AGE2 1 2 0.47994377 0.00000000
V Matrix for IDNR 1
Row COL1 COL2 COL3 COL4
1 3.22932491 1.79604558 2.11600809 2.43597060
2 1.79604558 3.86924994 2.43597060 2.75593312
3 2.11600809 2.43597060 4.50917496 3.07589563
4 2.43597060 2.75593312 3.07589563 5.14909999
V Correlation Matrix for IDNR 1
Row COL1 COL2 COL3 COL4
1 1.00000000 0.50809871 0.55451450 0.59737977
2 0.50809871 1.00000000 0.58319005 0.61743269
3 0.55451450 0.58319005 1.00000000 0.63834783
4 0.59737977 0.61743269 0.63834783 1.00000000
Growth Data (Complete Cases), Model 6 16
Transformed age: (age-11)/3 15:29 Monday, April 24, 2000
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate
UN(1,1) IDNR 2.43597060
UN(2,1) IDNR 0.47994377
UN(2,2) IDNR -0.00000000
Residual 1.75324185
Model Fitting Information for MEASURE
Description Value
Observations 72.0000
Log Likelihood -138.338
Akaike’s Information Criterion -142.338
Schwarz’s Bayesian Criterion -146.891
-2 Log Likelihood 276.6760
Null Model LRT Chi-Square 29.4871
Null Model LRT DF 3.0000
Null Model LRT P-Value 0.0000
Solution for Fixed Effects
Effect SEX Estimate Std Error DF t Pr > |t|
INTERCEPT 23.51785714 0.64078981 16 36.70 0.0001
SEX 1 2.08441558 0.81970108 36 2.54 0.0154
SEX 2 0.00000000 . . . .
AGE2*SEX 1 2.02500000 0.26781249 36 7.56 0.0001
DATASET 2. GROWTH DATA 27
AGE2*SEX 2 1.42500000 0.33572072 36 4.24 0.0001
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
SEX 1 36 6.47 0.0154
AGE2*SEX 2 36 37.59 0.0001
Growth Data (Complete Cases), Model 6 17
Transformed age: (age-11)/3 - Nobound
15:29 Monday, April 24, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
SEX 2 1 2
IDNR 18 1 2 4 5 7 8 11 12 14 15 17 18
19 20 21 22 25 26
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 173.83597294
1 1 143.34782275 0.00000000
Convergence criteria met.
G Matrix
Effect IDNR Row COL1 COL2
INTERCEPT 1 1 2.30424784 0.35625000
AGE2 1 2 0.35625000 -0.30500000
V Matrix for IDNR 1
Row COL1 COL2 COL3 COL4
1 3.26591450 1.72758117 2.16841450 2.60924784
2 1.72758117 4.01202561 2.33813672 2.64341450
3 2.16841450 2.33813672 4.48702561 2.67758117
4 2.60924784 2.64341450 2.67758117 4.69091450
V Correlation Matrix for IDNR 1
Row COL1 COL2 COL3 COL4
1 1.00000000 0.47725909 0.56644875 0.66662895
DATASET 2. GROWTH DATA 28
2 0.47725909 1.00000000 0.55107255 0.60933295
3 0.56644875 0.55107255 1.00000000 0.58362597
4 0.66662895 0.60933295 0.58362597 1.00000000
Growth Data (Complete Cases), Model 6 18
Transformed age: (age-11)/3 - Nobound
15:29 Monday, April 24, 2000
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate
UN(1,1) IDNR 2.30424784
UN(2,1) IDNR 0.35625000
UN(2,2) IDNR -0.30500000
Residual 1.97916667
Model Fitting Information for MEASURE
Description Value
Observations 72.0000
Log Likelihood -137.837
Akaike’s Information Criterion -141.837
Schwarz’s Bayesian Criterion -146.391
-2 Log Likelihood 275.6750
PARMS Model LRT Chi-Square 30.4882
PARMS Model LRT DF 3.0000
PARMS Model LRT P-Value 0.0000
Solution for Fixed Effects
Effect SEX Estimate Std Error DF t Pr > |t|
INTERCEPT 23.51785714 0.63234705 16 37.19 0.0001
SEX 1 2.08441558 0.80890106 36 2.58 0.0142
SEX 2 0.00000000 . . . .
AGE2*SEX 1 2.02500000 0.23073499 36 8.78 0.0001
AGE2*SEX 2 1.42500000 0.28924162 36 4.93 0.0001
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
SEX 1 36 6.64 0.0142
AGE2*SEX 2 36 50.65 0.0001
2.3.3 Discussion
Note that the omission of ‘nobound’ forces the G matrix to have nonnegative diagonal elements. However, evenin that case the G matrix is non-positive definite ! Hence, this solution makes little sense. This non-PSD propertyis listed in the LOG screen of SAS.
DATASET 2. GROWTH DATA 29
However, the resulting V matrix is positive definite in all cases and hence a valid covariance structure is obtained.
Both models with ‘nobound’ produce the same V matrix, which is different from the other two. The modelswithout ‘nobound’ have a different V matrix: they ‘hit’ the boundary of the parameter space considered at adifferent location.
Finally, there is no impact on the fixed effects.
Dataset 3
Mastitis in Dairy Cattle
3.1 The Data
This example, concerning the occurrence of the infectious disease mastitis in dairy cows, was introduced in Diggleand Kenward (1994) and reanalyzed in Kenward (1998). Data were available of the milk yields in thousands ofliters of 107 dairy cows from a single herd in 2 consecutive years: Yij (i = 1, . . . , 107; j = 1, 2). In the first year,all animals were supposedly free of mastitis; in the second year, 27 became infected. Mastitis typically reducesmilk yield, and the question of scientific interest is whether the probability of occurrence of mastitis is related tothe yield that would have been observed had mastitis not occurred. A graphical representation of the completedata is given in Figure 3.1.
The data are analyzed at length in Verbeke and Molenberghs (2000).
Figure 3.1: Mastitis in Dairy Cattle. The first panel shows a scatter plot of the second measurement versus
the first measurement. The second panel shows a scatter plot of the change versus the baseline measurement.
30
DATASET 3. MASTITIS IN DAIRY CATTLE 31
3.2 Questions
3.2.1 Missing Data Analysis
Construct an unstructured bivariate model for these data, under a variety of missing data assumptions:
• complete case analysis
• last observation carried forward
• unconditional mean imputation
• conditional mean imputation
• likelihood-based available case analysis
Is it possible to code the models such that both variances are produced, together with the correlation ?
3.2.2 Intraclass Correlation
Calculate the intraclass correlation, under the assumptions of heterogeneous and homogeneous variance.
3.3 Elements of Solution
3.3.1 Data Manipulation
The following GAUSS code was used to construct the datasets:
data1="\\bartsas\\gent\\mast01";
open handle=^data1 for read;
mast01=readr(handle,1000);
close(handle);
ind=mast01[.,1];
tijd=mast01[.,2];
resp=mast01[.,3];
n=rows(resp)/2;
resp=ind[seqa(1,2,n)]~reshape(resp,n,2);
respcc=packr(resp);
resplocf=resp;
test=missrv(resplocf[.,3],10000);
resplocf[.,3]=(test.*(test./=10000))+(resplocf[.,2].*(test.==10000));
DATASET 3. MASTITIS IN DAIRY CATTLE 32
hulp=meanc(respcc[.,3]);
respmean=resp;
respmean[.,3]=missrv(respmean[.,3],hulp);
respcond=resp;
hulp=6.4435+0.6479*inv(0.9115)*(resp[.,2]-6.4435+0.7359);
respcond[.,3]=(test.*(test./=10000))+(hulp.*(test.==10000));
h1=(respcc[.,1].*.ones(2,1));
h2=ones(80,1).*.(0|1);
h3=vec(respcc[.,2 3]’);
let naam=ident ti yy;
dataset="\\bartsas\\gent\\mastcc";
create handle=^dataset with ^naam,0,4;
writer(handle,h1~h2~h3);
close(handle);
h1=(resplocf[.,1].*.ones(2,1));
h2=ones(107,1).*.(0|1);
h3=vec(resplocf[.,2 3]’);
let naam=ident ti yy;
dataset="\\bartsas\\gent\\mastlocf";
create handle=^dataset with ^naam,0,4;
writer(handle,h1~h2~h3);
close(handle);
h1=(respmean[.,1].*.ones(2,1));
h2=ones(107,1).*.(0|1);
h3=vec(respmean[.,2 3]’);
let naam=ident ti yy;
dataset="\\bartsas\\gent\\mastmean";
create handle=^dataset with ^naam,0,4;
writer(handle,h1~h2~h3);
close(handle);
h1=(respcond[.,1].*.ones(2,1));
h2=ones(107,1).*.(0|1);
h3=vec(respcond[.,2 3]’);
let naam=ident ti yy;
dataset="\\bartsas\\gent\\mastcond";
create handle=^dataset with ^naam,0,4;
writer(handle,h1~h2~h3);
close(handle);
3.3.2 Datasets
MAST01.SAS7BDAT: Original data.
MASTCC.SAS7BDAT: Complete cases only.
MASTLOCF.SAS7BDAT: Last observation carried forward.
DATASET 3. MASTITIS IN DAIRY CATTLE 33
MASTMEAN.SAS7BDAT: Unconditional mean imputation.
MASTCOND.SAS7BDAT: Conditional mean imputation.
3.3.3 Model Formulation
SAS Code
libname m ’c:\bartsas\gent’;
proc mixed data=m.mastcc method=ml covtest;
title ’Complete Case Analysis’;
class ti;
model yy=ti / s;
repeated ti / type=csh subject=ident r;
run;
proc mixed data=m.mastcc method=ml covtest;
title ’Complete Case Analysis - Random Effects Version’;
class ti;
model yy=ti / s;
repeated ti / type=un(1) subject=ident r;
random intercept / subject=ident v;
id ident ti;
run;
proc mixed data=m.mastlocf method=ml covtest;
title ’Last Observation Carried Forward’;
class ti;
model yy=ti / s;
repeated ti / type=csh subject=ident r;
run;
proc mixed data=m.mastmean method=ml covtest;
title ’Unconditional Mean Imputation’;
class ti;
model yy=ti / s;
repeated ti / type=csh subject=ident r;
run;
proc mixed data=m.mastcond method=ml covtest;
title ’Conditional Mean Imputation’;
class ti;
model yy=ti / s;
repeated ti / type=csh subject=ident r;
run;
proc mixed data=m.mast01 method=ml covtest;
title ’Available Case/Ignorable Analysis’;
class ti;
model yy=ti / s;
repeated ti / type=csh subject=ident r;
DATASET 3. MASTITIS IN DAIRY CATTLE 34
run;
SAS Output
Complete Case Analysis 12:17 Sunday, April 23, 2000 523
The MIXED Procedure
Class Level Information
Class Levels Values
TI 2 0 1
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 177.40559384
1 1 140.31178413 0.00000000
Convergence criteria met.
R Matrix for Subject 1
Row COL1 COL2
1 0.91148521 0.64793800
2 0.64793800 1.31835993
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
Var(1) IDENT 0.91148521 0.14411847 6.32 0.0001
Var(2) IDENT 1.31835993 0.20845101 6.32 0.0001
CSH IDENT 0.59107371 0.07274285 8.13 0.0001
Model Fitting Information for YY
Description Value
Observations 160.0000
Log Likelihood -217.186
Akaike’s Information Criterion -220.186
Schwarz’s Bayesian Criterion -224.799
-2 Log Likelihood 434.3721
Null Model LRT Chi-Square 37.0938
Null Model LRT DF 2.0000
Null Model LRT P-Value 0.0000
DATASET 3. MASTITIS IN DAIRY CATTLE 35
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
INTERCEPT 6.44348574 0.12837250 79 50.19 0.0001
Complete Case Analysis 12:17 Sunday, April 23, 2000 524
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
TI 0 -0.73588719 0.10804913 79 -6.81 0.0001
TI 1 0.00000000 . . . .
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TI 1 79 46.39 0.0001
Complete Case Analysis - Random Effects Version 525
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TI 2 0 1
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 177.40559384
1 1 140.31178413 0.00000000
Convergence criteria met.
R Matrix for Subject 1
Row COL1 COL2
1 0.26354721
2 0.67042193
V Matrix for Subject 1
Row COL1 COL2
1 0.91148521 0.64793800
DATASET 3. MASTITIS IN DAIRY CATTLE 36
2 0.64793800 1.31835993
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
INTERCEPT IDENT 0.64793800 0.14236789 4.55 0.0001
UN(1,1) IDENT 0.26354721 0.10728212 2.46 0.0140
UN(2,1) IDENT 0.00000000 . . .
UN(2,2) IDENT 0.67042193 0.14494710 4.63 0.0001
Model Fitting Information for YY
Description Value
Observations 160.0000
Log Likelihood -217.186
Akaike’s Information Criterion -220.186
Schwarz’s Bayesian Criterion -224.799
-2 Log Likelihood 434.3721
Complete Case Analysis - Random Effects Version 526
12:17 Sunday, April 23, 2000
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
INTERCEPT 6.44348574 0.12837250 79 50.19 0.0001
TI 0 -0.73588719 0.10804913 79 -6.81 0.0001
TI 1 0.00000000 . . . .
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TI 1 79 46.39 0.0001
Last Observation Carried Forward 527
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TI 2 0 1
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
DATASET 3. MASTITIS IN DAIRY CATTLE 37
0 1 222.10149267
1 1 166.53560980 0.00000000
Convergence criteria met.
R Matrix for Subject 1
Row COL1 COL2
1 0.86701950 0.63835255
2 0.63835255 1.21014683
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
Var(1) IDENT 0.86701950 0.11853647 7.31 0.0001
Var(2) IDENT 1.21014683 0.16544787 7.31 0.0001
CSH IDENT 0.62319955 0.05912776 10.54 0.0001
Model Fitting Information for YY
Description Value
Observations 214.0000
Log Likelihood -279.921
Akaike’s Information Criterion -282.921
Schwarz’s Bayesian Criterion -287.970
-2 Log Likelihood 559.8413
Null Model LRT Chi-Square 55.5659
Null Model LRT DF 2.0000
Null Model LRT P-Value 0.0000
Last Observation Carried Forward 528
12:17 Sunday, April 23, 2000
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
INTERCEPT 6.31526919 0.10634747 106 59.38 0.0001
TI 0 -0.55019603 0.08649246 106 -6.36 0.0001
TI 1 0.00000000 . . . .
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TI 1 106 40.46 0.0001
Unconditional Mean Imputation 529
12:17 Sunday, April 23, 2000
DATASET 3. MASTITIS IN DAIRY CATTLE 38
The MIXED Procedure
Class Level Information
Class Levels Values
TI 2 0 1
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 197.62938561
1 1 162.83816167 0.00000000
Convergence criteria met.
R Matrix for Subject 1
Row COL1 COL2
1 0.86701950 0.48443961
2 0.48443961 0.98568967
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
Var(1) IDENT 0.86701950 0.11853647 7.31 0.0001
Var(2) IDENT 0.98568967 0.13476072 7.31 0.0001
CSH IDENT 0.52402875 0.07012647 7.47 0.0001
Model Fitting Information for YY
Description Value
Observations 214.0000
Log Likelihood -278.072
Akaike’s Information Criterion -281.072
Schwarz’s Bayesian Criterion -286.121
-2 Log Likelihood 556.1439
Null Model LRT Chi-Square 34.7912
Null Model LRT DF 2.0000
Null Model LRT P-Value 0.0000
Unconditional Mean Imputation 530
12:17 Sunday, April 23, 2000
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
INTERCEPT 6.44348562 0.09597944 106 67.13 0.0001
TI 0 -0.67841246 0.09088505 106 -7.46 0.0001
DATASET 3. MASTITIS IN DAIRY CATTLE 39
TI 1 0.00000000 . . . .
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TI 1 106 55.72 0.0001
Conditional Mean Imputation 531
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TI 2 0 1
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 208.19212620
1 1 151.19968795 0.00000000
Convergence criteria met.
R Matrix for Subject 1
Row COL1 COL2
1 0.86701950 0.61631974
2 0.61631974 1.07943125
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
Var(1) IDENT 0.86701950 0.11853647 7.31 0.0001
Var(2) IDENT 1.07943125 0.14757680 7.31 0.0001
CSH IDENT 0.63708027 0.05743659 11.09 0.0001
Model Fitting Information for YY
Description Value
Observations 214.0000
Log Likelihood -272.253
Akaike’s Information Criterion -275.253
Schwarz’s Bayesian Criterion -280.302
-2 Log Likelihood 544.5054
Null Model LRT Chi-Square 56.9924
DATASET 3. MASTITIS IN DAIRY CATTLE 40
Null Model LRT DF 2.0000
Null Model LRT P-Value 0.0000
Conditional Mean Imputation 532
12:17 Sunday, April 23, 2000
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
INTERCEPT 6.48434231 0.10043975 106 64.56 0.0001
TI 0 -0.71926916 0.08167701 106 -8.81 0.0001
TI 1 0.00000000 . . . .
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TI 1 106 77.55 0.0001
Available Case/Ignorable Analysis 533
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TI 2 0 1
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 197.91504041
1 2 159.45922194 0.00001599
2 1 159.45793872 0.00000000
Convergence criteria met.
R Matrix for Subject 1
Row COL1 COL2
1 0.86702230 0.61635644
2 0.61635644 1.29589716
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
Var(1) IDENT 0.86702230 0.11853604 7.31 0.0001
DATASET 3. MASTITIS IN DAIRY CATTLE 41
Var(2) IDENT 1.29589716 0.19963832 6.49 0.0001
CSH IDENT 0.58147565 0.07117100 8.17 0.0001
Model Fitting Information for YY
Description Value
Observations 187.0000
Log Likelihood -251.570
Akaike’s Information Criterion -254.570
Schwarz’s Bayesian Criterion -259.417
-2 Log Likelihood 503.1410
Null Model LRT Chi-Square 38.4571
Null Model LRT DF 2.0000
Null Model LRT P-Value 0.0000
Available Case/Ignorable Analysis 534
12:17 Sunday, April 23, 2000
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
INTERCEPT 6.48434379 0.12172372 106 53.27 0.0001
TI 0 -0.71927064 0.10676608 79 -6.74 0.0001
TI 1 0.00000000 . . . .
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TI 1 79 45.39 0.0001
3.3.4 Intraclass Correlation
The programs considered sofar employed heterogeneous compound symmetry models which, in the case of twooutcomes, produce two variances, one for each time point, and a correlation coefficient. While not entirelyconsistent with the definition of intraclass correlation, it is a relevant concept in this case since there is a naturalordering of the measurements within a cow.
In case variances are equal (which they are in this case, as can be verified from, for example, likelihood ratiotests), then a common variance can be considered using a number of equivalent models such as:
• compound symmetry,
• random intercepts,
• AR(1) (this equivalence holds only in the case of two outcomes).
The advantage of the latter model is that it explicitly produces a correlation coefficient. For the other models,the correlation has to be calculated from the variance parameters.
DATASET 3. MASTITIS IN DAIRY CATTLE 42
Program
libname m ’c:\bartsas\gent’;
proc mixed data=m.mastcc method=ml covtest;
title ’Complete Case Analysis’;
class ti;
model yy=ti / s;
repeated ti / type=ar(1) subject=ident r;
run;
proc mixed data=m.mastlocf method=ml covtest;
title ’Last Observation Carried Forward’;
class ti;
model yy=ti / s;
repeated ti / type=ar(1) subject=ident r;
run;
proc mixed data=m.mastmean method=ml covtest;
title ’Unconditional Mean Imputation’;
class ti;
model yy=ti / s;
repeated ti / type=ar(1) subject=ident r;
run;
proc mixed data=m.mastcond method=ml covtest;
title ’Conditional Mean Imputation’;
class ti;
model yy=ti / s;
repeated ti / type=ar(1) subject=ident r;
run;
proc mixed data=m.mast01 method=ml covtest;
title ’Available Case/Ignorable Analysis’;
class ti;
model yy=ti / s;
repeated ti / type=ar(1) subject=ident r;
run;
SAS Output
Complete Case Analysis 12:17 Sunday, April 23, 2000 545
The MIXED Procedure
Class Level Information
Class Levels Values
TI 2 0 1
DATASET 3. MASTITIS IN DAIRY CATTLE 43
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 177.40559384
1 1 144.43830022 0.00000000
Convergence criteria met.
R Matrix for Subject 1
Row COL1 COL2
1 1.11492257 0.64793800
2 0.64793800 1.11492257
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
AR(1) IDENT 0.58115067 0.07404335 7.85 0.0001
Residual 1.11492257 0.14417333 7.73 0.0001
Model Fitting Information for YY
Description Value
Observations 160.0000
Log Likelihood -219.249
Akaike’s Information Criterion -221.249
Schwarz’s Bayesian Criterion -224.324
-2 Log Likelihood 438.4986
Null Model LRT Chi-Square 32.9673
Null Model LRT DF 1.0000
Null Model LRT P-Value 0.0000
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
INTERCEPT 6.44348574 0.11805309 79 54.58 0.0001
TI 0 -0.73588719 0.10804913 79 -6.81 0.0001
Complete Case Analysis 12:17 Sunday, April 23, 2000 546
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
TI 1 0.00000000 . . . .
Tests of Fixed Effects
DATASET 3. MASTITIS IN DAIRY CATTLE 44
Source NDF DDF Type III F Pr > F
TI 1 79 46.39 0.0001
Last Observation Carried Forward 547
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TI 2 0 1
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 222.10149267
1 1 171.33415449 0.00000000
Convergence criteria met.
R Matrix for Subject 1
Row COL1 COL2
1 1.03858316 0.63835255
2 0.63835255 1.03858316
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
AR(1) IDENT 0.61463788 0.06015230 10.22 0.0001
Residual 1.03858316 0.11785263 8.81 0.0001
Model Fitting Information for YY
Description Value
Observations 214.0000
Log Likelihood -282.320
Akaike’s Information Criterion -284.320
Schwarz’s Bayesian Criterion -287.686
-2 Log Likelihood 564.6398
Null Model LRT Chi-Square 50.7673
Null Model LRT DF 1.0000
Null Model LRT P-Value 0.0000
Solution for Fixed Effects
DATASET 3. MASTITIS IN DAIRY CATTLE 45
Effect TI Estimate Std Error DF t Pr > |t|
INTERCEPT 6.31526919 0.09852099 106 64.10 0.0001
Last Observation Carried Forward 548
12:17 Sunday, April 23, 2000
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
TI 0 -0.55019603 0.08649246 106 -6.36 0.0001
TI 1 0.00000000 . . . .
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TI 1 106 40.46 0.0001
Unconditional Mean Imputation 549
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TI 2 0 1
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 197.62938561
1 1 163.44410735 0.00000000
Convergence criteria met.
R Matrix for Subject 1
Row COL1 COL2
1 0.92635458 0.48443961
2 0.48443961 0.92635458
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
AR(1) IDENT 0.52295268 0.07023539 7.45 0.0001
Residual 0.92635458 0.10106048 9.17 0.0001
DATASET 3. MASTITIS IN DAIRY CATTLE 46
Model Fitting Information for YY
Description Value
Observations 214.0000
Log Likelihood -278.375
Akaike’s Information Criterion -280.375
Schwarz’s Bayesian Criterion -283.741
-2 Log Likelihood 556.7498
Null Model LRT Chi-Square 34.1853
Null Model LRT DF 1.0000
Null Model LRT P-Value 0.0000
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
INTERCEPT 6.44348562 0.09304579 106 69.25 0.0001
Unconditional Mean Imputation 550
12:17 Sunday, April 23, 2000
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
TI 0 -0.67841246 0.09088505 106 -7.46 0.0001
TI 1 0.00000000 . . . .
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TI 1 106 55.72 0.0001
Conditional Mean Imputation 551
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TI 2 0 1
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 208.19212620
1 1 153.34854853 0.00000000
DATASET 3. MASTITIS IN DAIRY CATTLE 47
Convergence criteria met.
R Matrix for Subject 1
Row COL1 COL2
1 0.97322537 0.61631974
2 0.61631974 0.97322537
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
AR(1) IDENT 0.63327546 0.05790386 10.94 0.0001
Residual 0.97322537 0.11136442 8.74 0.0001
Model Fitting Information for YY
Description Value
Observations 214.0000
Log Likelihood -273.327
Akaike’s Information Criterion -275.327
Schwarz’s Bayesian Criterion -278.693
-2 Log Likelihood 546.6542
Null Model LRT Chi-Square 54.8436
Null Model LRT DF 1.0000
Null Model LRT P-Value 0.0000
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
INTERCEPT 6.48434231 0.09537067 106 67.99 0.0001
Conditional Mean Imputation 552
12:17 Sunday, April 23, 2000
Solution for Fixed Effects
Effect TI Estimate Std Error DF t Pr > |t|
TI 0 -0.71926916 0.08167701 106 -8.81 0.0001
TI 1 0.00000000 . . . .
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TI 1 106 77.55 0.0001
Available Case/Ignorable Analysis 553
DATASET 3. MASTITIS IN DAIRY CATTLE 48
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TI 2 0 1
ML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 197.91504041
1 2 164.89047899 0.00008734
2 1 164.88320081 0.00000002
3 1 164.88319889 0.00000000
Convergence criteria met.
R Matrix for Subject 1
Row COL1 COL2
1 1.04588712 0.58890927
2 0.58890927 1.04588712
Covariance Parameter Estimates (MLE)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
AR(1) IDENT 0.56307154 0.07233631 7.78 0.0001
Residual 1.04588712 0.12061328 8.67 0.0001
Model Fitting Information for YY
Description Value
Observations 187.0000
Log Likelihood -254.283
Akaike’s Information Criterion -256.283
Schwarz’s Bayesian Criterion -259.514
-2 Log Likelihood 508.5662
Null Model LRT Chi-Square 33.0318
Null Model LRT DF 1.0000
Null Model LRT P-Value 0.0000
Available Case/Ignorable Analysis 554
12:17 Sunday, April 23, 2000
Solution for Fixed Effects
DATASET 3. MASTITIS IN DAIRY CATTLE 49
Effect TI Estimate Std Error DF t Pr > |t|
INTERCEPT 6.47584805 0.10967069 106 59.05 0.0001
TI 0 -0.71077490 0.10389734 79 -6.84 0.0001
TI 1 0.00000000 . . . .
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TI 1 79 46.80 0.0001
Summary of Intraclass Correlations
The combined evidence from both approaches (heterogeneous and homogeneous variance structure) and all 5missing data strategies is as follows (estimates of correlation with their standard errors in parenthesis):
Method Heterogeneous Homogeneous
Complete Cases 0.591 (0.073) 0.581 (0.074)
LOCF 0.623 (0.059) 0.615 (0.060)
Unconditional Mean 0.524 (0.070) 0.523 (0.070)
Conditional Mean 0.637 (0.057) 0.633 (0.058)
Ignorable Analysis 0.581 (0.071) 0.563 (0.072)
Dataset 4
Age-related Macular Degeneration Study
4.1 Description of the Data
These data arise from a randomized multi-centric clinical trial comparing an experimental treatment (interferon-α) to a corresponding placebo in the treatment of patients with age-related macular degeneration. Throughoutthe analyses done, we focus on the comparison between placebo and the highest dose (6 million units daily) ofinterferon-α (Z), but the full results of this trial have been reported elsewhere (Pharmacological Therapy forMacular Degeneration Study Group 1997). Patients with macular degeneration progressively lose vision. In thetrial, the patients’ visual acuity was assessed at different time points (4 weeks, 12 weeks, 24 weeks, and 52 weeks)through their ability to read lines of letters on standardized vision charts. These charts display lines of 5 lettersof decreasing size, which the patient must read from top (largest letters) to bottom (smallest letters). Each linewith at least 4 letters correctly read is called one ‘line of vision.’ The patient’s visual acuity is the total numberof letters correctly read. The primary endpoint of the trial was the loss of at least 3 lines of vision at 1 year,compared to their baseline performance (a binary endpoint). The secondary endpoint of the trial was the visualacuity at 1 year (treated as a continuous endpoint).
Table 4.1: Age Related Macular Degeneration Trial. Loss of at least 3 lines of vision at 1 year according to loss ofat least 2 lines of vision at 6 months and according to randomized treatment group (placebo versus interferon-α).
12 months
Placebo Active
6 months 0 1 0 1
No event (0) 56 9 31 9
Event (1) 8 30 9 38
Table 4.2 shows the visual acuity (mean and standard error) by treatment group at baseline, at 6 months, andat 1 year. Visual acuity can be measured in several ways. First, one can record the number of letters read.Alternatively, dichotomized versions (at least 3 lines of vision lost, or at least 3 lines of vision lost) can be usedas well. Although there are 190 subjects with both month 6 and month 12 measurements available, the totalnumber of longitudinal profiles is 240, but only for 188 of these have the four follow-up measurements been made.
50
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 51
Table 4.2: Age Related Macular Degeneration Trial. Mean (standard error) of visual acuity at baseline, at 6months and at 1 year according to randomized treatment group (placebo versus interferon-α).
Time point Placebo Active Total
Baseline 55.3 (1.4) 54.6 (1.3) 55.0 (1.0)
6 months 49.3 (1.8) 45.5 (1.8) 47.5 (1.3)
1 year 44.4 (1.8) 39.1 (1.9) 42.0 (1.3)
allarmd.sas7bdat
1. crf: patient identification number
2. trt: treatment indicator (1: placebo, 4: interferon-α)
3. visual0, visual12, visual24, visual52: responses at baseline, 4, 12, 24, and 52 weeks
4. lesion: the number of lesions
References
Molenberghs, G. and Verbeke, G. (2005) Models for Discrete Longitudinal Data. New York: Springer.
4.2 Questions
1. Describe the various missingness patterns and discuss. Pay attention to the different status of completers,monotone sequences, and non-monotone sequences.
2. Formulate and fit a standard GEE and linearization-based GEE model. Apply CC, LOCF, and use the dataas they are. Pay attention to the choice of the working correlation structure and discuss the differencebetween model based and empirically corrected standard errors. The covariate effects of interest are time(unstructured) as well as treatment by time interaction.
3. Supplement the GEE analysis with a WGEE counterpart. Describe the differences and explain.
4. Discuss the relationship between the (absence of) evidence for MAR and the difference between the GEE–WGEE results.
5. Are these differences important for the conclusions drawn from the study?
6. Formulate and fit a random-intercepts model, with the same covariates included as for the GEE model. UseCC, LOCF, and direct likelihood. Discuss.
7. Supplement the WGEE analysis with an MI-GEE analysis, where the data are first multiply imputed andthen a standard GEE analysis is performed, before combining them into a single set of inferences.
8. Fit the random-intercepts logistic regression using the PQL and MQL methods, under ML and REML, andcompare the results.
9. Refit the model using numerical integration with an increasing number of quadrature points. Compareresults between Gaussian Quadrature, Laplace approximation, and adaptive Gaussian Quadrature. Extractthe Empirical Bayes estimates for the random-effects and compute summary statistics.
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 52
10. Test for random-slopes and treatment effect using a likelihood ratio test.
11. Plot the marginal average evolutions under the final model for the two treatment groups.
12. Formulate a GLMM in which the time variable is considered categorical and test for a treatment differenceat week 52.
4.3 Elements of Solution
4.3.1 Programs
1. Exploration of missing data mechanisms.
data armd14;
set allarmd;
diff4=visual4-visual0;
diff12=visual12-visual0;
diff24=visual24-visual0;
diff52=visual52-visual0;
bindif4=0; if diff4 <= 0 then bindif4=1;
bindif12=0;if diff12 <= 0 then bindif12=1;
bindif24=0;if diff24 <= 0 then bindif24=1;
bindif52=0;if diff52 <= 0 then bindif52=1;
if diff4=. then bindif4=.;
if diff12=. then bindif12=.;
if diff24=. then bindif24=.;
if diff52=. then bindif52=.;
if trt=1 then treat=1;
if trt=4 then treat=2;
subject=_n_;
run;
proc sort data=armd14;
by treat;
run;
proc mi data=armd14 seed=675938 simple nimpute=0;
title ’standard EM’;
em itprint outem=growthem1;
var diff4 diff12 diff24 diff52;
by treat;
run;
proc mi data=armd14 seed=675938 simple nimpute=0;
title ’EM with CC initial values’;
em itprint outem=growthem1 initial=cc;
var diff4 diff12 diff24 diff52;
by treat;
run;
2. Preparation of CC, LOCF and observed data datasets. Preparation of WGEE analysis.
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 53
/*
** we create a longitudinal dataset with four binary outcomes - complete & incomplete
**
*/
proc print data=allarmd;
run;
data armd11;
set allarmd;
diff4=visual4-visual0;
diff12=visual12-visual0;
diff24=visual24-visual0;
diff52=visual52-visual0;
bindif4=0; if diff4 <= 0 then bindif4=1;
bindif12=0;if diff12 <= 0 then bindif12=1;
bindif24=0;if diff24 <= 0 then bindif24=1;
bindif52=0;if diff52 <= 0 then bindif52=1;
if diff4=. then bindif4=.;
if diff12=. then bindif12=.;
if diff24=. then bindif24=.;
if diff52=. then bindif52=.;
if trt=1 then treat=1;
if trt=4 then treat=2;
run;
proc print data=armd11;
run;
/* switch from horizontal to vertical dataset */
data armd111;
set armd11;
array x (4) bindif4 bindif12 bindif24 bindif52;
do j=1 to 4;
bindif=x(j);
time=j;
subject=_n_;
output;
end;
run;
proc print data=armd111;
var subject bindif4 bindif12 bindif24 bindif52 treat time bindif;
run;
%macro cc(data=,id=,time=,response=,out=);
%if %bquote(&data)= %then %let data=&syslast;
proc freq data=&data noprint;
tables &id /out=freqsub;
tables &time / out=freqtime;
run;
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 54
proc iml;
use freqsub;
read all var {&id,count};
nsub = nrow(&id);
use freqtime;
read all var {&time,count};
ntime = nrow(&time);
use &data;
read all var {&id,&time,&response};
n = nrow(&response);
complete = j(n,1,1);
ind = 1;
do while (ind <= nsub);
j = 1;
do while (j <= ntime);
if (&response[(ind-1)*ntime+j]=.) then
complete[(ind-1)*ntime+1:(ind-1)*ntime+ntime]=0;
j = j+1;
end;
ind = ind+1;
end;
create help var {&id &time &response complete};
append;
quit;
data &out;
merge &data help;
if complete=0 then delete;
drop complete;
run;
%mend;
%cc(data=armd111,id=subject,time=time,response=bindif,out=armdcc);
proc print data=armdcc;
run;
%macro locf(data=,id=,time=,response=,out=);
%if %bquote(&data)= %then %let data=&syslast;
proc freq data=&data noprint;
tables &id /out=freqsub;
tables &time / out=freqtime;
run;
proc iml;
use freqsub;
read all var {&id,count};
nsub = nrow(&id);
use freqtime;
read all var {&time,count};
ntime = nrow(&time);
use &data;
read all var {&id,&time,&response};
n = nrow(&response);
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 55
locf = &response;
ind = 1;
print nsub;
print ntime;
do while (ind <= nsub);
j=2;
do while (j <= ntime);
if (locf[(ind-1)*ntime+j]=.) then locf[(ind-1)*ntime+j]=locf[(ind-1)*ntime+j-1];
j= j+1;
end;
ind = ind+1;
end;
create help var {&id &time &response locf};
append;
quit;
data &out;
merge &data help;
run;
%mend;
%locf(data=armd111,id=subject,time=time,response=bindif,out=armdlocf);
proc print data=armdlocf;
var subject treat time bindif locf;
run;
* WGEE: macro for creating variables "dropout" and "prev" */
%macro dropout(data=,id=,time=,response=,out=);
%if %bquote(&data)= %then %let data=&syslast;
proc freq data=&data noprint;
tables &id /out=freqid;
tables &time / out=freqtime;
run;
proc iml;
reset noprint;
use freqid;
read all var {&id};
nsub = nrow(&id);
use freqtime;
read all var {&time};
ntime = nrow(&time);
time = &time;
use &data;
read all var {&id &time &response};
n = nrow(&response);
dropout = j(n,1,0);
ind = 1;
do while (ind <= nsub);
j=1;
if (&response[(ind-1)*ntime+j]=.) then print "First Measurement is Missing";
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 56
if (&response[(ind-1)*ntime+j]^=.) then
do;
j = ntime;
do until (j=1);
if (&response[(ind-1)*ntime+j]=.) then
do;
dropout[(ind-1)*ntime+j]=1;
j = j-1;
end;
else j = 1;
end;
end;
ind = ind+1;
end;
prev = j(n,1,1);
prev[2:n] = &response[1:n-1];
i=1;
do while (i<=n);
if &time[i]=time[1] then prev[i]=.;
i = i+1;
end;
create help var {&id &time &response dropout prev};
append;
quit;
data &out;
merge &data help;
run;
%mend;
%dropout(data=armd111,id=subject,time=time,response=bindif,out=armdhlp);
proc genmod data=armdhlp descending;
class trt prev lesion time;
model dropout = prev trt lesion time / pred dist=b;
ods output obstats=pred;
ods listing exclude obstats;
run;
proc print data=pred;
run;
data pred;
set pred;
keep observation pred;
run;
data armdhlp;
merge pred armdhlp;
run;
proc print data=armdhlp;
run;
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 57
%macro dropwgt(data=,id=,time=,pred=,dropout=,out=);
%if %bquote(&data)= %then %let data=&syslast;
proc freq data=&data noprint;
tables &id /out=freqid;
tables &time / out=freqtime;
run;
proc iml;
reset noprint;
use freqid;
read all var {&id};
nsub = nrow(&id);
use freqtime;
read all var {&time};
ntime = nrow(&time);
time = &time;
use &data;
read all var {&id &time &pred &dropout};
n = nrow(&pred);
wi = j(n,1,1);
ind = 1;
do while (ind <= nsub);
wihlp = 1;
stay = 1;
/* first measurement */
if (&dropout[(ind-1)*ntime+2]=1)
then do;
wihlp = pred[(ind-1)*ntime+2];
stay = 0;
end;
else if (&dropout[(ind-1)*ntime+2]=0)
then wihlp = 1-pred[(ind-1)*ntime+2];
/* second to penultimate measurement */
j=2;
do while ((j <= ntime-1) & stay);
if (&dropout[(ind-1)*ntime+j+1]=1)
then do;
wihlp = wihlp*pred[(ind-1)*ntime+j+1];
stay = 0;
end;
else if (&dropout[(ind-1)*ntime+j+1]=0)
then wihlp = wihlp*(1-pred[(ind-1)*ntime+j+1]);
j = j+1;
end;
j = 1;
do while (j <= ntime);
wi[(ind-1)*ntime+j]=wihlp;
j = j+1;
end;
ind = ind+1;
end;
create help var {&id &time &pred &dropout wi};
append;
quit;
data &out;
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 58
merge &data help;
data &out;
set &out;
wi=1/wi;
run;
%mend;
%dropwgt(data=armdhlp,id=subject,time=time,pred=pred,dropout=dropout,out=armdwgee);
proc print data=armdwgee;
var subject time bindif dropout prev pred wi;
run;
3. CC, LOCF, and observed data analyses.
/* LOCF, CC, direct likelihood, (W)GEE analysis */
proc genmod data=armdcc;
title ’CC - GEE’;
class time treat subject;
model bindif = time treat*time / noint dist=binomial;
repeated subject=subject / withinsubject=time type=exch modelse;
run;
proc glimmix data=armdcc;
title ’CC - GEE - linearized version’;
nloptions maxiter=50 technique=newrap;
class time treat subject;
model bindif = time treat*time / noint solution dist=binary;
random _residual_ / subject=subject type=cs;
run;
proc glimmix data=armdcc empirical;
title ’CC - GEE - linearized version - empirical’;
nloptions maxiter=50 technique=newrap;
class time treat subject;
model bindif = time treat*time / noint solution dist=binary;
random _residual_ / subject=subject type=cs;
run;
proc genmod data=armdlocf;
title ’LOCF - GEE’;
class time treat subject;
model locf = time treat*time / noint dist=binomial;
repeated subject=subject / withinsubject=time type=exch modelse;
run;
proc glimmix data=armdlocf;
title ’LOCF - GEE - linearized version’;
nloptions maxiter=50 technique=newrap;
class time treat subject;
model locf = time treat*time / noint solution dist=binary;
random _residual_ / subject=subject type=cs;
run;
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 59
proc glimmix data=armdlocf empirical;
title ’LOCF - GEE - linearized version - empirical’;
nloptions maxiter=50 technique=newrap;
class time treat subject;
model locf = time treat*time / noint solution dist=binary ;
random _residual_ / subject=subject type=cs;
run;
proc genmod data=armdwgee;
title ’data as is - GEE’;
class time treat subject;
model bindif = time treat*time / noint dist=binomial;
repeated subject=subject / withinsubject=time type=exch modelse;
run;
proc glimmix data=armdwgee;
title ’data as is - GEE - linearized version’;
nloptions maxiter=50 technique=newrap;
class time treat subject;
model bindif = time treat*time / noint solution dist=binary;
random _residual_ / subject=subject type=cs;
run;
proc glimmix data=armdwgee empirical;
title ’data as is - GEE - linearized version - empirical’;
nloptions maxiter=50 technique=newrap;
class time treat subject;
model bindif = time treat*time / noint solution dist=binary ;
random _residual_ / subject=subject type=cs;
run;
proc genmod data=armdwgee;
title ’data as is - WGEE’;
scwgt wi;
class time treat subject;
model bindif = time treat*time / noint dist=binomial;
repeated subject=subject / withinsubject=time type=exch modelse;
run;
proc glimmix data=armdwgee;
title ’data as is - WGEE - linearized version’;
nloptions maxiter=50 technique=newrap;
weight wi;
class time treat subject;
model bindif = time treat*time / noint solution dist=binary;
random _residual_ / subject=subject type=cs;
run;
proc glimmix data=armdwgee empirical;
title ’data as is - WGEE - linearized version - empirical’;
weight wi;
nloptions maxiter=50 technique=newrap;
class time treat subject;
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 60
model bindif = time treat*time / noint solution dist=binary ;
random _residual_ / subject=subject type=cs;
run;
proc glimmix data=armdcc method=rspl;
title ’CC - mixed - PQL’;
nloptions maxiter=50 technique=newrap;
class time treat subject;
model bindif = time treat*time / noint solution dist=binary;
random intercept / subject=subject type=un g gcorr;
run;
proc glimmix data=armdcc method=rspl;
title ’CC - mixed - PQL’;
nloptions maxiter=50 technique=newrap;
class time treat subject;
model bindif = time treat*time / noint solution dist=binary;
random intercept / subject=subject type=un g gcorr;
run;
proc glimmix data=armdlocf method=rspl;
title ’LOCF - mixed - PQL’;
nloptions maxiter=50 technique=newrap;
class time treat subject;
model locf = time treat*time / noint solution dist=binary;
random intercept / subject=subject type=un g gcorr;
run;
proc glimmix data=armdwgee method=rspl;
title ’as is - mixed - PQL’;
nloptions maxiter=50 technique=newrap;
class time treat subject;
model bindif = time treat*time / noint solution dist=binary;
random intercept / subject=subject type=un g gcorr;
run;
data help;
set armdcc;
time1=0;
time2=0;
time3=0;
time4=0;
if time=1 then time1=1;
if time=2 then time2=1;
if time=3 then time3=1;
if time=4 then time4=1;
run;
proc nlmixed data=help qpoints=20 maxiter=100 technique=newrap;
title ’CC - mixed - numerical integration’;
eta = beta11*time1+beta12*time2+beta13*time3+beta14*time4
+b
+(beta21*time1+beta22*time2+beta23*time3+beta24*time4)*(2-treat);
p = exp(eta)/(1+exp(eta));
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 61
model bindif ~ binary(p);
random b ~ normal(0,tau*tau) subject=subject;
estimate ’tau^2’ tau*tau;
run;
data help;
set armdlocf;
time1=0;
time2=0;
time3=0;
time4=0;
if time=1 then time1=1;
if time=2 then time2=1;
if time=3 then time3=1;
if time=4 then time4=1;
run;
proc nlmixed data=help qpoints=20 maxiter=100 technique=newrap;
title ’LOCF - mixed - numerical integration’;
eta = beta11*time1+beta12*time2+beta13*time3+beta14*time4
+b
+(beta21*time1+beta22*time2+beta23*time3+beta24*time4)*(2-treat);
p = exp(eta)/(1+exp(eta));
model locf ~ binary(p);
random b ~ normal(0,tau*tau) subject=subject;
estimate ’tau^2’ tau*tau;
run;
data help;
set armdwgee;
time1=0;
time2=0;
time3=0;
time4=0;
if time=1 then time1=1;
if time=2 then time2=1;
if time=3 then time3=1;
if time=4 then time4=1;
run;
proc nlmixed data=help qpoints=20 maxiter=100 technique=newrap;
title ’as is - mixed - numerical integration’;
eta = beta11*time1+beta12*time2+beta13*time3+beta14*time4
+b
+(beta21*time1+beta22*time2+beta23*time3+beta24*time4)*(2-treat);
p = exp(eta)/(1+exp(eta));
model bindif ~ binary(p);
random b ~ normal(0,tau*tau) subject=subject;
estimate ’tau^2’ tau*tau;
run;
4. Multiple imputation.
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 62
libname m ’\bartsas\mvboek’ ;
options nocenter;
data m.armd13;
set m.allarmd;
diff4=visual4-visual0;
diff12=visual12-visual0;
diff24=visual24-visual0;
diff52=visual52-visual0;
if trt=1 then treat=1;
if trt=4 then treat=2;
subject=_n_;
run;
proc sort data=m.armd13;
by treat;
run;
proc mi data=m.armd13 seed=486048 simple out=m.armd13a nimpute=10 round=0.1;
var lesion diff4 diff12 diff24 diff52;
by treat;
run;
data m.armd13a;
set m.armd13a;
bindif4=0; if diff4 <= 0 then bindif4=1;
bindif12=0;if diff12 <= 0 then bindif12=1;
bindif24=0;if diff24 <= 0 then bindif24=1;
bindif52=0;if diff52 <= 0 then bindif52=1;
if diff4=. then bindif4=.;
if diff12=. then bindif12=.;
if diff24=. then bindif24=.;
if diff52=. then bindif52=.;
run;
proc print data=m.armd13a;
var _imputation_ diff4 diff12 diff24 diff52 bindif4 bindif12 bindif24 bindif52;
where (subject=1);
run;
data m.armd13b;
set m.armd13a;
array x (4) bindif4 bindif12 bindif24 bindif52;
array y (4) diff4 diff12 diff24 diff52;
do j=1 to 4;
bindif=x(j);
diff=y(j);
time=j;
output;
end;
run;
proc print data=m.armd13b;
title ’Dataset after imputation’;
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 63
var _imputation_ subject time diff bindif;
run;
data m.armd13c;
set m.armd13b;
time1=0;
time2=0;
time3=0;
time4=0;
trttime1=0;
trttime2=0;
trttime3=0;
trttime4=0;
if time=1 then time1=1;
if time=2 then time2=1;
if time=3 then time3=1;
if time=4 then time4=1;
if (time=1 & treat=1) then trttime1=1;
if (time=2 & treat=1) then trttime2=1;
if (time=3 & treat=1) then trttime3=1;
if (time=4 & treat=1) then trttime4=1;
run;
proc sort data=m.armd13c;
by _imputation_ subject time;
run;
proc genmod data=m.armd13c;
title ’GEE after multiple imputation’;
class time subject;
by _imputation_;
model bindif = time1 time2 time3 time4 trttime1 trttime2 trttime3 trttime4
/ noint dist=binomial covb;
repeated subject=subject / withinsubject=time type=exch modelse;
ods output ParameterEstimates=gmparms parminfo=gmpinfo CovB=gmcovb;
run;
data gmpinfo;
set gmpinfo;
if parameter=’Prm1’ then delete;
run;
proc print data=gmparms;
run;
proc print data=gmcovb;
run;
proc print data=gmpinfo;
run;
proc mianalyze parms=gmparms covb=gmcovb parminfo=gmpinfo wcov bcov tcov;
modeleffects time1 time2 time3 time4 trttime1 trttime2 trttime3 trttime4;
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 64
run;
proc nlmixed data=m.armd13c qpoints=20 maxiter=100 technique=newrap cov ecov;
title ’NLMIXED after multiple imputation’;
by _imputation_;
eta = beta11*time1+beta12*time2+beta13*time3+beta14*time4
+b
+beta21*trttime1+beta22*trttime2+beta23*trttime3+beta24*trttime4;
p = exp(eta)/(1+exp(eta));
model bindif ~ binary(p);
random b ~ normal(0,tau*tau) subject=subject;
estimate ’tau2’ tau*tau;
ods output ParameterEstimates=nlparms CovMatParmEst=nlcovb
AdditionalEstimates=nlparmsa CovMatAddEst=nlcovba;
run;
proc mianalyze parms=nlparms covb=nlcovb;
title ’MIANALYZE for NLMIXED’;
modeleffects beta11 beta12 beta13 beta14 beta21 beta22 beta23 beta24 tau;
run;
5. Fit GLMMs using PQL and MQL.
proc glimmix data = m.armd method = RSPL;
title ’PQL REML’;
class subject;
model bindif (event = ’1’) = timec treat * timec / dist = binary solution;
random intercept / subject = subject;
run;
proc glimmix data = m.armd method = MSPL noclprint noitprint;
title ’PQL ML’;
class subject;
model bindif (event = ’1’) = timec treat * timec / dist = binary solution;
random intercept / subject = subject;
run;
proc glimmix data = m.armd method = RMPL noclprint noitprint;
title ’MQL REML’;
class subject;
model bindif (event = ’1’) = timec treat * timec / dist = binary solution;
random intercept / subject = subject;
run;
proc glimmix data = m.armd method = MMPL noclprint noitprint;
title ’MQL ML’;
class subject;
model bindif (event = ’1’) = timec treat * timec / dist = binary solution;
random intercept / subject = subject;
run;
6. Fit GLMMs using Gaussian Quadrature.
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 65
*Get initial values for GLMMs;
proc genmod data = m.armd descending;
title ’Initial Values’;
model bindif = timec treat * timec / dist = bin;
run;
* Gauss-Quadrature non-adaptive Q = 25;
proc nlmixed data = m.armd noad qpoints = 25;
title ’MML GQ 25’;
parms beta0 = 0.5670 beta1 = 0.0098 beta2 = 0.0133 sigmab = 2;
eta = beta0 + b + beta1 * timec + beta2 * treat * timec;
pr = exp(eta) / (1 + exp(eta));
model bindif ~ binary(pr);
random b ~ normal(0, sigmab**2) subject = subject;
estimate ’sigmab^2’ sigmab**2;
run;
* Gauss-Quadrature non-adaptive Q = 51;
proc nlmixed data = m.armd noad qpoints = 51;
title ’MML GQ 51’;
parms beta0 = 0.5670 beta1 = 0.0098 beta2 = 0.0133 sigmab = 2;
eta = beta0 + b + beta1 * timec + beta2 * treat * timec;
pr = exp(eta) / (1 + exp(eta));
model bindif ~ binary(pr);
random b ~ normal(0, sigmab**2) subject = subject;
estimate ’sigmab^2’ sigmab**2;
run;
* Laplace approximation;
proc nlmixed data = m.armd qpoints = 1;
title ’MML Laplace’;
parms beta0 = 0.5670 beta1 = 0.0098 beta2 = 0.0133 sigmab = 2;
eta = beta0 + b + beta1 * timec + beta2 * treat * timec;
pr = exp(eta) / (1 + exp(eta));
model bindif ~ binary(pr);
random b ~ normal(0, sigmab**2) subject = subject;
estimate ’sigmab^2’ sigmab**2;
run;
* Gauss-Quadrature adaptive Q = 5;
proc nlmixed data = m.armd qpoints = 5;
title ’MML AGQ 5’;
parms beta0 = 0.5670 beta1 = 0.0098 beta2 = 0.0133 sigmab = 2;
eta = beta0 + b + beta1 * timec + beta2 * treat * timec;
pr = exp(eta) / (1 + exp(eta));
model bindif ~ binary(pr);
random b ~ normal(0, sigmab**2) subject = subject;
estimate ’sigmab^2’ sigmab**2;
run;
* Gauss-Quadrature adaptive Q = 11;
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 66
proc nlmixed data = m.armd qpoints = 11 ebopt;
title ’MML AGQ 11’;
parms beta0 = 0.5670 beta1 = 0.0098 beta2 = 0.0133 sigmab = 2;
eta = beta0 + b + beta1 * timec + beta2 * treat * timec;
pr = exp(eta) / (1 + exp(eta));
model bindif ~ binary(pr);
random b ~ normal(0, sigmab**2) subject = subject out = EB;
estimate ’sigmab^2’ sigmab**2;
run;
proc univariate data = EB;
var estimate;
histogram estimate;
title ’Empirical Bayes Estimates’;
run;
7. Likelihood Ratio Tests for random-slopes and treatment.
* Test for random slopes;
proc nlmixed data = m.armd qpoints = 11;
title ’MML AGQ 11 / Slopes’;
parms beta0 = 0.5670 beta1 = 0.0098 beta2 = 0.0133
sigmab1 = 2 sigmab2 = 1 rho = -0.4;
eta = beta0 + b1 + beta1 * timec + b2 * timec + beta2 * treat * timec;
pr = exp(eta) / (1 + exp(eta));
model bindif ~ binary(pr);
random b1 b2 ~ normal([0, 0], [sigmab1**2, rho * sigmab1 * sigmab2, sigmab2**2])
subject = subject;
run;
data LRT;
L01 = -2 * (-449.285125 - (-443.794458));
df = 2;
pval = 1 - probchi(L01, 2);
run;
proc print data = LRT;
run;
* Increase quadrature points and test again;
proc nlmixed data = m.armd qpoints = 21;
title ’MML AGQ 21’;
parms beta0 = 0.5670 beta1 = 0.0098 beta2 = 0.0133 sigmab = 2;
eta = beta0 + b + beta1 * timec + beta2 * treat * timec;
pr = exp(eta) / (1 + exp(eta));
model bindif ~ binary(pr);
random b ~ normal(0, sigmab**2) subject = subject;
run;
proc nlmixed data = m.armd qpoints = 21;
title ’MML AGQ 21 / Slopes’;
parms beta0 = 0.5670 beta1 = 0.0098 beta2 = 0.0133
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 67
sigmab1 = 2 sigmab2 = 1 rho = -0.4;
eta = beta0 + b1 + beta1 * timec + b2 * timec + beta2 * treat * timec;
pr = exp(eta) / (1 + exp(eta));
model bindif ~ binary(pr);
random b1 b2 ~ normal([0, 0], [sigmab1**2, rho * sigmab1 * sigmab2, sigmab2**2])
subject = subject;
run;
data LRT;
L01 = -2 * (-449.295733 - (-443.902654));
df = 2;
pval = 1 - probchi(L01, 2);
run;
proc print data = LRT;
run;
* Test for a treatment effect;
proc nlmixed data = m.armd qpoints = 21;
title ’MML AGQ 21 / No Treatment’;
parms beta0 = 0.5670 beta1 = 0.0098 sigmab1 = 2 sigmab2 = 1 rho = -0.4;
eta = beta0 + b1 + beta1 * timec + b2 * timec;
pr = exp(eta) / (1 + exp(eta));
model bindif ~ binary(pr);
random b1 b2 ~ normal([0, 0], [sigmab1**2, rho * sigmab1 * sigmab2, sigmab2**2])
subject = subject;
run;
data LRT;
L01 = 889.7 - 887.8;
df = 2;
pval = 1 - probchi(L01, 2);
run;
proc print data = LRT;
run;
8. Calculate and plot the marginal average evolutions.
%inc ’C:\ARMD\MVN.sas’;
data mean_b;
input m1;
cards;
0
0
run;
data var_b;
input m1-m2;
cards;
5.354133 -0.006765938
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 68
-0.006765938 0.006379217
run;
%mvn(varcov = var_b, means = mean_b, n = 4000, sample = b, seed = -1);
data b;
set b;
do t = 1 to 4 by 1;
output;
end;
drop t;
run;
data SimulateValues;
do treat = 0 to 1 by 1;
do subject = 1 to 2000 by 1;
do t = 1 to 4 by 1;
output;
end;
end;
end;
run;
proc sort data = SimulateValues;
by subject;
run;
data SimulateValues;
merge SimulateValues b;
run;
proc sort data = SimulateValues;
by t treat;
run;
data SimulateValues;
set SimulateValues;
timec = 0;
if t = 1 then timec = 4;
if t = 2 then timec = 12;
if t = 3 then timec = 24;
if t = 4 then timec = 52;
if treat = 0 then
y = 1 / (1 + exp(-(0.7860 + col1 + (0.04966 + col2)*timec)));
else
y = 1 / (1 + exp(-(0.7860 + col1 + (0.07458 + col2)*timec)));
run;
proc means data = SimulateValues;
var y;
by timec treat;
output out = out;
run;
proc gplot data = out;
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 69
plot y * timec = treat / haxis = axis1 vaxis = axis2 legend = legend1;
axis1 label = (h = 2 ’Time’) value = (h = 1.5) order = (3 to 53 by 10)
minor = none;
axis2 label = (h = 2 A = 90 ’P(Y = 1)’) value = (h = 1.5)
order = (0.6 to 0.9 by 0.1) minor = none;
legend1 label = (h = 1.5 ’Treatment: ’) value = (h = 1.5 ’A’ ’B’);
title h = 2.5 ’Marginal average evolutions (GLMM)’;
symbol1 c = black i = join w = 5 l = 1 mode = include;
symbol2 c = black i = join w = 5 l = 2 mode = include;
where _stat_ = ’MEAN’;
run; quit; run;
9. Test at week 52.
data m.armd52;
set m.armd;
time12 = 0;
time24 = 0;
time52 = 0;
if timec = 12 then time12 = 1;
if timec = 24 then time24 = 1;
if timec = 52 then time52 = 1;
run;
proc genmod data = m.armd52 descending;
title ’Initial Values’;
model bindif = time12 time24 time52 time12*treat
time24*treat time52*treat / dist = bin;
run;
proc nlmixed data = m.armd52 qpoints = 21;
title ’Time as factor’;
parms beta0 = 0.7522 beta1 = -0.3538 beta2 = -0.1253 beta3 = 0.5190
beta4 = 0.6288 beta5 = 0.4457 beta6 = 0.4205 sigmab = 2;
eta = beta0 + b + beta1 * time12 + beta2 * time24 + beta3 * time52 +
(beta4 * time12 + beta5 * time24 + beta6 * time52) * treat;
pr = exp(eta) / (1 + exp(eta));
model bindif ~ binary(pr);
random b ~ normal(0, sigmab**2) subject = subject;
estimate ’MrgTrEff’ beta6 / sqrt(0.345843 * sigmab**2 + 1);
run;
4.3.2 SAS Output
1. Exploration of missing data mechanism
standard EM
treat=1
The MI Procedure
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 70
Model Information
Data Set M.ARMD14
Method MCMC
Multiple Imputation Chain Single Chain
Initial Estimates for MCMC EM Posterior Mode
Start Starting Value
Prior Jeffreys
Number of Imputations 0
Number of Burn-in Iterations 200
Number of Iterations 100
Seed for random number generator 675938
Missing Data Patterns
Group diff4 diff12 diff24 diff52 Freq Percent
1 X X X X 102 85.71
2 X X X . 9 7.56
3 X X . X 2 1.68
4 X X . . 3 2.52
5 X . . . 1 0.84
6 . X X X 1 0.84
7 O O O O 1 0.84
Missing Data Patterns
-------------------------Group Means------------------------
Group diff4 diff12 diff24 diff52
1 -0.921569 -2.313725 -5.598039 -10.960784
2 -1.222222 2.111111 -7.666667 .
3 -12.500000 -19.000000 . -18.500000
4 -4.000000 -4.000000 . .
5 -10.000000 . . .
6 . 1.000000 1.000000 -19.000000
7 . . . .
Univariate Statistics
--Missing Values--
Variable N Mean Std Dev Minimum Maximum Count Percent
diff4 117 -1.29915 7.71839 -33.00000 30.00000 2 1.68
diff12 117 -2.27350 11.73458 -38.00000 31.00000 2 1.68
diff24 112 -5.70536 13.82819 -54.00000 26.00000 7 5.88
diff52 105 -11.18095 16.42921 -59.00000 23.00000 14 11.76
standard EM
treat=1
The MI Procedure
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 71
Pairwise Correlations
diff4 diff12 diff24 diff52
diff4 1.000000000 0.574952060 0.378557649 0.344100362
diff12 0.574952060 1.000000000 0.556745963 0.524513959
diff24 0.378557649 0.556745963 1.000000000 0.772469673
diff52 0.344100362 0.524513959 0.772469673 1.000000000
Initial Parameter Estimates for EM
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -1.299145 -2.273504 -5.705357 -11.180952
COV diff4 59.573534 0 0 0
COV diff12 0 137.700413 0 0
COV diff24 0 0 191.218710 0
COV diff52 0 0 0 269.918864
EM (MLE) Iteration History
_Iteration_ -2 Log L diff4 diff12 diff24 diff52
0 2677.623690 -1.299145 -2.273504 -5.705357 -11.180952
1 2499.142589 -1.299145 -2.273504 -5.705357 -11.180952
2 2490.124996 -1.288106 -2.337030 -5.920341 -11.287948
3 2489.821035 -1.284122 -2.338551 -5.968896 -11.326957
4 2489.809193 -1.282958 -2.338624 -5.981039 -11.336978
5 2489.808488 -1.282661 -2.338637 -5.984320 -11.339102
6 2489.808431 -1.282579 -2.338640 -5.985249 -11.339499
7 2489.808426 -1.282555 -2.338641 -5.985521 -11.339563
8 2489.808426 -1.282547 -2.338641 -5.985603 -11.339571
9 2489.808426 -1.282544 -2.338641 -5.985628 -11.339571
EM (MLE) Parameter Estimates
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -1.282544 -2.338641 -5.985628 -11.339571
COV diff4 58.922448 51.511233 47.562350 47.117941
COV diff12 51.511233 136.639243 96.740432 106.108044
COV diff24 47.562350 96.740432 198.718732 184.115237
COV diff52 47.117941 106.108044 184.115237 279.107171
standard EM
treat=1
The MI Procedure
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 72
EM (Posterior Mode) Estimates
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -1.282517 -2.338656 -5.985517 -11.339728
COV diff4 56.514446 49.417496 45.626747 45.202035
COV diff12 49.417496 131.054420 92.785565 101.774088
COV diff24 45.626747 92.785565 190.400964 176.476791
COV diff52 45.202035 101.774088 176.476791 267.124726
standard EM
treat=2
The MI Procedure
Model Information
Data Set M.ARMD14
Method MCMC
Multiple Imputation Chain Single Chain
Initial Estimates for MCMC EM Posterior Mode
Start Starting Value
Prior Jeffreys
Number of Imputations 0
Number of Burn-in Iterations 200
Number of Iterations 100
Seed for random number generator 675938
Missing Data Patterns
Group diff4 diff12 diff24 diff52 Freq Percent
1 X X X X 86 71.07
2 X X X . 15 12.40
3 X X . X 2 1.65
4 X X . . 5 4.13
5 X . . X 1 0.83
6 X . . . 5 4.13
7 . X X X 1 0.83
8 . X . . 1 0.83
9 O O O O 5 4.13
Missing Data Patterns
-------------------------Group Means------------------------
Group diff4 diff12 diff24 diff52
1 -3.244186 -4.662791 -8.325581 -15.127907
2 -7.200000 -14.600000 -13.133333 .
3 5.000000 3.000000 . -30.000000
4 -1.400000 -6.200000 . .
5 4.000000 . . -14.000000
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 73
6 -4.000000 . . .
7 . -1.000000 -12.000000 -18.000000
8 . -1.000000 . .
9 . . . .
standard EM
treat=2
The MI Procedure
Univariate Statistics
--Missing Values--
Variable N Mean Std Dev Minimum Maximum Count Percent
diff4 114 -3.50877 8.86002 -38.00000 23.00000 7 5.79
diff12 110 -5.88182 11.62387 -46.00000 14.00000 11 9.09
diff24 102 -9.06863 14.08479 -52.00000 26.00000 19 15.70
diff52 90 -15.47778 15.38511 -49.00000 17.00000 31 25.62
Pairwise Correlations
diff4 diff12 diff24 diff52
diff4 1.000000000 0.613307315 0.510262505 0.288867147
diff12 0.613307315 1.000000000 0.771255576 0.526190089
diff24 0.510262505 0.771255576 1.000000000 0.728372871
diff52 0.288867147 0.526190089 0.728372871 1.000000000
Initial Parameter Estimates for EM
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -3.508772 -5.881818 -9.068627 -15.477778
COV diff4 78.499922 0 0 0
COV diff12 0 135.114345 0 0
COV diff24 0 0 198.381382 0
COV diff52 0 0 0 236.701748
EM (MLE) Iteration History
_Iteration_ -2 Log L diff4 diff12 diff24 diff52
0 2480.678086 -3.508772 -5.881818 -9.068627 -15.477778
1 2300.270300 -3.508772 -5.881818 -9.068627 -15.477778
2 2278.786779 -3.477478 -5.852476 -8.941456 -15.797125
3 2274.350562 -3.472907 -5.850379 -8.961648 -15.957037
4 2273.402622 -3.472710 -5.851200 -8.988433 -16.028507
5 2273.203404 -3.472699 -5.851816 -9.003220 -16.062034
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 74
6 2273.160311 -3.472669 -5.852158 -9.010063 -16.078693
7 2273.150702 -3.472645 -5.852336 -9.013093 -16.087193
8 2273.148517 -3.472630 -5.852426 -9.014439 -16.091541
9 2273.148015 -3.472622 -5.852472 -9.015047 -16.093748
10 2273.147899 -3.472618 -5.852494 -9.015327 -16.094857
11 2273.147872 -3.472616 -5.852505 -9.015458 -16.095408
12 2273.147866 -3.472615 -5.852511 -9.015520 -16.095681
standard EM
treat=2
The MI Procedure
EM (MLE) Iteration History
_Iteration_ -2 Log L diff4 diff12 diff24 diff52
13 2273.147865 -3.472615 -5.852513 -9.015550 -16.095814
14 2273.147864 -3.472615 -5.852515 -9.015564 -16.095880
15 2273.147864 -3.472614 -5.852515 -9.015571 -16.095911
EM (MLE) Parameter Estimates
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -3.472614 -5.852515 -9.015571 -16.095911
COV diff4 77.341311 65.693484 63.603263 53.184996
COV diff12 65.693484 139.657824 126.204014 116.793951
COV diff24 63.603263 126.204014 194.336855 181.980490
COV diff52 53.184996 116.793951 181.980490 283.052328
EM (Posterior Mode) Estimates
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -3.472576 -5.852548 -9.016530 -16.095481
COV diff4 74.112751 62.983750 60.970726 51.001689
COV diff12 62.983750 133.719788 120.846899 111.863551
COV diff24 60.970726 120.846899 185.801334 174.099672
COV diff52 51.001689 111.863551 174.099672 269.756733
EM with CC initial values
treat=1
The MI Procedure
Model Information
Data Set M.ARMD14
Method MCMC
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 75
Multiple Imputation Chain Single Chain
Initial Estimates for MCMC EM Posterior Mode
Start Starting Value
Prior Jeffreys
Number of Imputations 0
Number of Burn-in Iterations 200
Number of Iterations 100
Seed for random number generator 675938
Missing Data Patterns
Group diff4 diff12 diff24 diff52 Freq Percent
1 X X X X 102 85.71
2 X X X . 9 7.56
3 X X . X 2 1.68
4 X X . . 3 2.52
5 X . . . 1 0.84
6 . X X X 1 0.84
7 O O O O 1 0.84
Missing Data Patterns
-------------------------Group Means------------------------
Group diff4 diff12 diff24 diff52
1 -0.921569 -2.313725 -5.598039 -10.960784
2 -1.222222 2.111111 -7.666667 .
3 -12.500000 -19.000000 . -18.500000
4 -4.000000 -4.000000 . .
5 -10.000000 . . .
6 . 1.000000 1.000000 -19.000000
7 . . . .
Univariate Statistics
--Missing Values--
Variable N Mean Std Dev Minimum Maximum Count Percent
diff4 117 -1.29915 7.71839 -33.00000 30.00000 2 1.68
diff12 117 -2.27350 11.73458 -38.00000 31.00000 2 1.68
diff24 112 -5.70536 13.82819 -54.00000 26.00000 7 5.88
diff52 105 -11.18095 16.42921 -59.00000 23.00000 14 11.76
EM with CC initial values
treat=1
The MI Procedure
Pairwise Correlations
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 76
diff4 diff12 diff24 diff52
diff4 1.000000000 0.574952060 0.378557649 0.344100362
diff12 0.574952060 1.000000000 0.556745963 0.524513959
diff24 0.378557649 0.556745963 1.000000000 0.772469673
diff52 0.344100362 0.524513959 0.772469673 1.000000000
Initial Parameter Estimates for EM
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -0.921569 -2.313725 -5.598039 -10.960784
COV diff4 47.756164 35.628810 38.542419 38.838478
COV diff12 35.628810 122.791691 84.968938 97.408464
COV diff24 38.542419 84.968938 188.361580 176.993982
COV diff52 38.838478 97.408464 176.993982 275.820229
EM (MLE) Iteration History
_Iteration_ -2 Log L diff4 diff12 diff24 diff52
0 2494.806915 -0.921569 -2.313725 -5.598039 -10.960784
1 2489.822930 -1.282544 -2.331244 -5.984559 -11.332561
2 2489.809128 -1.282766 -2.338521 -5.987990 -11.341407
3 2489.808461 -1.282606 -2.338637 -5.986186 -11.340144
4 2489.808427 -1.282561 -2.338640 -5.985746 -11.339711
5 2489.808426 -1.282548 -2.338641 -5.985657 -11.339603
6 2489.808426 -1.282545 -2.338641 -5.985641 -11.339577
EM (MLE) Parameter Estimates
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -1.282545 -2.338641 -5.985641 -11.339577
COV diff4 58.922445 51.511232 47.563032 47.118620
COV diff12 51.511232 136.639243 96.741241 106.108805
COV diff24 47.563032 96.741241 198.720008 184.116452
COV diff52 47.118620 106.108805 184.116452 279.108439
EM with CC initial values
treat=1
The MI Procedure
EM (Posterior Mode) Estimates
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -1.282517 -2.338656 -5.985517 -11.339728
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 77
COV diff4 56.514446 49.417496 45.626747 45.202035
COV diff12 49.417496 131.054420 92.785566 101.774088
COV diff24 45.626747 92.785566 190.400966 176.476791
COV diff52 45.202035 101.774088 176.476791 267.124727
EM with CC initial values
treat=2
The MI Procedure
Model Information
Data Set M.ARMD14
Method MCMC
Multiple Imputation Chain Single Chain
Initial Estimates for MCMC EM Posterior Mode
Start Starting Value
Prior Jeffreys
Number of Imputations 0
Number of Burn-in Iterations 200
Number of Iterations 100
Seed for random number generator 675938
Missing Data Patterns
Group diff4 diff12 diff24 diff52 Freq Percent
1 X X X X 86 71.07
2 X X X . 15 12.40
3 X X . X 2 1.65
4 X X . . 5 4.13
5 X . . X 1 0.83
6 X . . . 5 4.13
7 . X X X 1 0.83
8 . X . . 1 0.83
9 O O O O 5 4.13
Missing Data Patterns
-------------------------Group Means------------------------
Group diff4 diff12 diff24 diff52
1 -3.244186 -4.662791 -8.325581 -15.127907
2 -7.200000 -14.600000 -13.133333 .
3 5.000000 3.000000 . -30.000000
4 -1.400000 -6.200000 . .
5 4.000000 . . -14.000000
6 -4.000000 . . .
7 . -1.000000 -12.000000 -18.000000
8 . -1.000000 . .
9 . . . .
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 78
EM with CC initial values
treat=2
The MI Procedure
Univariate Statistics
--Missing Values--
Variable N Mean Std Dev Minimum Maximum Count Percent
diff4 114 -3.50877 8.86002 -38.00000 23.00000 7 5.79
diff12 110 -5.88182 11.62387 -46.00000 14.00000 11 9.09
diff24 102 -9.06863 14.08479 -52.00000 26.00000 19 15.70
diff52 90 -15.47778 15.38511 -49.00000 17.00000 31 25.62
Pairwise Correlations
diff4 diff12 diff24 diff52
diff4 1.000000000 0.613307315 0.510262505 0.288867147
diff12 0.613307315 1.000000000 0.771255576 0.526190089
diff24 0.510262505 0.771255576 1.000000000 0.728372871
diff52 0.288867147 0.526190089 0.728372871 1.000000000
Initial Parameter Estimates for EM
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -3.244186 -4.662791 -8.325581 -15.127907
COV diff4 57.127907 47.389193 42.143092 36.780164
COV diff12 47.389193 101.920246 90.275787 85.749521
COV diff24 42.143092 90.275787 141.986867 134.381395
COV diff52 36.780164 85.749521 134.381395 239.806977
EM (MLE) Iteration History
_Iteration_ -2 Log L diff4 diff12 diff24 diff52
0 2290.659556 -3.244186 -4.662791 -8.325581 -15.127907
1 2273.220666 -3.475149 -5.801777 -9.010677 -16.061625
2 2273.150112 -3.472286 -5.849916 -9.018991 -16.099338
3 2273.148152 -3.472508 -5.852453 -9.016772 -16.098936
4 2273.147922 -3.472587 -5.852546 -9.016004 -16.097430
5 2273.147877 -3.472606 -5.852533 -9.015752 -16.096626
6 2273.147867 -3.472611 -5.852524 -9.015655 -16.096251
7 2273.147865 -3.472613 -5.852520 -9.015614 -16.096082
8 2273.147864 -3.472614 -5.852518 -9.015595 -16.096006
9 2273.147864 -3.472614 -5.852517 -9.015586 -16.095971
EM with CC initial values
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 79
treat=2
The MI Procedure
EM (MLE) Parameter Estimates
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -3.472614 -5.852517 -9.015586 -16.095971
COV diff4 77.341315 65.693471 63.603097 53.188213
COV diff12 65.693471 139.657797 126.203835 116.797829
COV diff24 63.603097 126.203835 194.336656 181.986036
COV diff52 53.188213 116.797829 181.986036 283.062059
EM (Posterior Mode) Estimates
_TYPE_ _NAME_ diff4 diff12 diff24 diff52
MEAN -3.472576 -5.852548 -9.016530 -16.095482
COV diff4 74.112751 62.983750 60.970724 51.001727
COV diff12 62.983750 133.719788 120.846896 111.863598
COV diff24 60.970724 120.846896 185.801331 174.099740
COV diff52 51.001727 111.863598 174.099740 269.756851
2. GEE and GLMM analyses
CC - GEE
The GENMOD Procedure
Model Information
Data Set M.ARMDCC
Distribution Binomial
Link Function Logit
Dependent Variable bindif
Number of Observations Read 752
Number of Observations Used 752
Number of Events 218
Number of Trials 752
Class Level Information
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 188 2 4 6 7 8 9 12 13 14 15 16 17 18 19 20 22 23 24 25
26 27 29 33 34 35 36 39 40 42 43 44 45 46 49 51 52
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 80
53 54 55 57 58 59 60 61 62 63 64 65 66 67 68 69 70
71 72 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88
89 92 93 94 95 96 99 102 103 104 105 106 107 108
...
Response Profile
Ordered Total
Value bindif Frequency
1 0 218
2 1 534
PROC GENMOD is modeling the probability that bindif=’0’. One way to change this to model the
probability that bindif=’1’ is to specify the DESCENDING option in the PROC statement.
Parameter Information
Parameter Effect time treat
Prm1 Intercept
Prm2 time 1
Prm3 time 2
Prm4 time 3
Prm5 time 4
Prm6 time*treat 1 1
Prm7 time*treat 1 2
Prm8 time*treat 2 1
Prm9 time*treat 2 2
Prm10 time*treat 3 1
Prm11 time*treat 3 2
Prm12 time*treat 4 1
Prm13 time*treat 4 2
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 744 885.5608 1.1903
Scaled Deviance 744 885.5608 1.1903
Pearson Chi-Square 744 752.0000 1.0108
Scaled Pearson X2 744 752.0000 1.0108
Log Likelihood -442.7804
Algorithm converged.
Analysis Of Initial Parameter Estimates
Standard Wald 95% Confidence Chi-
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 81
Parameter DF Estimate Error Limits Square Pr > ChiSq
Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
time 1 1 -1.0076 0.2436 -1.4851 -0.5302 17.11 <.0001
time 2 1 -0.8920 0.2375 -1.3574 -0.4266 14.11 0.0002
time 3 1 -1.1299 0.2510 -1.6218 -0.6379 20.26 <.0001
time 4 1 -1.6376 0.2921 -2.2101 -1.0651 31.43 <.0001
time*treat 1 1 1 0.4015 0.3198 -0.2253 1.0283 1.58 0.2093
time*treat 1 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 1 0.4947 0.3117 -0.1163 1.1057 2.52 0.1125
time*treat 2 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 1 0.4805 0.3263 -0.1591 1.1201 2.17 0.1409
time*treat 3 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 1 0.4037 0.3761 -0.3335 1.1408 1.15 0.2832
time*treat 4 2 0 0.0000 0.0000 0.0000 0.0000 . .
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
The GENMOD Procedure
Lagrange Multiplier Statistics
Parameter Chi-Square Pr > ChiSq
Intercept . .
GEE Model Information
Correlation Structure Exchangeable
Within-Subject Effect time (4 levels)
Subject Effect subject (188 levels)
Number of Clusters 188
Correlation Matrix Dimension 4
Maximum Cluster Size 4
Minimum Cluster Size 4
Algorithm converged.
Exchangeable Working
Correlation
Correlation 0.3878480087
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 82
Intercept 0.0000 0.0000 0.0000 0.0000 . .
time 1 -1.0076 0.2436 -1.4851 -0.5302 -4.14 <.0001
time 2 -0.8920 0.2375 -1.3574 -0.4266 -3.76 0.0002
time 3 -1.1299 0.2510 -1.6218 -0.6379 -4.50 <.0001
time 4 -1.6376 0.2921 -2.2101 -1.0651 -5.61 <.0001
time*treat 1 1 0.4015 0.3198 -0.2253 1.0283 1.26 0.2093
time*treat 1 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 0.4947 0.3117 -0.1163 1.1057 1.59 0.1125
time*treat 2 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 0.4805 0.3263 -0.1591 1.1201 1.47 0.1409
time*treat 3 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 0.4037 0.3761 -0.3335 1.1408 1.07 0.2832
time*treat 4 2 0.0000 0.0000 0.0000 0.0000 . .
The GENMOD Procedure
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.0000 0.0000 0.0000 0.0000 . .
time 1 -1.0076 0.2436 -1.4851 -0.5302 -4.14 <.0001
time 2 -0.8920 0.2375 -1.3574 -0.4266 -3.76 0.0002
time 3 -1.1299 0.2510 -1.6218 -0.6379 -4.50 <.0001
time 4 -1.6376 0.2921 -2.2101 -1.0651 -5.61 <.0001
time*treat 1 1 0.4015 0.3198 -0.2253 1.0283 1.26 0.2093
time*treat 1 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 0.4947 0.3117 -0.1163 1.1057 1.59 0.1125
time*treat 2 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 0.4805 0.3263 -0.1591 1.1201 1.47 0.1409
time*treat 3 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 0.4037 0.3761 -0.3335 1.1408 1.07 0.2832
time*treat 4 2 0.0000 0.0000 0.0000 0.0000 . .
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
CC - GEE - linearized version 20:20 Monday, May 16, 2005 179
The GLIMMIX Procedure
Model Information
Data Set M.ARMDCC
Response Variable bindif
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By subject
Estimation Technique Residual PL
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 83
Degrees of Freedom Method Between-Within
Class Level Information
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 188 2 4 6 7 8 9 12 13 14 15 16 17 18 19 20 22 23
24 25 26 27 29 33 34 35 36 39 40 42 43 44 45
46 49 51 52 53 54 55 57 58 59 60 61 62 63 64
65 66 67 68 69 70 71 72 74 75 76 77 78 79 80
81 82 83 84 85 86 87 88 89 92 93 94 95 96 99
102 103 104 105 106 107 108 109 110 111 112
113 115 116 117 118 119 120 121 123 124 125
126 127 128 129 130 132 134 135 137 138 139
140 141 142 143 145 146 149 151 152 153 154
155 156 157 158 159 160 161 162 164 165 166
168 169 170 171 172 173 175 176 178 179 180
181 182 183 184 185 187 188 190 192 193 194
195 199 202 203 205 206 208 209 210 211 212
214 215 217 218 220 221 222 223 224 225 226
227 228 229 232 233 234 235 236 237 238 239
240
Number of Observations Read 752
Number of Observations Used 752
Response Profile
Ordered Total
Value bindif Frequency
1 0 218
2 1 534
The GLIMMIX procedure is modeling the probability that bindif=’0’.
The GLIMMIX Procedure
Dimensions
R-side Cov. Parameters 2
Columns in X 12
Columns in Z per Subject 0
Subjects (Blocks in V) 188
Max Obs per Subject 4
Optimization Information
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 84
Optimization Technique Newton-Raphson
Parameters in Optimization 1
Lower Boundaries 0
Upper Boundaries 0
Fixed Effects Profiled
Residual Variance Profiled
Starting From Data
Iteration History
Objective Max
Iteration Restarts Subiterations Function Change Gradient
0 0 2 3290.4920765 0.28577085 1.98E-8
1 0 1 3228.4753932 0.00736502 0.000054
2 0 1 3229.9762787 0.00002566 9.344E-8
3 0 0 3229.9774035 0.00000000 3.758E-6
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Res Log Pseudo-Likelihood 3229.98
Generalized Chi-Square 459.16
Gener. Chi-Square / DF 0.62
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
CS subject 0.3936 0.05756
Residual 0.6172 0.03695
Solutions for Fixed Effects
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -1.0076 0.2449 556 -4.11 <.0001
time 2 -0.8920 0.2387 556 -3.74 0.0002
time 3 -1.1299 0.2524 556 -4.48 <.0001
time 4 -1.6376 0.2937 556 -5.58 <.0001
time*treat 1 1 0.4015 0.3215 556 1.25 0.2123
time*treat 1 2 0 . . . .
time*treat 2 1 0.4947 0.3134 556 1.58 0.1150
time*treat 2 2 0 . . . .
time*treat 3 1 0.4805 0.3281 556 1.46 0.1436
time*treat 3 2 0 . . . .
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 85
time*treat 4 1 0.4037 0.3781 556 1.07 0.2862
time*treat 4 2 0 . . . .
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 556 16.82 <.0001
time*treat 4 556 0.89 0.4687
CC - GEE - linearized version - empirical
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
CS subject 0.3936 0.05756
Residual 0.6172 0.03695
Solutions for Fixed Effects
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -1.0076 0.2436 556 -4.14 <.0001
time 2 -0.8920 0.2375 556 -3.76 0.0002
time 3 -1.1299 0.2510 556 -4.50 <.0001
time 4 -1.6376 0.2921 556 -5.61 <.0001
time*treat 1 1 0.4015 0.3198 556 1.26 0.2098
time*treat 1 2 0 . . . .
time*treat 2 1 0.4947 0.3117 556 1.59 0.1131
time*treat 2 2 0 . . . .
time*treat 3 1 0.4805 0.3263 556 1.47 0.1415
time*treat 3 2 0 . . . .
time*treat 4 1 0.4037 0.3761 556 1.07 0.2836
time*treat 4 2 0 . . . .
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 556 18.06 <.0001
time*treat 4 556 0.87 0.4797
LOCF - GEE
The GENMOD Procedure
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 86
Model Information
Data Set M.ARMDLOCF
Distribution Binomial
Link Function Logit
Dependent Variable LOCF
Number of Observations Read 960
Number of Observations Used 933
Number of Events 273
Number of Trials 933
Missing Values 27
Class Level Information
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 240 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71
72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87
...
Response Profile
Ordered Total
Value LOCF Frequency
1 0 273
2 1 660
PROC GENMOD is modeling the probability that LOCF=’0’. One way to change this to model the
probability that LOCF=’1’ is to specify the DESCENDING option in the PROC statement.
Parameter Information
Parameter Effect time treat
Prm1 Intercept
Prm2 time 1
Prm3 time 2
Prm4 time 3
Prm5 time 4
Prm6 time*treat 1 1
LOCF - GEE
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 87
The GENMOD Procedure
Parameter Information
Parameter Effect time treat
Prm7 time*treat 1 2
Prm8 time*treat 2 1
Prm9 time*treat 2 2
Prm10 time*treat 3 1
Prm11 time*treat 3 2
Prm12 time*treat 4 1
Prm13 time*treat 4 2
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 925 1108.6193 1.1985
Scaled Deviance 925 1108.6193 1.1985
Pearson Chi-Square 925 932.9997 1.0086
Scaled Pearson X2 925 932.9997 1.0086
Log Likelihood -554.3096
Algorithm converged.
Analysis Of Initial Parameter Estimates
Standard Wald 95% Confidence Chi-
Parameter DF Estimate Error Limits Square Pr > ChiSq
Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
time 1 1 -0.8557 0.2047 -1.2569 -0.4544 17.47 <.0001
time 2 1 -0.9651 0.2077 -1.3722 -0.5579 21.58 <.0001
time 3 1 -1.0531 0.2120 -1.4687 -0.6376 24.67 <.0001
time 4 1 -1.5094 0.2411 -1.9820 -1.0367 39.18 <.0001
time*treat 1 1 1 0.2007 0.2827 -0.3533 0.7548 0.50 0.4776
time*treat 1 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 1 0.5525 0.2802 0.0034 1.1017 3.89 0.0486
time*treat 2 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 1 0.4229 0.2869 -0.1395 0.9853 2.17 0.1405
time*treat 3 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 1 0.3417 0.3240 -0.2933 0.9768 1.11 0.2915
time*treat 4 2 0 0.0000 0.0000 0.0000 0.0000 . .
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
Lagrange Multiplier Statistics
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 88
Parameter Chi-Square Pr > ChiSq
Intercept . .
GEE Model Information
Correlation Structure Exchangeable
Within-Subject Effect time (4 levels)
Subject Effect subject (240 levels)
Number of Clusters 240
Clusters With Missing Values 9
Correlation Matrix Dimension 4
Maximum Cluster Size 4
Minimum Cluster Size 0
Algorithm converged.
Exchangeable Working
Correlation
Correlation 0.4373108915
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.0000 0.0000 0.0000 0.0000 . .
time 1 -0.8707 0.2055 -1.2735 -0.4678 -4.24 <.0001
time 2 -0.9651 0.2077 -1.3722 -0.5579 -4.65 <.0001
time 3 -1.0531 0.2120 -1.4687 -0.6376 -4.97 <.0001
time 4 -1.5094 0.2411 -1.9820 -1.0367 -6.26 <.0001
time*treat 1 1 0.2243 0.2827 -0.3298 0.7785 0.79 0.4275
time*treat 1 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 0.5525 0.2802 0.0034 1.1017 1.97 0.0486
time*treat 2 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 0.4229 0.2869 -0.1395 0.9853 1.47 0.1405
time*treat 3 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 0.3417 0.3240 -0.2933 0.9768 1.05 0.2915
time*treat 4 2 0.0000 0.0000 0.0000 0.0000 . .
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.0000 0.0000 0.0000 0.0000 . .
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 89
time 1 -0.8707 0.2048 -1.2721 -0.4693 -4.25 <.0001
time 2 -0.9651 0.2077 -1.3722 -0.5579 -4.65 <.0001
time 3 -1.0531 0.2120 -1.4687 -0.6376 -4.97 <.0001
time 4 -1.5094 0.2411 -1.9820 -1.0367 -6.26 <.0001
time*treat 1 1 0.2243 0.2824 -0.3291 0.7778 0.79 0.4269
time*treat 1 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 0.5525 0.2802 0.0034 1.1017 1.97 0.0486
time*treat 2 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 0.4229 0.2869 -0.1395 0.9853 1.47 0.1405
time*treat 3 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 0.3417 0.3240 -0.2933 0.9768 1.05 0.2915
time*treat 4 2 0.0000 0.0000 0.0000 0.0000 . .
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
LOCF - GEE - linearized version
The GLIMMIX Procedure
Model Information
Data Set M.ARMDLOCF
Response Variable LOCF
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By subject
Estimation Technique Residual PL
Degrees of Freedom Method Between-Within
Class Level Information
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 234 1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19
20 22 23 24 25 26 27 29 30 31 32 33 34 35 36
37 38 39 40 41 42 43 44 45 46 47 49 50 51 52
53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
68 69 70 71 72 73 74 75 76 77 78 79 80 81 82
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
98 99 100 101 102 103 104 105 106 107 108 109
110 111 112 113 114 115 116 117 118 119 120
121 122 123 124 125 126 127 128 129 130 131
132 133 134 135 136 137 138 139 140 141 142
143 145 146 147 148 149 150 151 152 153 154
155 156 157 158 159 160 161 162 163 164 165
166 167 168 169 170 171 172 173 174 175 176
177 178 179 180 181 182 183 184 185 186 187
188 190 191 192 193 194 195 196 197 198 199
200 201 202 203 204 205 206 207 208 209 210
211 212 213 214 215 216 217 218 219 220 221
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 90
222 223 224 225 226 227 228 229 230 231 232
233 234 235 236 237 238 239 240
Number of Observations Read 960
Number of Observations Used 933
Response Profile
Ordered Total
Value LOCF Frequency
1 0 273
The GLIMMIX procedure is modeling the probability that LOCF=’0’.
Response Profile
Ordered Total
Value LOCF Frequency
2 1 660
The GLIMMIX procedure is modeling the probability that LOCF=’0’.
Dimensions
R-side Cov. Parameters 2
Columns in X 12
Columns in Z per Subject 0
Subjects (Blocks in V) 234
Max Obs per Subject 4
Optimization Information
Optimization Technique Newton-Raphson
Parameters in Optimization 1
Lower Boundaries 0
Upper Boundaries 0
Fixed Effects Profiled
Residual Variance Profiled
Starting From Data
Iteration History
Objective Max
Iteration Restarts Subiterations Function Change Gradient
0 0 2 4033.7303417 0.22962606 7.948E-7
1 0 1 3949.5889542 0.00826676 7.989E-6
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 91
2 0 1 3951.5825139 0.00000864 8.041E-9
3 0 0 3951.5841239 0.00000002 2.353E-6
4 0 0 3951.5841245 0.00000000 2.337E-6
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Res Log Pseudo-Likelihood 3951.58
Generalized Chi-Square 524.61
Gener. Chi-Square / DF 0.57
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
CS subject 0.4415 0.05472
Residual 0.5672 0.03046
Solutions for Fixed Effects
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -0.8707 0.2057 691 -4.23 <.0001
time 2 -0.9651 0.2086 691 -4.63 <.0001
time 3 -1.0531 0.2130 691 -4.95 <.0001
time 4 -1.5094 0.2422 691 -6.23 <.0001
time*treat 1 1 0.2243 0.2836 691 0.79 0.4292
time*treat 1 2 0 . . . .
time*treat 2 1 0.5525 0.2814 691 1.96 0.0500
time*treat 2 2 0 . . . .
time*treat 3 1 0.4229 0.2882 691 1.47 0.1427
time*treat 3 2 0 . . . .
time*treat 4 1 0.3417 0.3254 691 1.05 0.2940
time*treat 4 2 0 . . . .
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 691 18.92 <.0001
time*treat 4 691 1.10 0.3552
LOCF - GEE - linearized version - empirical
Covariance Parameter Estimates
Standard
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 92
Cov Parm Subject Estimate Error
CS subject 0.4415 0.05472
Residual 0.5672 0.03046
Solutions for Fixed Effects
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -0.8707 0.2055 691 -4.24 <.0001
time 2 -0.9651 0.2077 691 -4.65 <.0001
time 3 -1.0531 0.2120 691 -4.97 <.0001
time 4 -1.5094 0.2411 691 -6.26 <.0001
time*treat 1 1 0.2243 0.2827 691 0.79 0.4278
time*treat 1 2 0 . . . .
time*treat 2 1 0.5525 0.2802 691 1.97 0.0490
time*treat 2 2 0 . . . .
time*treat 3 1 0.4229 0.2869 691 1.47 0.1410
time*treat 3 2 0 . . . .
time*treat 4 1 0.3417 0.3240 691 1.05 0.2919
time*treat 4 2 0 . . . .
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 691 20.10 <.0001
time*treat 4 691 1.01 0.4028
data as is - GEE
The GENMOD Procedure
Model Information
Data Set M.ARMDWGEE
Distribution Binomial
Link Function Logit
Dependent Variable bindif
Number of Observations Read 960
Number of Observations Used 867
Number of Events 252
Number of Trials 867
Missing Values 93
Class Level Information
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 93
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 240 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71
72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87
...
Response Profile
Ordered Total
Value bindif Frequency
1 0 252
2 1 615
PROC GENMOD is modeling the probability that bindif=’0’. One way to change this to model the
probability that bindif=’1’ is to specify the DESCENDING option in the PROC statement.
Parameter Information
Parameter Effect time treat
Prm1 Intercept
Prm2 time 1
Prm3 time 2
Prm4 time 3
Prm5 time 4
Prm6 time*treat 1 1
Prm7 time*treat 1 2
Prm8 time*treat 2 1
Prm9 time*treat 2 2
Prm10 time*treat 3 1
Prm11 time*treat 3 2
Prm12 time*treat 4 1
Prm13 time*treat 4 2
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 859 1022.5545 1.1904
Scaled Deviance 859 1022.5545 1.1904
Pearson Chi-Square 859 867.0000 1.0093
Scaled Pearson X2 859 867.0000 1.0093
Log Likelihood -511.2773
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 94
Algorithm converged.
Analysis Of Initial Parameter Estimates
Standard Wald 95% Confidence Chi-
Parameter DF Estimate Error Limits Square Pr > ChiSq
Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
time 1 1 -0.8557 0.2047 -1.2569 -0.4544 17.47 <.0001
time 2 1 -1.0272 0.2164 -1.4513 -0.6030 22.53 <.0001
time 3 1 -1.0726 0.2272 -1.5179 -0.6273 22.29 <.0001
time 4 1 -1.6917 0.2908 -2.2617 -1.1216 33.83 <.0001
time*treat 1 1 1 0.2007 0.2827 -0.3533 0.7548 0.50 0.4776
time*treat 1 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 1 0.6288 0.2870 0.0662 1.1914 4.80 0.0285
time*treat 2 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 1 0.4457 0.3016 -0.1454 1.0369 2.18 0.1394
time*treat 3 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 1 0.4205 0.3745 -0.3136 1.1545 1.26 0.2616
time*treat 4 2 0 0.0000 0.0000 0.0000 0.0000 . .
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
Lagrange Multiplier Statistics
Parameter Chi-Square Pr > ChiSq
Intercept . .
GEE Model Information
Correlation Structure Exchangeable
Within-Subject Effect time (4 levels)
Subject Effect subject (240 levels)
Number of Clusters 240
Clusters With Missing Values 52
Correlation Matrix Dimension 4
Maximum Cluster Size 4
Minimum Cluster Size 0
Algorithm converged.
Exchangeable Working
Correlation
Correlation 0.3885277558
Analysis Of GEE Parameter Estimates
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 95
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.0000 0.0000 0.0000 0.0000 . .
time 1 -0.8669 0.2054 -1.2695 -0.4644 -4.22 <.0001
time 2 -1.0116 0.2145 -1.4320 -0.5911 -4.72 <.0001
time 3 -1.0703 0.2232 -1.5077 -0.6329 -4.80 <.0001
time 4 -1.7091 0.2899 -2.2773 -1.1408 -5.89 <.0001
time*treat 1 1 0.2201 0.2827 -0.3339 0.7741 0.78 0.4361
time*treat 1 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 0.6083 0.2856 0.0486 1.1680 2.13 0.0332
time*treat 2 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 0.4404 0.2981 -0.1438 1.0247 1.48 0.1396
time*treat 3 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 0.4359 0.3726 -0.2944 1.1662 1.17 0.2421
time*treat 4 2 0.0000 0.0000 0.0000 0.0000 . .
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.0000 0.0000 0.0000 0.0000 . .
time 1 -0.8669 0.2048 -1.2684 -0.4655 -4.23 <.0001
time 2 -1.0116 0.2147 -1.4324 -0.5908 -4.71 <.0001
time 3 -1.0703 0.2243 -1.5100 -0.6306 -4.77 <.0001
time 4 -1.7091 0.2850 -2.2677 -1.1505 -6.00 <.0001
time*treat 1 1 0.2201 0.2824 -0.3334 0.7737 0.78 0.4357
time*treat 1 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 0.6083 0.2857 0.0483 1.1684 2.13 0.0333
time*treat 2 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 0.4404 0.2988 -0.1452 1.0260 1.47 0.1404
time*treat 3 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 0.4359 0.3681 -0.2856 1.1573 1.18 0.2364
time*treat 4 2 0.0000 0.0000 0.0000 0.0000 . .
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
data as is - GEE - linearized version
Model Information
Data Set M.ARMDWGEE
Response Variable bindif
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By subject
Estimation Technique Residual PL
Degrees of Freedom Method Between-Within
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 96
Class Level Information
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 234 1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19
20 22 23 24 25 26 27 29 30 31 32 33 34 35 36
37 38 39 40 41 42 43 44 45 46 47 49 50 51 52
53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
68 69 70 71 72 73 74 75 76 77 78 79 80 81 82
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
98 99 100 101 102 103 104 105 106 107 108 109
110 111 112 113 114 115 116 117 118 119 120
121 122 123 124 125 126 127 128 129 130 131
132 133 134 135 136 137 138 139 140 141 142
143 145 146 147 148 149 150 151 152 153 154
155 156 157 158 159 160 161 162 163 164 165
166 167 168 169 170 171 172 173 174 175 176
177 178 179 180 181 182 183 184 185 186 187
188 190 191 192 193 194 195 196 197 198 199
200 201 202 203 204 205 206 207 208 209 210
211 212 213 214 215 216 217 218 219 220 221
222 223 224 225 226 227 228 229 230 231 232
233 234 235 236 237 238 239 240
Number of Observations Read 960
Number of Observations Used 867
Response Profile
Ordered Total
Value bindif Frequency
1 0 252
The GLIMMIX procedure is modeling the probability that bindif=’0’.
data as is - GEE - linearized version
The GLIMMIX Procedure
Response Profile
Ordered Total
Value bindif Frequency
2 1 615
The GLIMMIX procedure is modeling the probability that bindif=’0’.
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 97
Dimensions
R-side Cov. Parameters 2
Columns in X 12
Columns in Z per Subject 0
Subjects (Blocks in V) 234
Max Obs per Subject 4
Optimization Information
Optimization Technique Newton-Raphson
Parameters in Optimization 1
Lower Boundaries 0
Upper Boundaries 0
Fixed Effects Profiled
Residual Variance Profiled
Starting From Data
Iteration History
Objective Max
Iteration Restarts Subiterations Function Change Gradient
0 0 2 3798.0526759 0.31166692 2.144E-6
1 0 1 3728.7297728 0.00742859 0.000041
2 0 1 3730.3894543 0.00004304 4.076E-8
3 0 1 3730.3935466 . 4.43E-11
4 0 7 3730.3935466 2.00000000 2.249E-7
5 0 0 3730.3935419 0.00000000 6.846E-7
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Res Log Pseudo-Likelihood 3730.39
Generalized Chi-Square 530.72
Gener. Chi-Square / DF 0.62
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
CS subject 0.3916 0.05303
Residual 0.6178 0.03483
Solutions for Fixed Effects
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 98
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -0.8669 0.2058 625 -4.21 <.0001
time 2 -1.0116 0.2157 625 -4.69 <.0001
time 3 -1.0703 0.2254 625 -4.75 <.0001
time 4 -1.7091 0.2864 625 -5.97 <.0001
time*treat 1 1 0.2201 0.2838 625 0.78 0.4382
time*treat 1 2 0 . . . .
time*treat 2 1 0.6083 0.2871 625 2.12 0.0345
time*treat 2 2 0 . . . .
time*treat 3 1 0.4404 0.3002 625 1.47 0.1428
time*treat 3 2 0 . . . .
time*treat 4 1 0.4358 0.3698 625 1.18 0.2390
time*treat 4 2 0 . . . .
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 625 19.58 <.0001
time*treat 4 625 1.29 0.2712
data as is - GEE - linearized version - empirical
The GLIMMIX Procedure
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
CS subject 0.3916 0.05303
Residual 0.6178 0.03483
Solutions for Fixed Effects
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -0.8669 0.2054 625 -4.22 <.0001
time 2 -1.0116 0.2145 625 -4.72 <.0001
time 3 -1.0703 0.2232 625 -4.80 <.0001
time 4 -1.7091 0.2899 625 -5.89 <.0001
time*treat 1 1 0.2201 0.2827 625 0.78 0.4364
time*treat 1 2 0 . . . .
time*treat 2 1 0.6083 0.2856 625 2.13 0.0335
time*treat 2 2 0 . . . .
time*treat 3 1 0.4404 0.2981 625 1.48 0.1401
time*treat 3 2 0 . . . .
time*treat 4 1 0.4358 0.3726 625 1.17 0.2426
time*treat 4 2 0 . . . .
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 99
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 625 20.66 <.0001
time*treat 4 625 1.21 0.3059
data as is - WGEE
The GENMOD Procedure
Model Information
Data Set M.ARMDWGEE
Distribution Binomial
Link Function Logit
Dependent Variable bindif
Scale Weight Variable WI
Number of Observations Read 960
Number of Observations Used 846
Sum of Weights 2249.749
Number of Events 246
Number of Trials 846
Missing Values 114
Class Level Information
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 240 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71
72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87
...
Response Profile
Ordered Total
Value bindif Frequency
1 0 733.2344
2 1 1516.515
PROC GENMOD is modeling the probability that bindif=’0’. One way to change this to model the
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 100
probability that bindif=’1’ is to specify the DESCENDING option in the PROC statement.
Parameter Information
Parameter Effect time treat
Prm1 Intercept
Prm2 time 1
Prm3 time 2
Prm4 time 3
Prm5 time 4
Prm6 time*treat 1 1
Prm7 time*treat 1 2
Prm8 time*treat 2 1
Prm9 time*treat 2 2
Prm10 time*treat 3 1
Prm11 time*treat 3 2
Prm12 time*treat 4 1
Prm13 time*treat 4 2
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 838 2665.1553 3.1804
Scaled Deviance 838 2665.1553 3.1804
Pearson Chi-Square 838 2249.7494 2.6847
Scaled Pearson X2 838 2249.7494 2.6847
Log Likelihood -1332.5777
Algorithm converged.
Analysis Of Initial Parameter Estimates
Standard Wald 95% Confidence Chi-
Parameter DF Estimate Error Limits Square Pr > ChiSq
Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
time 1 1 -0.9781 0.1034 -1.1809 -0.7754 89.44 <.0001
time 2 1 -1.7889 0.1569 -2.0963 -1.4814 130.05 <.0001
time 3 1 -0.9542 0.1528 -1.2538 -0.6547 38.98 <.0001
time 4 1 -1.5243 0.2490 -2.0123 -1.0363 37.49 <.0001
time*treat 1 1 1 0.8013 0.1457 0.5158 1.0869 30.25 <.0001
time*treat 1 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 1 1.8954 0.1883 1.5264 2.2644 101.36 <.0001
time*treat 2 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 1 0.2103 0.2031 -0.1877 0.6083 1.07 0.3004
time*treat 3 2 0 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 1 0.2995 0.3337 -0.3545 0.9535 0.81 0.3694
time*treat 4 2 0 0.0000 0.0000 0.0000 0.0000 . .
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 101
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
Lagrange Multiplier Statistics
Parameter Chi-Square Pr > ChiSq
Intercept . .
GEE Model Information
Correlation Structure Exchangeable
Within-Subject Effect time (4 levels)
Subject Effect subject (240 levels)
Number of Clusters 240
Clusters With Missing Values 52
Correlation Matrix Dimension 4
Maximum Cluster Size 4
Minimum Cluster Size 0
Algorithm converged.
Exchangeable Working
Correlation
Correlation 0.3277731297
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.0000 0.0000 0.0000 0.0000 . .
time 1 -0.9781 0.4407 -1.8419 -0.1144 -2.22 0.0265
time 2 -1.7822 0.3751 -2.5174 -1.0470 -4.75 <.0001
time 3 -1.1125 0.3334 -1.7659 -0.4591 -3.34 0.0008
time 4 -1.7189 0.3913 -2.4859 -0.9519 -4.39 <.0001
time*treat 1 1 0.8013 0.6696 -0.5111 2.1138 1.20 0.2314
time*treat 1 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 1.8679 0.6103 0.6717 3.0640 3.06 0.0022
time*treat 2 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 0.7337 0.5322 -0.3094 1.7769 1.38 0.1680
time*treat 3 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 0.7383 0.5166 -0.2743 1.7508 1.43 0.1530
time*treat 4 2 0.0000 0.0000 0.0000 0.0000 . .
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 102
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.0000 0.0000 0.0000 0.0000 . .
time 1 -0.9781 0.1034 -1.1809 -0.7754 -9.46 <.0001
time 2 -1.7822 0.1540 -2.0840 -1.4804 -11.57 <.0001
time 3 -1.1125 0.1524 -1.4111 -0.8139 -7.30 <.0001
time 4 -1.7189 0.2472 -2.2034 -1.2344 -6.95 <.0001
time*treat 1 1 0.8013 0.1457 0.5158 1.0869 5.50 <.0001
time*treat 1 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 2 1 1.8679 0.1857 1.5038 2.2319 10.06 <.0001
time*treat 2 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 3 1 0.7337 0.1963 0.3489 1.1185 3.74 0.0002
time*treat 3 2 0.0000 0.0000 0.0000 0.0000 . .
time*treat 4 1 0.7383 0.3148 0.1213 1.3552 2.35 0.0190
time*treat 4 2 0.0000 0.0000 0.0000 0.0000 . .
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
data as is - WGEE - linearized version
The GLIMMIX Procedure
Model Information
Data Set M.ARMDWGEE
Response Variable bindif
Response Distribution Binary
Link Function Logit
Variance Function Default
Weight Variable WI
Variance Matrix Blocked By subject
Estimation Technique Residual PL
Degrees of Freedom Method Between-Within
Class Level Information
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 234 1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19
20 22 23 24 25 26 27 29 30 31 32 33 34 35 36
37 38 39 40 41 42 43 44 45 46 47 49 50 51 52
53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
68 69 70 71 72 73 74 75 76 77 78 79 80 81 82
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
98 99 100 101 102 103 104 105 106 107 108 109
110 111 112 113 114 115 116 117 118 119 120
121 122 123 124 125 126 127 128 129 130 131
132 133 134 135 136 137 138 139 140 141 142
143 145 146 147 148 149 150 151 152 153 154
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 103
155 156 157 158 159 160 161 162 163 164 165
166 167 168 169 170 171 172 173 174 175 176
177 178 179 180 181 182 183 184 185 186 187
188 190 191 192 193 194 195 196 197 198 199
200 201 202 203 204 205 206 207 208 209 210
211 212 213 214 215 216 217 218 219 220 221
222 223 224 225 226 227 228 229 230 231 232
233 234 235 236 237 238 239 240
Number of Observations Read 960
Number of Observations Used 846
Response Profile
Ordered Total
Value bindif Frequency
1 0 246
2 1 600
The GLIMMIX procedure is modeling the probability that bindif=’0’.
Dimensions
R-side Cov. Parameters 2
Columns in X 12
Columns in Z per Subject 0
Subjects (Blocks in V) 234
Max Obs per Subject 4
Optimization Information
Optimization Technique Newton-Raphson
Parameters in Optimization 1
Lower Boundaries 0
Upper Boundaries 0
Fixed Effects Profiled
Residual Variance Profiled
Starting From Data
Iteration History
Objective Max
Iteration Restarts Subiterations Function Change Gradient
0 0 3 4097.6696637 0.15208155 0.000032
1 0 2 4077.0629889 0.00967492 3.701E-7
2 0 1 4078.8642714 0.00056760 2.889E-6
3 0 1 4078.7916245 0.00003595 1.162E-8
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 104
4 0 1 4078.7960437 . 6.67E-11
5 0 8 4078.7960437 2.00000000 5.777E-9
6 0 1 4078.7954956 0.00000043 2.34E-12
7 0 0 4078.7955404 0.00000003 1.037E-6
8 0 0 4078.795535 0.00000001 8.981E-7
Convergence criterion (PCONV=1.11022E-8) satisfied.
data as is - WGEE - linearized version
The GLIMMIX Procedure
Fit Statistics
-2 Res Log Pseudo-Likelihood 4078.80
Generalized Chi-Square 1084.86
Gener. Chi-Square / DF 1.29
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
CS subject 1.8446 0.2339
Residual 1.2946 0.07679
Solutions for Fixed Effects
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -0.9781 0.1832 604 -5.34 <.0001
time 2 -1.7769 0.2622 604 -6.78 <.0001
time 3 -1.1893 0.2532 604 -4.70 <.0001
time 4 -1.8112 0.3938 604 -4.60 <.0001
time*treat 1 1 0.8013 0.2581 604 3.10 0.0020
time*treat 1 2 0 . . . .
time*treat 2 1 1.8460 0.3199 604 5.77 <.0001
time*treat 2 2 0 . . . .
time*treat 3 1 0.9829 0.3265 604 3.01 0.0027
time*treat 3 2 0 . . . .
time*treat 4 1 0.9664 0.4923 604 1.96 0.0501
time*treat 4 2 0 . . . .
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 604 10.98 <.0001
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 105
time*treat 4 604 8.36 <.0001
data as is - WGEE - linearized version - empirical
The GLIMMIX Procedure
Model Information
Data Set M.ARMDWGEE
Response Variable bindif
Response Distribution Binary
Link Function Logit
Variance Function Default
Weight Variable WI
Variance Matrix Blocked By subject
Estimation Technique Residual PL
Degrees of Freedom Method Between-Within
Fixed Effects SE Adjustment Sandwich - Classical
Class Level Information
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 234 1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19
20 22 23 24 25 26 27 29 30 31 32 33 34 35 36
37 38 39 40 41 42 43 44 45 46 47 49 50 51 52
53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
68 69 70 71 72 73 74 75 76 77 78 79 80 81 82
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
98 99 100 101 102 103 104 105 106 107 108 109
110 111 112 113 114 115 116 117 118 119 120
121 122 123 124 125 126 127 128 129 130 131
132 133 134 135 136 137 138 139 140 141 142
143 145 146 147 148 149 150 151 152 153 154
155 156 157 158 159 160 161 162 163 164 165
166 167 168 169 170 171 172 173 174 175 176
177 178 179 180 181 182 183 184 185 186 187
188 190 191 192 193 194 195 196 197 198 199
200 201 202 203 204 205 206 207 208 209 210
211 212 213 214 215 216 217 218 219 220 221
222 223 224 225 226 227 228 229 230 231 232
233 234 235 236 237 238 239 240
Number of Observations Read 960
Number of Observations Used 846
Response Profile
Ordered Total
Value bindif Frequency
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 106
1 0 246
2 1 600
The GLIMMIX procedure is modeling the probability that bindif=’0’.
Dimensions
R-side Cov. Parameters 2
Columns in X 12
Columns in Z per Subject 0
Subjects (Blocks in V) 234
Max Obs per Subject 4
Optimization Information
Optimization Technique Newton-Raphson
Parameters in Optimization 1
Lower Boundaries 0
Upper Boundaries 0
Fixed Effects Profiled
Residual Variance Profiled
Starting From Data
Iteration History
Objective Max
Iteration Restarts Subiterations Function Change Gradient
0 0 3 4097.6696637 0.15208155 0.000032
1 0 2 4077.0629889 0.00967492 3.701E-7
2 0 1 4078.8642714 0.00056760 2.889E-6
3 0 1 4078.7916245 0.00003595 1.162E-8
4 0 1 4078.7960437 . 6.67E-11
5 0 8 4078.7960437 2.00000000 5.777E-9
6 0 1 4078.7954956 0.00000043 2.34E-12
7 0 0 4078.7955404 0.00000003 1.037E-6
8 0 0 4078.795535 0.00000001 8.981E-7
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Res Log Pseudo-Likelihood 4078.80
Generalized Chi-Square 1084.86
Gener. Chi-Square / DF 1.29
Covariance Parameter Estimates
Standard
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 107
Cov Parm Subject Estimate Error
CS subject 1.8446 0.2339
Residual 1.2946 0.07679
Solutions for Fixed Effects
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -0.9781 0.4407 604 -2.22 0.0268
time 2 -1.7769 0.4188 604 -4.24 <.0001
time 3 -1.1893 0.3775 604 -3.15 0.0017
time 4 -1.8112 0.4814 604 -3.76 0.0002
time*treat 1 1 0.8013 0.6696 604 1.20 0.2319
time*treat 1 2 0 . . . .
time*treat 2 1 1.8460 0.6367 604 2.90 0.0039
time*treat 2 2 0 . . . .
time*treat 3 1 0.9829 0.5969 604 1.65 0.1001
time*treat 3 2 0 . . . .
time*treat 4 1 0.9664 0.6454 604 1.50 0.1348
time*treat 4 2 0 . . . .
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 604 5.16 0.0004
time*treat 4 604 2.49 0.0422
CC - mixed - PQL
The GLIMMIX Procedure
Model Information
Data Set M.ARMDCC
Response Variable bindif
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By subject
Estimation Technique Residual PL
Degrees of Freedom Method Containment
Class Level Information
Class Levels Values
time 4 1 2 3 4
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 108
treat 2 1 2
subject 188 2 4 6 7 8 9 12 13 14 15 16 17 18 19 20 22 23
24 25 26 27 29 33 34 35 36 39 40 42 43 44 45
46 49 51 52 53 54 55 57 58 59 60 61 62 63 64
65 66 67 68 69 70 71 72 74 75 76 77 78 79 80
81 82 83 84 85 86 87 88 89 92 93 94 95 96 99
102 103 104 105 106 107 108 109 110 111 112
113 115 116 117 118 119 120 121 123 124 125
126 127 128 129 130 132 134 135 137 138 139
140 141 142 143 145 146 149 151 152 153 154
155 156 157 158 159 160 161 162 164 165 166
168 169 170 171 172 173 175 176 178 179 180
181 182 183 184 185 187 188 190 192 193 194
195 199 202 203 205 206 208 209 210 211 212
214 215 217 218 220 221 222 223 224 225 226
227 228 229 232 233 234 235 236 237 238 239
240
Number of Observations Read 752
Number of Observations Used 752
Response Profile
Ordered Total
Value bindif Frequency
1 0 218
2 1 534
The GLIMMIX procedure is modeling the probability that bindif=’0’.
The GLIMMIX Procedure
Dimensions
G-side Cov. Parameters 1
Columns in X 12
Columns in Z per Subject 1
Subjects (Blocks in V) 188
Max Obs per Subject 4
Optimization Information
Optimization Technique Newton-Raphson
Parameters in Optimization 1
Lower Boundaries 1
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 109
Iteration History
Objective Max
Iteration Restarts Subiterations Function Change Gradient
0 0 4 3373.5642704 0.32012192 4.854E-8
1 0 3 3451.2809298 0.10686186 4.923E-7
2 0 3 3479.5329722 0.03013256 2.85E-11
3 0 2 3486.3804256 0.00698688 8.052E-8
4 0 2 3487.882408 0.00151187 1.79E-10
5 0 1 3488.2026488 0.00032112 2.989E-6
6 0 1 3488.2704392 0.00006806 1.342E-7
7 0 1 3488.284796 0.00001439 6.003E-9
8 0 1 3488.2878318 0.00000304 2.68E-10
9 0 1 3488.2884735 0.00000064 1.21E-11
10 0 0 3488.2886091 0.00000000 3.619E-6
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Res Log Pseudo-Likelihood 3488.29
Generalized Chi-Square 497.38
Gener. Chi-Square / DF 0.67
The GLIMMIX Procedure
Estimated G Matrix
Effect Row Col1
Intercept 1 2.0263
Estimated G Correlation
Matrix
Effect Row Col1
Intercept 1 1.0000
Covariance Parameter Estimates
Cov Standard
Parm Subject Estimate Error
UN(1,1) subject 2.0263 0.3902
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 110
Solutions for Fixed Effects
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -1.1929 0.3149 558 -3.79 0.0002
time 2 -1.0484 0.3087 558 -3.40 0.0007
time 3 -1.3451 0.3221 558 -4.18 <.0001
time 4 -1.9670 0.3611 558 -5.45 <.0001
time*treat 1 1 0.4529 0.4181 558 1.08 0.2792
time*treat 1 2 0 . . . .
time*treat 2 1 0.5768 0.4101 558 1.41 0.1601
time*treat 2 2 0 . . . .
time*treat 3 1 0.5498 0.4245 558 1.30 0.1958
time*treat 3 2 0 . . . .
time*treat 4 1 0.4371 0.4709 558 0.93 0.3536
time*treat 4 2 0 . . . .
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 558 18.12 <.0001
time*treat 4 558 0.83 0.5039
CC - mixed - PQL 20:20 Monday, May 16, 2005 218
The GLIMMIX Procedure
Model Information
Data Set M.ARMDCC
Response Variable bindif
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By subject
Estimation Technique Residual PL
Degrees of Freedom Method Containment
Class Level Information
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 188 2 4 6 7 8 9 12 13 14 15 16 17 18 19 20 22 23
24 25 26 27 29 33 34 35 36 39 40 42 43 44 45
46 49 51 52 53 54 55 57 58 59 60 61 62 63 64
65 66 67 68 69 70 71 72 74 75 76 77 78 79 80
81 82 83 84 85 86 87 88 89 92 93 94 95 96 99
102 103 104 105 106 107 108 109 110 111 112
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 111
113 115 116 117 118 119 120 121 123 124 125
126 127 128 129 130 132 134 135 137 138 139
140 141 142 143 145 146 149 151 152 153 154
155 156 157 158 159 160 161 162 164 165 166
168 169 170 171 172 173 175 176 178 179 180
181 182 183 184 185 187 188 190 192 193 194
195 199 202 203 205 206 208 209 210 211 212
214 215 217 218 220 221 222 223 224 225 226
227 228 229 232 233 234 235 236 237 238 239
240
Number of Observations Read 752
Number of Observations Used 752
Response Profile
Ordered Total
Value bindif Frequency
1 0 218
2 1 534
The GLIMMIX procedure is modeling the probability that bindif=’0’.
The GLIMMIX Procedure
Dimensions
G-side Cov. Parameters 1
Columns in X 12
Columns in Z per Subject 1
Subjects (Blocks in V) 188
Max Obs per Subject 4
Optimization Information
Optimization Technique Newton-Raphson
Parameters in Optimization 1
Lower Boundaries 1
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
Iteration History
Objective Max
Iteration Restarts Subiterations Function Change Gradient
0 0 4 3373.5642704 0.32012192 4.854E-8
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 112
1 0 3 3451.2809298 0.10686186 4.923E-7
2 0 3 3479.5329722 0.03013256 2.85E-11
3 0 2 3486.3804256 0.00698688 8.052E-8
4 0 2 3487.882408 0.00151187 1.79E-10
5 0 1 3488.2026488 0.00032112 2.989E-6
6 0 1 3488.2704392 0.00006806 1.342E-7
7 0 1 3488.284796 0.00001439 6.003E-9
8 0 1 3488.2878318 0.00000304 2.68E-10
9 0 1 3488.2884735 0.00000064 1.21E-11
10 0 0 3488.2886091 0.00000000 3.619E-6
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Res Log Pseudo-Likelihood 3488.29
Generalized Chi-Square 497.38
Gener. Chi-Square / DF 0.67
CC - mixed - PQL
The GLIMMIX Procedure
Estimated G Matrix
Effect Row Col1
Intercept 1 2.0263
Estimated G Correlation
Matrix
Effect Row Col1
Intercept 1 1.0000
Covariance Parameter Estimates
Cov Standard
Parm Subject Estimate Error
UN(1,1) subject 2.0263 0.3902
Solutions for Fixed Effects
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -1.1929 0.3149 558 -3.79 0.0002
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 113
time 2 -1.0484 0.3087 558 -3.40 0.0007
time 3 -1.3451 0.3221 558 -4.18 <.0001
time 4 -1.9670 0.3611 558 -5.45 <.0001
time*treat 1 1 0.4529 0.4181 558 1.08 0.2792
time*treat 1 2 0 . . . .
time*treat 2 1 0.5768 0.4101 558 1.41 0.1601
time*treat 2 2 0 . . . .
time*treat 3 1 0.5498 0.4245 558 1.30 0.1958
time*treat 3 2 0 . . . .
time*treat 4 1 0.4371 0.4709 558 0.93 0.3536
time*treat 4 2 0 . . . .
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 558 18.12 <.0001
time*treat 4 558 0.83 0.5039
LOCF - mixed - PQL
The GLIMMIX Procedure
Model Information
Data Set M.ARMDLOCF
Response Variable LOCF
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By subject
Estimation Technique Residual PL
Degrees of Freedom Method Containment
Class Level Information
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 234 1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19
20 22 23 24 25 26 27 29 30 31 32 33 34 35 36
37 38 39 40 41 42 43 44 45 46 47 49 50 51 52
53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
68 69 70 71 72 73 74 75 76 77 78 79 80 81 82
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
98 99 100 101 102 103 104 105 106 107 108 109
110 111 112 113 114 115 116 117 118 119 120
121 122 123 124 125 126 127 128 129 130 131
132 133 134 135 136 137 138 139 140 141 142
143 145 146 147 148 149 150 151 152 153 154
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 114
155 156 157 158 159 160 161 162 163 164 165
166 167 168 169 170 171 172 173 174 175 176
177 178 179 180 181 182 183 184 185 186 187
188 190 191 192 193 194 195 196 197 198 199
200 201 202 203 204 205 206 207 208 209 210
211 212 213 214 215 216 217 218 219 220 221
222 223 224 225 226 227 228 229 230 231 232
233 234 235 236 237 238 239 240
Number of Observations Read 960
Number of Observations Used 933
Response Profile
Ordered Total
Value LOCF Frequency
1 0 273
The GLIMMIX procedure is modeling the probability that LOCF=’0’.
LOCF - mixed - PQL
The GLIMMIX Procedure
Response Profile
Ordered Total
Value LOCF Frequency
2 1 660
The GLIMMIX procedure is modeling the probability that LOCF=’0’.
Dimensions
G-side Cov. Parameters 1
Columns in X 12
Columns in Z per Subject 1
Subjects (Blocks in V) 234
Max Obs per Subject 4
Optimization Information
Optimization Technique Newton-Raphson
Parameters in Optimization 1
Lower Boundaries 1
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 115
Iteration History
Objective Max
Iteration Restarts Subiterations Function Change Gradient
0 0 4 4189.2824592 0.31278061 7.91E-8
1 0 3 4298.5207801 0.11492834 1.32E-6
2 0 3 4339.6266764 0.03393012 1.11E-10
3 0 2 4350.2238767 0.00824645 2.055E-7
4 0 2 4352.654268 0.00185764 5.37E-10
5 0 1 4353.1927427 0.00040953 5.923E-6
6 0 1 4353.3109852 0.00009006 2.863E-7
7 0 1 4353.3369649 0.00001975 1.377E-8
8 0 1 4353.3426617 0.00000433 6.62E-10
9 0 1 4353.3439104 0.00000095 3.17E-11
10 0 0 4353.3441841 0.00000000 6.482E-6
Convergence criterion (PCONV=1.11022E-8) satisfied.
LOCF - mixed - PQL
The GLIMMIX Procedure
Fit Statistics
-2 Res Log Pseudo-Likelihood 4353.34
Generalized Chi-Square 588.50
Gener. Chi-Square / DF 0.64
Estimated G Matrix
Effect Row Col1
Intercept 1 2.3422
Estimated G Correlation
Matrix
Effect Row Col1
Intercept 1 1.0000
Covariance Parameter Estimates
Cov Standard
Parm Subject Estimate Error
UN(1,1) subject 2.3422 0.3877
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 116
Solutions for Fixed Effects
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -1.0529 0.2773 693 -3.80 0.0002
time 2 -1.1803 0.2800 693 -4.22 <.0001
time 3 -1.2961 0.2843 693 -4.56 <.0001
time 4 -1.8856 0.3122 693 -6.04 <.0001
time*treat 1 1 0.2370 0.3855 693 0.61 0.5389
time*treat 1 2 0 . . . .
time*treat 2 1 0.6788 0.3825 693 1.77 0.0764
time*treat 2 2 0 . . . .
time*treat 3 1 0.5026 0.3893 693 1.29 0.1971
time*treat 3 2 0 . . . .
time*treat 4 1 0.3874 0.4240 693 0.91 0.3612
time*treat 4 2 0 . . . .
LOCF - mixed - PQL
The GLIMMIX Procedure
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 693 20.29 <.0001
time*treat 4 693 0.98 0.4167
as is - mixed - PQL
The GLIMMIX Procedure
Model Information
Data Set M.ARMDWGEE
Response Variable bindif
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By subject
Estimation Technique Residual PL
Degrees of Freedom Method Containment
Class Level Information
Class Levels Values
time 4 1 2 3 4
treat 2 1 2
subject 234 1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 117
20 22 23 24 25 26 27 29 30 31 32 33 34 35 36
37 38 39 40 41 42 43 44 45 46 47 49 50 51 52
53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
68 69 70 71 72 73 74 75 76 77 78 79 80 81 82
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
98 99 100 101 102 103 104 105 106 107 108 109
110 111 112 113 114 115 116 117 118 119 120
121 122 123 124 125 126 127 128 129 130 131
132 133 134 135 136 137 138 139 140 141 142
143 145 146 147 148 149 150 151 152 153 154
155 156 157 158 159 160 161 162 163 164 165
166 167 168 169 170 171 172 173 174 175 176
177 178 179 180 181 182 183 184 185 186 187
188 190 191 192 193 194 195 196 197 198 199
200 201 202 203 204 205 206 207 208 209 210
211 212 213 214 215 216 217 218 219 220 221
222 223 224 225 226 227 228 229 230 231 232
233 234 235 236 237 238 239 240
Number of Observations Read 960
Number of Observations Used 867
Response Profile
Ordered Total
Value bindif Frequency
1 0 252
The GLIMMIX procedure is modeling the probability that bindif=’0’.
as is - mixed - PQL
The GLIMMIX Procedure
Response Profile
Ordered Total
Value bindif Frequency
2 1 615
The GLIMMIX procedure is modeling the probability that bindif=’0’.
Dimensions
G-side Cov. Parameters 1
Columns in X 12
Columns in Z per Subject 1
Subjects (Blocks in V) 234
Max Obs per Subject 4
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 118
Optimization Information
Optimization Technique Newton-Raphson
Parameters in Optimization 1
Lower Boundaries 1
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
Iteration History
Objective Max
Iteration Restarts Subiterations Function Change Gradient
0 0 4 3883.4998582 0.31708535 3.285E-8
1 0 3 3967.3330478 0.10156883 3.249E-7
2 0 3 3997.4203228 0.02877119 1.9E-11
3 0 2 4004.7088334 0.00677621 7.8E-8
4 0 2 4006.3408848 0.00150218 1.91E-10
5 0 1 4006.698031 0.00032765 3.624E-6
6 0 1 4006.7756985 0.00007134 1.718E-7
7 0 1 4006.7925978 0.00001550 8.11E-9
8 0 1 4006.7962695 0.00000337 3.83E-10
9 0 1 4006.797067 0.00000073 1.8E-11
10 0 0 4006.7972402 0.00000000 5.08E-6
Convergence criterion (PCONV=1.11022E-8) satisfied.
as is - mixed - PQL
The GLIMMIX Procedure
Fit Statistics
-2 Res Log Pseudo-Likelihood 4006.80
Generalized Chi-Square 575.46
Gener. Chi-Square / DF 0.67
Estimated G Matrix
Effect Row Col1
Intercept 1 1.9455
Estimated G Correlation
Matrix
Effect Row Col1
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 119
Intercept 1 1.0000
Covariance Parameter Estimates
Cov Standard
Parm Subject Estimate Error
UN(1,1) subject 1.9455 0.3488
Solutions for Fixed Effects
Standard
Effect time treat Estimate Error DF t Value Pr > |t|
time 1 -1.0028 0.2626 627 -3.82 0.0001
time 2 -1.1886 0.2752 627 -4.32 <.0001
time 3 -1.2573 0.2881 627 -4.36 <.0001
time 4 -2.0235 0.3511 627 -5.76 <.0001
time*treat 1 1 0.2168 0.3666 627 0.59 0.5543
time*treat 1 2 0 . . . .
time*treat 2 1 0.7142 0.3716 627 1.92 0.0551
time*treat 2 2 0 . . . .
time*treat 3 1 0.4932 0.3880 627 1.27 0.2042
time*treat 3 2 0 . . . .
time*treat 4 1 0.4578 0.4592 627 1.00 0.3192
time*treat 4 2 0 . . . .
as is - mixed - PQL
The GLIMMIX Procedure
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
time 4 627 21.02 <.0001
time*treat 4 627 1.15 0.3312
CC - mixed - numerical integration
The NLMIXED Procedure
Specifications
Data Set WORK.HELP
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Newton-Raphson
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 120
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 752
Observations Not Used 0
Total Observations 752
Subjects 188
Max Obs Per Subject 4
Parameters 9
Quadrature Points 20
Parameters
beta11 beta12 beta13 beta14 beta21 beta22 beta23 beta24 tau
1 1 1 1 1 1 1 1 1
Parameters
NegLogLike
436.884377
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 22 394.450701 42.43368 26.03214 -77.1839
2 33 385.186335 9.264366 6.747321 -15.7106
3 44 383.970148 1.216187 1.18193 -2.17069
4 55 383.91831 0.051839 0.060632 -0.10021
5 66 383.918161 0.000148 0.000184 -0.0003
6 77 383.918161 1.398E-9 1.456E-9 -2.8E-9
CC - mixed - numerical integration
The NLMIXED Procedure
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 767.8
AIC (smaller is better) 785.8
AICC (smaller is better) 786.1
BIC (smaller is better) 815.0
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 121
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta11 1.7261 0.4203 187 4.11 <.0001 0.05 0.8970 2.5553 -163E-13
beta12 1.5335 0.4118 187 3.72 0.0003 0.05 0.7212 2.3458 -747E-13
beta13 1.9277 0.4302 187 4.48 <.0001 0.05 1.0790 2.7765 1.53E-11
beta14 2.7405 0.4811 187 5.70 <.0001 0.05 1.7914 3.6896 1.58E-10
beta21 -0.6386 0.5399 187 -1.18 0.2384 0.05 -1.7037 0.4265 1.08E-10
beta22 -0.8086 0.5327 187 -1.52 0.1308 0.05 -1.8596 0.2424 7.43E-11
beta23 -0.7659 0.5467 187 -1.40 0.1629 0.05 -1.8444 0.3126 1.15E-10
beta24 -0.6039 0.5940 187 -1.02 0.3106 0.05 -1.7757 0.5679 1.75E-10
tau 2.1909 0.2670 187 8.21 <.0001 0.05 1.6642 2.7176 -1.46E-9
Additional Estimates
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
tau^2 4.8001 1.1698 187 4.10 <.0001 0.05 2.4923 7.1078
LOCF - mixed - numerical integration
The NLMIXED Procedure
Specifications
Data Set WORK.HELP
Dependent Variable LOCF
Distribution for Dependent Variable Binary
Random Effects b
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Newton-Raphson
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 933
Observations Not Used 27
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 9
Quadrature Points 20
Parameters
beta11 beta12 beta13 beta14 beta21 beta22 beta23 beta24 tau
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 122
1 1 1 1 1 1 1 1 1
Parameters
NegLogLike
534.360977
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 22 478.6083 55.75268 28.85649 -94.3375
2 33 467.330215 11.27808 8.671126 -18.6908
3 44 465.387462 1.942753 1.760915 -3.41454
4 55 465.274339 0.113123 0.124086 -0.2161
5 66 465.27373 0.000609 0.000733 -0.00121
6 77 465.27373 2.115E-8 2.469E-8 -4.23E-8
LOCF - mixed - numerical integration
The NLMIXED Procedure
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 930.5
AIC (smaller is better) 948.5
AICC (smaller is better) 948.7
BIC (smaller is better) 979.6
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta11 1.6327 0.3879 233 4.21 <.0001 0.05 0.8684 2.3969 5.82E-10
beta12 1.8036 0.3923 233 4.60 <.0001 0.05 1.0307 2.5766 3.9E-10
beta13 1.9626 0.3989 233 4.92 <.0001 0.05 1.1768 2.7485 1.117E-9
beta14 2.7632 0.4390 233 6.29 <.0001 0.05 1.8983 3.6280 2.909E-9
beta21 -0.3787 0.5180 233 -0.73 0.4654 0.05 -1.3993 0.6418 2.318E-9
beta22 -0.9835 0.5170 233 -1.90 0.0584 0.05 -2.0022 0.03517 1.895E-9
beta23 -0.7363 0.5226 233 -1.41 0.1602 0.05 -1.7659 0.2934 2.351E-9
beta24 -0.5723 0.5582 233 -1.03 0.3063 0.05 -1.6721 0.5275 3.018E-9
tau 2.4660 0.2680 233 9.20 <.0001 0.05 1.9380 2.9940 -2.47E-8
Additional Estimates
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 123
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
tau^2 6.0812 1.3217 233 4.60 <.0001 0.05 3.4771 8.6853
as is - mixed - numerical integration
The NLMIXED Procedure
Specifications
Data Set WORK.HELP
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Newton-Raphson
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 867
Observations Not Used 93
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 9
Quadrature Points 20
Parameters
beta11 beta12 beta13 beta14 beta21 beta22 beta23 beta24 tau
1 1 1 1 1 1 1 1 1
Parameters
NegLogLike
505.797259
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 22 457.311287 48.48597 27.93691 -87.3977
2 33 447.342964 9.968323 7.182104 -16.9176
3 44 446.067867 1.275097 1.217035 -2.28425
4 55 446.017704 0.050164 0.057482 -0.09723
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 124
5 66 446.017583 0.000121 0.000147 -0.00024
6 77 446.017583 8.06E-10 7.5E-10 -1.61E-9
as is - mixed - numerical integration
The NLMIXED Procedure
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 892.0
AIC (smaller is better) 910.0
AICC (smaller is better) 910.2
BIC (smaller is better) 941.1
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta11 1.4987 0.3584 233 4.18 <.0001 0.05 0.7926 2.2048 -268E-13
beta12 1.7347 0.3726 233 4.66 <.0001 0.05 1.0006 2.4689 -208E-13
beta13 1.8292 0.3877 233 4.72 <.0001 0.05 1.0654 2.5930 6.91E-12
beta14 2.8463 0.4661 233 6.11 <.0001 0.05 1.9280 3.7647 9.48E-11
beta21 -0.3366 0.4806 233 -0.70 0.4844 0.05 -1.2834 0.6103 7.4E-11
beta22 -0.9954 0.4878 233 -2.04 0.0424 0.05 -1.9564 -0.03438 5.81E-11
beta23 -0.6944 0.5036 233 -1.38 0.1693 0.05 -1.6867 0.2979 7.09E-11
beta24 -0.6385 0.5779 233 -1.10 0.2704 0.05 -1.7770 0.5000 9.63E-11
tau 2.1979 0.2514 233 8.74 <.0001 0.05 1.7026 2.6933 -75E-11
Additional Estimates
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
tau^2 4.8308 1.1052 233 4.37 <.0001 0.05 2.6533 7.0083
3. Multiple imputation.
GEE after multiple imputation
Imputation Number=1
The GENMOD Procedure
Model Information
Data Set M.ARMD13C
Distribution Binomial
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 125
Link Function Logit
Dependent Variable bindif
Number of Observations Read 960
Number of Observations Used 956
Number of Events 271
Number of Trials 956
Missing Values 4
Class Level Information
Class Levels Values
time 4 1 2 3 4
subject 240 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71
72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87
...
Response Profile
Ordered Total
Value bindif Frequency
1 0 271
2 1 685
PROC GENMOD is modeling the probability that bindif=’0’. One way to change this to model the
probability that bindif=’1’ is to specify the DESCENDING option in the PROC statement.
Parameter Information
Parameter Effect
Prm1 Intercept
Prm2 time1
Prm3 time2
Prm4 time3
Prm5 time4
Prm6 trttime1
Prm7 trttime2
Prm8 trttime3
Prm9 trttime4
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 126
Deviance 948 1115.3857 1.1766
Scaled Deviance 948 1115.3857 1.1766
Pearson Chi-Square 948 956.0000 1.0084
Scaled Pearson X2 948 956.0000 1.0084
Log Likelihood -557.6928
Algorithm converged.
Estimated Covariance Matrix
Prm2 Prm3 Prm4 Prm5 Prm6 Prm7 Prm8 Prm9
Prm2 0.03968 0 0 0 -0.03968 0 0 0
Prm3 0 0.04349 0 0 0 -0.04349 0 0
Prm4 0 0 0.04444 0 0 0 -0.04444 0
Prm5 0 0 0 0.06000 0 0 0 -0.06000
Prm6 -0.03968 0 0 0 0.07689 0 0 0
Prm7 0 -0.04349 0 0 0 0.07866 0 0
Prm8 0 0 -0.04444 0 0 0 0.08166 0
Prm9 0 0 0 -0.06000 0 0 0 0.11064
Analysis Of Initial Parameter Estimates
Standard Wald 95% Confidence Chi-
Parameter DF Estimate Error Limits Square Pr > ChiSq
Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
time1 1 -0.8473 0.1992 -1.2377 -0.4569 18.09 <.0001
time2 1 -1.0546 0.2086 -1.4634 -0.6459 25.57 <.0001
time3 1 -1.0986 0.2108 -1.5118 -0.6854 27.16 <.0001
time4 1 -1.6094 0.2449 -2.0895 -1.1293 43.17 <.0001
trttime1 1 0.2042 0.2773 -0.3393 0.7477 0.54 0.4616
Analysis Of Initial Parameter Estimates
Standard Wald 95% Confidence Chi-
Parameter DF Estimate Error Limits Square Pr > ChiSq
trttime2 1 0.6281 0.2805 0.0784 1.1778 5.02 0.0251
trttime3 1 0.4555 0.2858 -0.1046 1.0155 2.54 0.1109
trttime4 1 0.2850 0.3326 -0.3669 0.9369 0.73 0.3915
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
Lagrange Multiplier Statistics
Parameter Chi-Square Pr > ChiSq
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 127
Intercept . .
GEE Model Information
Correlation Structure Exchangeable
Within-Subject Effect time (4 levels)
Subject Effect subject (240 levels)
Number of Clusters 240
Clusters With Missing Values 1
Correlation Matrix Dimension 4
Maximum Cluster Size 4
Minimum Cluster Size 0
Algorithm converged.
Exchangeable Working
Correlation
Correlation 0.3902665372
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.0000 0.0000 0.0000 0.0000 . .
time1 -0.8473 0.1992 -1.2377 -0.4569 -4.25 <.0001
time2 -1.0546 0.2086 -1.4634 -0.6459 -5.06 <.0001
time3 -1.0986 0.2108 -1.5118 -0.6854 -5.21 <.0001
time4 -1.6094 0.2449 -2.0895 -1.1293 -6.57 <.0001
trttime1 0.2042 0.2773 -0.3393 0.7477 0.74 0.4616
trttime2 0.6281 0.2805 0.0784 1.1778 2.24 0.0251
trttime3 0.4555 0.2858 -0.1046 1.0155 1.59 0.1109
trttime4 0.2850 0.3326 -0.3669 0.9369 0.86 0.3915
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.0000 0.0000 0.0000 0.0000 . .
time1 -0.8473 0.1992 -1.2377 -0.4569 -4.25 <.0001
time2 -1.0546 0.2086 -1.4634 -0.6459 -5.06 <.0001
time3 -1.0986 0.2108 -1.5118 -0.6854 -5.21 <.0001
time4 -1.6094 0.2449 -2.0895 -1.1293 -6.57 <.0001
trttime1 0.2042 0.2773 -0.3393 0.7477 0.74 0.4616
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 128
trttime2 0.6281 0.2805 0.0784 1.1778 2.24 0.0251
trttime3 0.4555 0.2858 -0.1046 1.0155 1.59 0.1109
trttime4 0.2850 0.3326 -0.3669 0.9369 0.86 0.3915
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
GEE after multiple imputation
Lower Upper Prob
Obs _Imputation_ Parameter DF Estimate StdErr WaldCL WaldCL ChiSq ChiSq
1 1 Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
2 1 time1 1 -0.8473 0.1992 -1.2377 -0.4569 18.09 <.0001
3 1 time2 1 -1.0546 0.2086 -1.4634 -0.6459 25.57 <.0001
4 1 time3 1 -1.0986 0.2108 -1.5118 -0.6854 27.16 <.0001
5 1 time4 1 -1.6094 0.2449 -2.0895 -1.1293 43.17 <.0001
6 1 trttime1 1 0.2042 0.2773 -0.3393 0.7477 0.54 0.4616
7 1 trttime2 1 0.6281 0.2805 0.0784 1.1778 5.02 0.0251
8 1 trttime3 1 0.4555 0.2858 -0.1046 1.0155 2.54 0.1109
9 1 trttime4 1 0.2850 0.3326 -0.3669 0.9369 0.73 0.3915
10 1 Scale 0 1.0000 0.0000 1.0000 1.0000 _ _
11 2 Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
12 2 time1 1 -0.8079 0.1977 -1.1954 -0.4205 16.70 <.0001
13 2 time2 1 -1.0546 0.2086 -1.4634 -0.6459 25.57 <.0001
14 2 time3 1 -1.0986 0.2108 -1.5118 -0.6854 27.16 <.0001
15 2 time4 1 -1.6707 0.2501 -2.1608 -1.1806 44.64 <.0001
16 2 trttime1 1 0.1648 0.2762 -0.3766 0.7061 0.36 0.5508
17 2 trttime2 1 0.6632 0.2800 0.1143 1.2120 5.61 0.0179
18 2 trttime3 1 0.4555 0.2858 -0.1046 1.0155 2.54 0.1109
19 2 trttime4 1 0.3463 0.3364 -0.3131 1.0056 1.06 0.3033
20 2 Scale 0 1.0000 0.0000 1.0000 1.0000 _ _
21 3 Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
22 3 time1 1 -0.8079 0.1977 -1.1954 -0.4205 16.70 <.0001
23 3 time2 1 -1.0116 0.2064 -1.4162 -0.6070 24.01 <.0001
24 3 time3 1 -0.9694 0.2044 -1.3701 -0.5687 22.48 <.0001
25 3 time4 1 -1.6707 0.2501 -2.1608 -1.1806 44.64 <.0001
26 3 trttime1 1 0.1274 0.2770 -0.4156 0.6703 0.21 0.6457
27 3 trttime2 1 0.5851 0.2789 0.0385 1.1317 4.40 0.0359
28 3 trttime3 1 0.3263 0.2811 -0.2247 0.8772 1.35 0.2457
29 3 trttime4 1 0.4447 0.3323 -0.2066 1.0961 1.79 0.1808
30 3 Scale 0 1.0000 0.0000 1.0000 1.0000 _ _
31 4 Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
32 4 time1 1 -0.8873 0.2008 -1.2809 -0.4937 19.52 <.0001
33 4 time2 1 -1.0546 0.2086 -1.4634 -0.6459 25.57 <.0001
34 4 time3 1 -1.0546 0.2086 -1.4634 -0.6459 25.57 <.0001
35 4 time4 1 -1.5506 0.2402 -2.0215 -1.0797 41.66 <.0001
36 4 trttime1 1 0.2442 0.2785 -0.3016 0.7900 0.77 0.3806
37 4 trttime2 1 0.6281 0.2805 0.0784 1.1778 5.02 0.0251
38 4 trttime3 1 0.4115 0.2841 -0.1453 0.9683 2.10 0.1475
39 4 trttime4 1 0.3246 0.3250 -0.3124 0.9616 1.00 0.3179
40 4 Scale 0 1.0000 0.0000 1.0000 1.0000 _ _
41 5 Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
42 5 time1 1 -0.8473 0.1992 -1.2377 -0.4569 18.09 <.0001
43 5 time2 1 -0.9694 0.2044 -1.3701 -0.5687 22.48 <.0001
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 129
44 5 time3 1 -1.0986 0.2108 -1.5118 -0.6854 27.16 <.0001
45 5 time4 1 -1.4392 0.2319 -1.8938 -0.9847 38.51 <.0001
46 5 trttime1 1 0.2412 0.2765 -0.3009 0.7832 0.76 0.3832
47 5 trttime2 1 0.5779 0.2770 0.0351 1.1208 4.35 0.0369
48 5 trttime3 1 0.4555 0.2858 -0.1046 1.0155 2.54 0.1109
49 5 trttime4 1 0.2133 0.3189 -0.4118 0.8383 0.45 0.5036
50 5 Scale 0 1.0000 0.0000 1.0000 1.0000 _ _
51 6 Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
52 6 time1 1 -0.8473 0.1992 -1.2377 -0.4569 18.09 <.0001
53 6 time2 1 -1.0116 0.2064 -1.4162 -0.6070 24.01 <.0001
54 6 time3 1 -1.0116 0.2064 -1.4162 -0.6070 24.01 <.0001
55 6 time4 1 -1.8718 0.2685 -2.3981 -1.3455 48.58 <.0001
56 6 trttime1 1 0.2412 0.2765 -0.3009 0.7832 0.76 0.3832
57 6 trttime2 1 0.5851 0.2789 0.0385 1.1317 4.40 0.0359
58 6 trttime3 1 0.3685 0.2825 -0.1853 0.9222 1.70 0.1922
59 6 trttime4 1 0.6459 0.3464 -0.0332 1.3249 3.48 0.0623
60 6 Scale 0 1.0000 0.0000 1.0000 1.0000 _ _
61 7 Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
62 7 time1 1 -0.8079 0.1977 -1.1954 -0.4205 16.70 <.0001
63 7 time2 1 -0.9280 0.2026 -1.3250 -0.5309 20.98 <.0001
64 7 time3 1 -1.0546 0.2086 -1.4634 -0.6459 25.57 <.0001
65 7 time4 1 -1.6094 0.2449 -2.0895 -1.1293 43.17 <.0001
66 7 trttime1 1 0.1648 0.2762 -0.3766 0.7061 0.36 0.5508
67 7 trttime2 1 0.5015 0.2761 -0.0396 1.0425 3.30 0.0693
68 7 trttime3 1 0.3741 0.2849 -0.1843 0.9324 1.72 0.1891
69 7 trttime4 1 0.3835 0.3285 -0.2603 1.0273 1.36 0.2430
70 7 Scale 0 1.0000 0.0000 1.0000 1.0000 _ _
71 8 Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
72 8 time1 1 -0.8473 0.1992 -1.2377 -0.4569 18.09 <.0001
73 8 time2 1 -1.1436 0.2132 -1.5615 -0.7256 28.76 <.0001
74 8 time3 1 -1.2368 0.2186 -1.6652 -0.8083 32.01 <.0001
75 8 time4 1 -1.5506 0.2402 -2.0215 -1.0797 41.66 <.0001
76 8 trttime1 1 0.2412 0.2765 -0.3009 0.7832 0.76 0.3832
77 8 trttime2 1 0.7170 0.2840 0.1605 1.2736 6.38 0.0116
78 8 trttime3 1 0.5936 0.2915 0.0222 1.1651 4.15 0.0417
79 8 trttime4 1 0.3719 0.3231 -0.2614 1.0053 1.32 0.2497
80 8 Scale 0 1.0000 0.0000 1.0000 1.0000 _ _
81 9 Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
82 9 time1 1 -0.8873 0.2008 -1.2809 -0.4937 19.52 <.0001
83 9 time2 1 -1.0116 0.2064 -1.4162 -0.6070 24.01 <.0001
84 9 time3 1 -0.9280 0.2026 -1.3250 -0.5309 20.98 <.0001
85 9 time4 1 -1.4939 0.2359 -1.9563 -1.0315 40.10 <.0001
86 9 trttime1 1 0.2812 0.2777 -0.2632 0.8255 1.02 0.3114
87 9 trttime2 1 0.5851 0.2789 0.0385 1.1317 4.40 0.0359
88 9 trttime3 1 0.2849 0.2797 -0.2634 0.8331 1.04 0.3085
89 9 trttime4 1 0.2194 0.3238 -0.4153 0.8541 0.46 0.4981
90 9 Scale 0 1.0000 0.0000 1.0000 1.0000 _ _
91 10 Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
92 10 time1 1 -0.8473 0.1992 -1.2377 -0.4569 18.09 <.0001
93 10 time2 1 -0.9694 0.2044 -1.3701 -0.5687 22.48 <.0001
94 10 time3 1 -1.1436 0.2132 -1.5615 -0.7256 28.76 <.0001
95 10 time4 1 -1.6094 0.2449 -2.0895 -1.1293 43.17 <.0001
96 10 trttime1 1 0.2042 0.2773 -0.3393 0.7477 0.54 0.4616
97 10 trttime2 1 0.5779 0.2770 0.0351 1.1208 4.35 0.0369
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 130
98 10 trttime3 1 0.5740 0.2862 0.0132 1.1349 4.02 0.0449
99 10 trttime4 1 0.4308 0.3267 -0.2094 1.0710 1.74 0.1872
100 10 Scale 0 1.0000 0.0000 1.0000 1.0000 _ _
_
I
m
p
u
t R
a o
t w
i N P P P P P P P P
O o a r r r r r r r r
b n m m m m m m m m m
s _ e 2 3 4 5 6 7 8 9
1 1 Prm2 0.0396825 0 0 0 -0.039683 0 0 0
2 1 Prm3 0 0.043494 0 0 0 -0.043494 0 0
3 1 Prm4 0 0 0.0444444 0 0 0 -0.044444 0
4 1 Prm5 0 0 0 0.06 0 0 0 -0.06
5 1 Prm6 -0.039683 0 0 0 0.0768933 0 0 0
6 1 Prm7 0 -0.043494 0 0 0 0.0786595 0 0
7 1 Prm8 0 0 -0.044444 0 0 0 0.0816552 0
8 1 Prm9 0 0 0 -0.06 0 0 0 0.1106383
9 2 Prm2 0.0390752 0 0 0 -0.039075 0 0 0
10 2 Prm3 0 0.043494 0 0 0 -0.043494 0 0
11 2 Prm4 0 0 0.0444444 0 0 0 -0.044444 0
12 2 Prm5 0 0 0 0.0625326 0 0 0 -0.062533
13 2 Prm6 -0.039075 0 0 0 0.076286 0 0 0
14 2 Prm7 0 -0.043494 0 0 0 0.0784119 0 0
15 2 Prm8 0 0 -0.044444 0 0 0 0.0816552 0
16 2 Prm9 0 0 0 -0.062533 0 0 0 0.1131709
...
The MIANALYZE Procedure
Model Information
PARMS Data Set WORK.GMPARMS
PARMINFO Data Set WORK.GMPINFO
COVB Data Set WORK.GMCOVB
Number of Imputations 10
Multiple Imputation Variance Information
-----------------Variance-----------------
Parameter Between Within Total DF
time1 0.000856 0.039631 0.040573 16698
time2 0.003629 0.042843 0.046835 1238.9
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 131
time3 0.007760 0.043903 0.052440 339.63
time4 0.013950 0.060207 0.075551 218.18
trttime1 0.002235 0.076721 0.079179 9337.3
trttime2 0.003376 0.077934 0.081648 4350.7
trttime3 0.009839 0.081079 0.091902 648.95
trttime4 0.015836 0.108550 0.125969 470.66
Multiple Imputation Variance Information
Relative Fraction
Increase Missing Relative
Parameter in Variance Information Efficiency
time1 0.023768 0.023333 0.997672
time2 0.093173 0.086705 0.991404
time3 0.194438 0.167673 0.983509
time4 0.254868 0.210309 0.979402
trttime1 0.032041 0.031254 0.996884
trttime2 0.047649 0.045921 0.995429
trttime3 0.133485 0.120471 0.988096
trttime4 0.160474 0.141922 0.986006
Multiple Imputation Parameter Estimates
Parameter Estimate Std Error 95% Confidence Limits DF
time1 -0.843486 0.201427 -1.23831 -0.44867 16698
time2 -1.020910 0.216413 -1.44549 -0.59633 1238.9
time3 -1.069445 0.228997 -1.51988 -0.61901 339.63
time4 -1.607580 0.274866 -2.14931 -1.06585 218.18
trttime1 0.211407 0.281388 -0.34017 0.76299 9337.3
trttime2 0.604904 0.285740 0.04471 1.16510 4350.7
trttime3 0.429925 0.303153 -0.16535 1.02521 648.95
trttime4 0.366539 0.354921 -0.33089 1.06396 470.66
Multiple Imputation Parameter Estimates
t for H0:
Parameter Minimum Maximum Theta0 Parameter=Theta0 Pr > |t|
time1 -0.887303 -0.807923 0 -4.19 <.0001
time2 -1.143564 -0.927987 0 -4.72 <.0001
time3 -1.236763 -0.927987 0 -4.67 <.0001
time4 -1.871802 -1.439215 0 -5.85 <.0001
trttime1 0.127354 0.281167 0 0.75 0.4525
trttime2 0.501468 0.717045 0 2.12 0.0343
trttime3 0.284850 0.593626 0 1.42 0.1566
trttime4 0.213264 0.645850 0 1.03 0.3023
Within-Imputation Covariance Matrix
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 132
time1 time2 time3 time4
time1 0.0396310626 0.0000000000 0.0000000000 0.0000000000
time2 0.0000000000 0.0428428975 0.0000000000 0.0000000000
time3 0.0000000000 0.0000000000 0.0439033458 0.0000000000
time4 0.0000000000 0.0000000000 0.0000000000 0.0602066141
trttime1 -.0396310626 0.0000000000 0.0000000000 0.0000000000
trttime2 0.0000000000 -.0428428975 0.0000000000 0.0000000000
trttime3 0.0000000000 0.0000000000 -.0439033458 0.0000000000
trttime4 0.0000000000 0.0000000000 0.0000000000 -.0602066141
Within-Imputation Covariance Matrix
trttime1 trttime2 trttime3 trttime4
time1 -.0396310626 0.0000000000 0.0000000000 0.0000000000
time2 0.0000000000 -.0428428975 0.0000000000 0.0000000000
time3 0.0000000000 0.0000000000 -.0439033458 0.0000000000
time4 0.0000000000 0.0000000000 0.0000000000 -.0602066141
trttime1 0.0767208784 0.0000000000 0.0000000000 0.0000000000
trttime2 0.0000000000 0.0779340889 0.0000000000 0.0000000000
trttime3 0.0000000000 0.0000000000 0.0810791448 0.0000000000
trttime4 0.0000000000 0.0000000000 0.0000000000 0.1085496567
Between-Imputation Covariance Matrix
time1 time2 time3 time4
time1 0.0008563099 0.0004082521 -.0003197344 -.0013188041
time2 0.0004082521 0.0036288964 0.0023147112 -.0000340066
time3 -.0003197344 0.0023147112 0.0077604498 -.0019018583
time4 -.0013188041 -.0000340066 -.0019018583 0.0139497428
trttime1 -.0012313718 -.0006629132 -.0000847749 0.0018887228
trttime2 -.0002994706 -.0033591680 -.0028303911 0.0004365905
trttime3 0.0001406515 -.0022799319 -.0084281421 0.0018943906
trttime4 0.0011677226 0.0003481757 0.0005081848 -.0135624411
Between-Imputation Covariance Matrix
trttime1 trttime2 trttime3 trttime4
time1 -.0012313718 -.0002994706 0.0001406515 0.0011677226
time2 -.0006629132 -.0033591680 -.0022799319 0.0003481757
time3 -.0000847749 -.0028303911 -.0084281421 0.0005081848
time4 0.0018887228 0.0004365905 0.0018943906 -.0135624411
trttime1 0.0022347438 0.0005690403 0.0002194178 -.0015574154
trttime2 0.0005690403 0.0033759208 0.0030399236 -.0007737411
trttime3 0.0002194178 0.0030399236 0.0098389196 -.0000532713
trttime4 -.0015574154 -.0007737411 -.0000532713 0.0158357980
Total Covariance Matrix
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 133
time1 time2 time3 time4
time1 0.0429818143 0.0000000000 0.0000000000 0.0000000000
time2 0.0000000000 0.0464652054 0.0000000000 0.0000000000
time3 0.0000000000 0.0000000000 0.0476153131 0.0000000000
time4 0.0000000000 0.0000000000 0.0000000000 0.0652970002
trttime1 -.0429818143 0.0000000000 0.0000000000 0.0000000000
trttime2 0.0000000000 -.0464652054 0.0000000000 0.0000000000
trttime3 0.0000000000 0.0000000000 -.0476153131 0.0000000000
trttime4 0.0000000000 0.0000000000 0.0000000000 -.0652970002
Total Covariance Matrix
trttime1 trttime2 trttime3 trttime4
time1 -.0429818143 0.0000000000 0.0000000000 0.0000000000
time2 0.0000000000 -.0464652054 0.0000000000 0.0000000000
time3 0.0000000000 0.0000000000 -.0476153131 0.0000000000
time4 0.0000000000 0.0000000000 0.0000000000 -.0652970002
trttime1 0.0832075228 0.0000000000 0.0000000000 0.0000000000
trttime2 0.0000000000 0.0845233085 0.0000000000 0.0000000000
trttime3 0.0000000000 0.0000000000 0.0879342745 0.0000000000
trttime4 0.0000000000 0.0000000000 0.0000000000 0.1177273803
NLMIXED after multiple imputation
The NLMIXED Procedure
Specifications
Data Set M.ARMD13C
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Newton-Raphson
Integration Method Adaptive Gaussian
Quadrature
Imputation Number=1
The NLMIXED Procedure
Dimensions
Observations Used 956
Observations Not Used 4
Total Observations 960
Subjects 239
Max Obs Per Subject 4
Parameters 9
Quadrature Points 20
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 134
Parameters
beta11 beta12 beta13 beta14 beta21 beta22 beta23 beta24 tau
1 1 1 1 1 1 1 1 1
Parameters
NegLogLike
545.864244
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 22 493.592025 52.27222 27.84385 -91.265
2 33 483.920182 9.671844 7.473753 -16.282
3 44 482.586491 1.333691 1.280772 -2.38803
4 55 482.533795 0.052696 0.060668 -0.10216
5 66 482.53367 0.000125 0.000154 -0.00025
6 77 482.53367 8.03E-10 7.6E-10 -1.61E-9
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 965.1
AIC (smaller is better) 983.1
AICC (smaller is better) 983.3
BIC (smaller is better) 1014.4
The NLMIXED Procedure
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta11 1.4664 0.3482 238 4.21 <.0001 0.05 0.7804 2.1524 -743E-14
beta12 1.8086 0.3611 238 5.01 <.0001 0.05 1.0972 2.5200 5.63E-12
beta13 1.8803 0.3641 238 5.16 <.0001 0.05 1.1630 2.5977 2.45E-11
beta14 2.6907 0.4060 238 6.63 <.0001 0.05 1.8908 3.4905 9.92E-11
beta21 -0.2967 0.4749 238 -0.62 0.5326 0.05 -1.2322 0.6387 8.4E-11
beta22 -1.0237 0.4799 238 -2.13 0.0339 0.05 -1.9692 -0.07828 7.25E-11
beta23 -0.7107 0.4838 238 -1.47 0.1432 0.05 -1.6637 0.2424 8.52E-11
beta24 -0.3622 0.5276 238 -0.69 0.4931 0.05 -1.4017 0.6772 1.07E-10
tau 2.2181 0.2409 238 9.21 <.0001 0.05 1.7435 2.6927 -76E-11
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 135
Covariance Matrix of Parameter Estimates
Row Parameter beta11 beta12 beta13 beta14 beta21 beta22 beta23 beta24
1 beta11 0.1213 0.05701 0.05737 0.06086 -0.1143 -0.05181 -0.05038 -0.04892
2 beta12 0.05701 0.1304 0.05976 0.06429 -0.04886 -0.1243 -0.05160 -0.05037
3 beta13 0.05737 0.05976 0.1326 0.06498 -0.04898 -0.05351 -0.1242 -0.05066
4 beta14 0.06086 0.06429 0.06498 0.1649 -0.04988 -0.05612 -0.05401 -0.1461
5 beta21 -0.1143 -0.04886 -0.04898 -0.04988 0.2255 0.09419 0.09468 0.09549
6 beta22 -0.05181 -0.1243 -0.05351 -0.05612 0.09419 0.2303 0.09590 0.09567
7 beta23 -0.05038 -0.05160 -0.1242 -0.05401 0.09468 0.09590 0.2340 0.09723
8 beta24 -0.04892 -0.05037 -0.05066 -0.1461 0.09549 0.09567 0.09723 0.2784
9 tau 0.02181 0.02544 0.02618 0.03422 -0.00320 -0.01159 -0.00757 -0.00246
Covariance
Matrix of
Parameter
Estimates
Row tau
1 0.02181
2 0.02544
3 0.02618
4 0.03422
5 -0.00320
6 -0.01159
7 -0.00757
8 -0.00246
9 0.05804
Additional Estimates
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
tau2 4.9200 1.0688 238 4.60 <.0001 0.05 2.8146 7.0255
Covariance Matrix of
Additional Estimates
Row Label Cov1
1 tau2 1.1422
The MIANALYZE Procedure
Model Information
PARMS Data Set WORK.NLPARMS
COVB Data Set WORK.NLCOVB
Number of Imputations 10
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 136
Multiple Imputation Variance Information
-----------------Variance-----------------
Parameter Between Within Total DF
beta11 0.006200 0.120558 0.127378 3139.1
beta12 0.012235 0.128374 0.141832 999.52
beta13 0.014881 0.130702 0.147071 726.52
beta14 0.030602 0.165001 0.198664 313.46
beta21 0.007052 0.223534 0.231291 8002.1
beta22 0.009883 0.227435 0.238307 4324.6
beta23 0.023720 0.231383 0.257475 876.41
beta24 0.040058 0.273874 0.317938 468.56
Multiple Imputation Variance Information
Relative Fraction
Increase Missing Relative
Parameter in Variance Information Efficiency
beta11 0.056574 0.054147 0.994614
beta12 0.104839 0.096697 0.990423
beta13 0.125240 0.113737 0.988754
beta14 0.204013 0.174693 0.982831
beta21 0.034700 0.033778 0.996634
beta22 0.047800 0.046061 0.995415
beta23 0.112764 0.103381 0.989768
beta24 0.160891 0.142246 0.985975
Multiple Imputation Parameter Estimates
Parameter Estimate Std Error 95% Confidence Limits DF
beta11 1.455346 0.356901 0.75556 2.15513 3139.1
Multiple Imputation Parameter Estimates
t for H0:
Parameter Minimum Maximum Theta0 Parameter=Theta0 Pr > |t|
beta11 1.338106 1.582843 0 4.08 <.0001
MIANALYZE for NLMIXED 16:58 Sunday, December 26, 2004 885
The MIANALYZE Procedure
Multiple Imputation Parameter Estimates
Parameter Estimate Std Error 95% Confidence Limits DF
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 137
beta12 1.749244 0.376606 1.01021 2.48827 999.52
beta13 1.826672 0.383498 1.07377 2.57957 726.52
beta14 2.686402 0.445717 1.80943 3.56338 313.46
beta21 -0.315416 0.480927 -1.25816 0.62733 8002.1
beta22 -0.988679 0.488167 -1.94574 -0.03162 4324.6
beta23 -0.673317 0.507420 -1.66922 0.32258 876.41
beta24 -0.515931 0.563860 -1.62394 0.59208 468.56
Multiple Imputation Parameter Estimates
t for H0:
Parameter Minimum Maximum Theta0 Parameter=Theta0 Pr > |t|
beta12 1.529515 1.882212 0 4.64 <.0001
beta13 1.653527 2.028812 0 4.76 <.0001
beta14 2.481554 3.074676 0 6.03 <.0001
beta21 -0.445510 -0.192473 0 -0.66 0.5119
beta22 -1.126595 -0.769312 0 -2.03 0.0429
beta23 -0.907306 -0.449662 0 -1.33 0.1849
beta24 -0.954038 -0.276338 0 -0.91 0.3607
The MIANALYZE Procedure
Model Information
PARMS Data Set WORK.NLPARMS
COVB Data Set WORK.NLCOVB
Number of Imputations 10
Multiple Imputation Variance Information
-----------------Variance-----------------
Parameter Between Within Total DF
beta11 0.006200 0.120558 0.127378 3139.1
beta12 0.012235 0.128374 0.141832 999.52
beta13 0.014881 0.130702 0.147071 726.52
beta14 0.030602 0.165001 0.198664 313.46
beta21 0.007052 0.223534 0.231291 8002.1
beta22 0.009883 0.227435 0.238307 4324.6
beta23 0.023720 0.231383 0.257475 876.41
beta24 0.040058 0.273874 0.317938 468.56
tau 0.008134 0.056946 0.065893 488.15
Multiple Imputation Variance Information
Relative Fraction
Increase Missing Relative
Parameter in Variance Information Efficiency
beta11 0.056574 0.054147 0.994614
beta12 0.104839 0.096697 0.990423
beta13 0.125240 0.113737 0.988754
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 138
beta14 0.204013 0.174693 0.982831
beta21 0.034700 0.033778 0.996634
beta22 0.047800 0.046061 0.995415
beta23 0.112764 0.103381 0.989768
beta24 0.160891 0.142246 0.985975
tau 0.157117 0.139302 0.986261
Multiple Imputation Parameter Estimates
Parameter Estimate Std Error 95% Confidence Limits DF
beta11 1.455346 0.356901 0.75556 2.15513 3139.1
beta12 1.749244 0.376606 1.01021 2.48827 999.52
beta13 1.826672 0.383498 1.07377 2.57957 726.52
beta14 2.686402 0.445717 1.80943 3.56338 313.46
beta21 -0.315416 0.480927 -1.25816 0.62733 8002.1
beta22 -0.988679 0.488167 -1.94574 -0.03162 4324.6
beta23 -0.673317 0.507420 -1.66922 0.32258 876.41
beta24 -0.515931 0.563860 -1.62394 0.59208 468.56
The MIANALYZE Procedure
Multiple Imputation Parameter Estimates
Parameter Estimate Std Error 95% Confidence Limits DF
tau 2.203316 0.256697 1.69895 2.70768 488.15
Multiple Imputation Parameter Estimates
t for H0:
Parameter Minimum Maximum Theta0 Parameter=Theta0 Pr > |t|
beta11 1.338106 1.582843 0 4.08 <.0001
beta12 1.529515 1.882212 0 4.64 <.0001
beta13 1.653527 2.028812 0 4.76 <.0001
beta14 2.481554 3.074676 0 6.03 <.0001
beta21 -0.445510 -0.192473 0 -0.66 0.5119
beta22 -1.126595 -0.769312 0 -2.03 0.0429
beta23 -0.907306 -0.449662 0 -1.33 0.1849
beta24 -0.954038 -0.276338 0 -0.91 0.3607
tau 2.081615 2.332432 0 8.58 <.0001
4. Results of PQL and MQL.
PQL REML
The GLIMMIX Procedure
Model Information
Data Set M.ARMD
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 139
Response Variable bindif
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By subject
Estimation Technique Residual PL
Degrees of Freedom Method Containment
Class Level Information
Class Levels Values
subject 234 1 2 3 4 6 7 8 9 10 11 12 13 14 15 16 17 18 19
20 22 23 24 25 26 27 29 30 31 32 33 34 35 36
37 38 39 40 41 42 43 44 45 46 47 49 50 51 52
53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
68 69 70 71 72 73 74 75 76 77 78 79 80 81 82
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
98 99 100 ...
Number of Observations Read 960
Number of Observations Used 867
Response Profile
Ordered Total
Value bindif Frequency
1 0 252
2 1 615
The GLIMMIX procedure is modeling the probability that bindif=’1’.
Dimensions
G-side Cov. Parameters 1
Columns in X 3
Columns in Z per Subject 1
Subjects (Blocks in V) 234
Max Obs per Subject 4
Optimization Information
Optimization Technique Dual Quasi-Newton
Parameters in Optimization 1
Lower Boundaries 1
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 140
Iteration History
Objective Max
Iteration Restarts Subiterations Function Change Gradient
0 0 4 3893.4790252 0.30055232 0.000151
1 0 3 3972.9263817 0.09539047 0.000236
2 0 3 4000.5480588 0.02662055 0.000017
3 0 2 4007.1652454 0.00622526 0.000016
4 0 3 4008.6430457 0.00137635 4.613E-8
5 0 2 4008.9659864 0.00030013 2.148E-6
6 0 2 4009.0362183 0.00006515 1.012E-7
7 0 1 4009.0514556 0.00002402 0.000321
8 0 1 4009.0570731 0.00000792 0.000106
9 0 1 4009.055221 0.00000261 0.000035
10 0 1 4009.0558317 0.00000086 0.000011
11 0 0 4009.0556303 0.00000000 5.426E-6
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Res Log Pseudo-Likelihood 4009.06
Generalized Chi-Square 578.91
Gener. Chi-Square / DF 0.67
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
Intercept subject 1.9113 0.3432
Solutions for Fixed Effects
Standard
Effect Estimate Error DF t Value Pr > |t|
Intercept 0.6637 0.1593 233 4.17 <.0001
timec 0.01491 0.005979 631 2.49 0.0129
timec*treat 0.01018 0.008135 631 1.25 0.2113
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
timec 1 631 6.22 0.0129
timec*treat 1 631 1.57 0.2113
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 141
PQL ML
The GLIMMIX Procedure
Model Information
Data Set M.ARMD
Response Variable bindif
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By subject
Estimation Technique PL
Degrees of Freedom Method Containment
Number of Observations Read 960
Number of Observations Used 867
Response Profile
Ordered Total
Value bindif Frequency
1 0 252
2 1 615
The GLIMMIX procedure is modeling the probability that bindif=’1’.
Dimensions
G-side Cov. Parameters 1
Columns in X 3
Columns in Z per Subject 1
Subjects (Blocks in V) 234
Max Obs per Subject 4
Optimization Information
Optimization Technique Dual Quasi-Newton
Parameters in Optimization 1
Lower Boundaries 1
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
Convergence criterion (PCONV=1.11022E-8) satisfied.
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 142
Fit Statistics
-2 Log Pseudo-Likelihood 3986.53
Generalized Chi-Square 580.15
Gener. Chi-Square / DF 0.67
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
Intercept subject 1.8813 0.3386
Solutions for Fixed Effects
Standard
Effect Estimate Error DF t Value Pr > |t|
Intercept 0.6625 0.1587 233 4.17 <.0001
timec 0.01484 0.005967 631 2.49 0.0131
timec*treat 0.01021 0.008111 631 1.26 0.2088
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
timec 1 631 6.19 0.0131
timec*treat 1 631 1.58 0.2088
MQL REML
The GLIMMIX Procedure
Model Information
Data Set M.ARMD
Response Variable bindif
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By subject
Estimation Technique Residual MPL
Degrees of Freedom Method Containment
Number of Observations Read 960
Number of Observations Used 867
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 143
Response Profile
Ordered Total
Value bindif Frequency
1 0 252
2 1 615
The GLIMMIX procedure is modeling the probability that bindif=’1’.
Dimensions
G-side Cov. Parameters 1
Columns in X 3
Columns in Z per Subject 1
Subjects (Blocks in V) 234
Max Obs per Subject 4
Optimization Information
Optimization Technique Dual Quasi-Newton
Parameters in Optimization 1
Lower Boundaries 1
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Res Log Pseudo-Likelihood 3794.36
Generalized Chi-Square 618.55
Gener. Chi-Square / DF 0.72
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
Intercept subject 1.4124 0.2545
Solutions for Fixed Effects
Standard
Effect Estimate Error DF t Value Pr > |t|
Intercept 0.5682 0.1404 233 4.05 <.0001
timec 0.01146 0.005373 631 2.13 0.0334
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 144
timec*treat 0.009728 0.007188 631 1.35 0.1764
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
timec 1 631 4.55 0.0334
timec*treat 1 631 1.83 0.1764
MQL ML
The GLIMMIX Procedure
Model Information
Data Set M.ARMD
Response Variable bindif
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By subject
Estimation Technique MPL
Degrees of Freedom Method Containment
Number of Observations Read 960
Number of Observations Used 867
Response Profile
Ordered Total
Value bindif Frequency
1 0 252
2 1 615
The GLIMMIX procedure is modeling the probability that bindif=’1’.
Dimensions
G-side Cov. Parameters 1
Columns in X 3
Columns in Z per Subject 1
Subjects (Blocks in V) 234
Max Obs per Subject 4
Optimization Information
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 145
Optimization Technique Dual Quasi-Newton
Parameters in Optimization 1
Lower Boundaries 1
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Log Pseudo-Likelihood 3774.81
Generalized Chi-Square 619.98
Gener. Chi-Square / DF 0.72
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
Intercept subject 1.3956 0.2523
Solutions for Fixed Effects
Standard
Effect Estimate Error DF t Value Pr > |t|
Intercept 0.5682 0.1401 233 4.06 <.0001
timec 0.01144 0.005370 631 2.13 0.0335
timec*treat 0.009758 0.007179 631 1.36 0.1746
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
timec 1 631 4.54 0.0335
timec*treat 1 631 1.85 0.1746
5. Results of Gaussian Quadrature
Initial Values
The GENMOD Procedure
Model Information
Data Set M.ARMD
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 146
Distribution Binomial
Link Function Logit
Dependent Variable bindif
Number of Observations Read 960
Number of Observations Used 867
Number of Events 615
Number of Trials 867
Missing Values 93
Response Profile
Ordered Total
Value bindif Frequency
1 1 615
2 0 252
PROC GENMOD is modeling the probability that bindif=’1’.
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 864 1028.1346 1.1900
Scaled Deviance 864 1028.1346 1.1900
Pearson Chi-Square 864 867.9430 1.0046
Scaled Pearson X2 864 867.9430 1.0046
Log Likelihood -514.0673
Algorithm converged.
Analysis Of Parameter Estimates
Standard Wald 95% Confidence Chi-
Parameter DF Estimate Error Limits Square Pr > ChiSq
Intercept 1 0.5670 0.1167 0.3383 0.7956 23.62 <.0001
timec 1 0.0098 0.0050 0.0000 0.0196 3.87 0.0492
timec*treat 1 0.0133 0.0060 0.0015 0.0251 4.87 0.0273
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
MML GQ 25
The NLMIXED Procedure
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 147
Specifications
Data Set M.ARMD
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Dual Quasi-Newton
Integration Method Gaussian Quadrature
Dimensions
Observations Used 867
Observations Not Used 93
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 4
Quadrature Points 25
Parameters
beta0 beta1 beta2 sigmab NegLogLike
0.567 0.0098 0.0133 2 456.839932
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 451.981825 4.858107 125.1142 -5664.22
2 7 451.75583 0.225995 148.1353 -34.8464
3 9 450.232672 1.523158 148.7488 -1.52912
4 11 449.371915 0.860757 13.61276 -0.74256
5 13 449.327407 0.044507 13.61007 -0.04633
6 14 449.303743 0.023664 11.90489 -0.02619
7 16 449.292117 0.011626 0.156812 -0.02244
8 18 449.292115 2.304E-6 0.007391 -4.56E-6
9 20 449.292115 6.26E-9 0.000469 -1.15E-8
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 898.6
AIC (smaller is better) 906.6
AICC (smaller is better) 906.6
BIC (smaller is better) 920.4
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 148
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta0 1.0168 0.2271 233 4.48 <.0001 0.05 0.5694 1.4641 2.666E-6
beta1 0.02112 0.007315 233 2.89 0.0042 0.05 0.006712 0.03554 0.000469
beta2 0.01091 0.01019 233 1.07 0.2856 0.05 -0.00917 0.03099 0.000237
sigmab 2.1864 0.2510 233 8.71 <.0001 0.05 1.6918 2.6809 -6.68E-6
Additional Estimates
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
sigmab^2 4.7802 1.0977 233 4.35 <.0001 0.05 2.6175 6.9428
MML GQ 51
The NLMIXED Procedure
Specifications
Data Set M.ARMD
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Dual Quasi-Newton
Integration Method Gaussian Quadrature
Dimensions
Observations Used 867
Observations Not Used 93
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 4
Quadrature Points 51
Parameters
beta0 beta1 beta2 sigmab NegLogLike
0.567 0.0098 0.0133 2 456.839837
Iteration History
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 149
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 451.983217 4.856621 124.87 -5660.5
2 7 451.757185 0.226032 147.9446 -34.8474
3 9 450.235463 1.521722 148.7502 -1.52714
4 11 449.374938 0.860525 13.66278 -0.74259
5 13 449.330649 0.044289 13.67193 -0.04632
6 14 449.307685 0.022965 12.29056 -0.02598
7 16 449.29571 0.011975 0.152137 -0.02313
8 18 449.295708 1.801E-6 0.007551 -3.54E-6
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 898.6
AIC (smaller is better) 906.6
Fit Statistics
AICC (smaller is better) 906.6
BIC (smaller is better) 920.4
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta0 1.0170 0.2273 233 4.47 <.0001 0.05 0.5692 1.4648 0.000547
beta1 0.02113 0.007314 233 2.89 0.0042 0.05 0.006719 0.03554 0.007551
beta2 0.01089 0.01019 233 1.07 0.2865 0.05 -0.00919 0.03097 0.002419
sigmab 2.1850 0.2500 233 8.74 <.0001 0.05 1.6924 2.6776 -0.0003
Additional Estimates
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
sigmab^2 4.7744 1.0927 233 4.37 <.0001 0.05 2.6216 6.9271
MML Laplace
The NLMIXED Procedure
Specifications
Data Set M.ARMD
Dependent Variable bindif
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 150
Distribution for Dependent Variable Binary
Random Effects b
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 867
Observations Not Used 93
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 4
Quadrature Points 1
Parameters
beta0 beta1 beta2 sigmab NegLogLike
0.567 0.0098 0.0133 2 462.458846
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 457.050292 5.408554 136.2014 -6291.71
2 7 456.814449 0.235842 160.1404 -35.5955
3 9 454.972757 1.841692 165.5178 -1.82297
4 11 454.144846 0.827912 18.57783 -0.86111
5 13 454.099807 0.045039 19.46722 -0.04876
6 14 454.061138 0.038669 11.38215 -0.03014
7 16 454.055794 0.005344 0.571366 -0.01023
8 18 454.055783 0.000011 0.004151 -0.00002
9 20 454.055783 1.592E-8 0.000108 -2.97E-8
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 908.1
AIC (smaller is better) 916.1
AICC (smaller is better) 916.2
BIC (smaller is better) 929.9
Parameter Estimates
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 151
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta0 1.0382 0.2264 233 4.59 <.0001 0.05 0.5922 1.4842 -4.39E-6
beta1 0.02041 0.007220 233 2.83 0.0051 0.05 0.006188 0.03464 0.000108
beta2 0.01128 0.009975 233 1.13 0.2593 0.05 -0.00837 0.03093 -0.00005
sigmab 2.0543 0.2380 233 8.63 <.0001 0.05 1.5853 2.5233 1.078E-6
Additional Estimates
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
sigmab^2 4.2202 0.9779 233 4.32 <.0001 0.05 2.2934 6.1469
MML AGQ 5
The NLMIXED Procedure
Specifications
Data Set M.ARMD
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 867
Observations Not Used 93
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 4
Quadrature Points 5
Parameters
beta0 beta1 beta2 sigmab NegLogLike
0.567 0.0098 0.0133 2 457.266838
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 152
1 4 452.37829 4.888548 124.7635 -5686.5
2 7 452.152399 0.225891 147.905 -34.8432
3 9 450.700052 1.452347 143.1303 -1.4782
4 11 449.928621 0.771431 12.92075 -0.69273
5 13 449.898346 0.030275 13.53213 -0.03481
6 14 449.885732 0.012614 15.18799 -0.01832
7 15 449.87628 0.009452 5.89114 -0.02185
8 17 449.874431 0.001849 0.114113 -0.00374
9 19 449.87443 4.934E-7 0.000905 -9.67E-7
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 899.7
AIC (smaller is better) 907.7
AICC (smaller is better) 907.8
BIC (smaller is better) 921.6
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta0 0.9940 0.2210 233 4.50 <.0001 0.05 0.5586 1.4294 0.000057
beta1 0.02090 0.007262 233 2.88 0.0044 0.05 0.006592 0.03521 0.000726
beta2 0.01102 0.01009 233 1.09 0.2758 0.05 -0.00885 0.03089 0.000905
sigmab 2.1232 0.2328 233 9.12 <.0001 0.05 1.6645 2.5819 -0.00019
Additional Estimates
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
sigmab^2 4.5081 0.9887 233 4.56 <.0001 0.05 2.5602 6.4560
MML AGQ 11
The NLMIXED Procedure
Specifications
Data Set M.ARMD
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Dual Quasi-Newton
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 153
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 867
Observations Not Used 93
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 4
Quadrature Points 11
Parameters
beta0 beta1 beta2 sigmab NegLogLike
0.567 0.0098 0.0133 2 456.835902
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 451.979375 4.856526 124.8787 -5660.55
2 7 451.75333 0.226045 147.9511 -34.8481
3 9 450.229448 1.523882 148.9323 -1.52855
4 11 449.366036 0.863412 13.69402 -0.74424
5 13 449.320871 0.045165 13.67323 -0.04692
6 14 449.296972 0.023898 11.8723 -0.02656
7 16 449.285127 0.011845 0.15199 -0.02286
8 18 449.285125 2.285E-6 0.007377 -4.52E-6
9 20 449.285125 6.276E-9 0.000473 -1.15E-8
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 898.6
AIC (smaller is better) 906.6
AICC (smaller is better) 906.6
BIC (smaller is better) 920.4
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta0 1.0181 0.2277 233 4.47 <.0001 0.05 0.5695 1.4666 2.801E-6
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 154
beta1 0.02114 0.007316 233 2.89 0.0042 0.05 0.006722 0.03555 0.000473
beta2 0.01088 0.01020 233 1.07 0.2869 0.05 -0.00920 0.03097 0.000243
sigmab 2.1874 0.2512 233 8.71 <.0001 0.05 1.6925 2.6823 -6.73E-6
Additional Estimates
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
sigmab^2 4.7846 1.0989 233 4.35 <.0001 0.05 2.6195 6.9496
Empirical Bayes Estimates
The UNIVARIATE Procedure
Variable: Estimate (Empirical Bayes Estimate)
Moments
N 240 Sum Weights 240
Mean -0.2015791 Sum Observations -48.378989
Std Deviation 1.46466961 Variance 2.14525706
Skewness -0.5771659 Kurtosis -0.9872685
Uncorrected SS 522.468632 Corrected SS 512.716438
Coeff Variation -726.59787 Std Error Mean 0.09454402
Basic Statistical Measures
Location Variability
Mean -0.20158 Std Deviation 1.46467
Median -0.14263 Variance 2.14526
Mode 1.13816 Range 4.62938
Interquartile Range 2.55898
NOTE: The mode displayed is the smallest of 2 modes with a count of 44.
Tests for Location: Mu0=0
Test -Statistic- -----p Value------
Student’s t t -2.13212 Pr > |t| 0.0340
Sign M -3 Pr >= |M| 0.7439
Signed Rank S -2757.5 Pr >= |S| 0.0074
Quantiles (Definition 5)
Quantile Estimate
100% Max 1.231996
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 155
99% 1.231996
95% 1.231996
90% 1.231996
75% Q3 1.138164
50% Median -0.142633
25% Q1 -1.420813
10% -2.316417
5% -3.170772
1% -3.397384
0% Min -3.397384
Extreme Observations
------Lowest----- ----Highest----
Value Obs Value Obs
-3.39738 232 1.232 209
-3.39738 183 1.232 215
-3.39738 126 1.232 225
-3.39738 116 1.232 228
-3.39738 80 1.232 233
6. Likelihood Ratio Test for Random-Slopes and Treatment
MML AGQ 11 / Slopes
The NLMIXED Procedure
Specifications
Data Set M.ARMD
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b1 b2
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 867
Observations Not Used 93
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 6
Quadrature Points 11
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 156
Parameters
beta0 beta1 beta2 sigmab1 sigmab2 rho NegLogLike
0.567 0.0098 0.0133 2 1 -0.4 544.043791
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 6 509.742775 34.30102 84.0385 -862.232
2 10 498.18797 11.55481 99.93202 -1148.82
3 11 492.660684 5.527286 258.3582 -87.4619
4 13 473.505389 19.1553 310.3252 -208.164
5 15 460.92047 12.58492 149.7404 -338.749
6 18 454.404707 6.515763 27.99769 -39.3351
7 22 452.922877 1.48183 93.24139 -13.0028
8 24 447.074267 5.84861 62.17724 -26.2715
9 26 444.280983 2.793284 39.7117 -7.89304
10 28 443.944389 0.336594 18.89171 -0.91955
11 30 443.865729 0.078661 7.777303 -0.25302
12 32 443.837887 0.027842 7.197167 -0.04727
13 33 443.8235 0.014387 11.41167 -0.02545
14 34 443.799149 0.024351 3.130796 -0.04482
15 36 443.794579 0.00457 0.580312 -0.00868
16 38 443.794463 0.000115 0.106616 -0.00016
17 40 443.794458 5.048E-6 0.017819 -0.00001
18 42 443.794458 9.262E-8 0.000285 -1.85E-7
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 887.6
AIC (smaller is better) 899.6
AICC (smaller is better) 899.7
BIC (smaller is better) 920.3
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta0 0.7705 0.2916 232 2.64 0.0088 0.05 0.1960 1.3450 1.239E-6
beta1 0.05198 0.01965 232 2.64 0.0087 0.05 0.01326 0.09070 -0.00023
beta2 0.02617 0.01986 232 1.32 0.1890 0.05 -0.01297 0.06530 0.000285
sigmab1 2.3409 0.4453 232 5.26 <.0001 0.05 1.4635 3.2183 -0.00001
sigmab2 0.08663 0.03030 232 2.86 0.0046 0.05 0.02694 0.1463 0.000176
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 157
rho -0.06296 0.2146 232 -0.29 0.7695 0.05 -0.4858 0.3599 9.422E-6
LRT for Random-Slopes
Obs L01 df pval
1 10.9813 2 0.00412509
MML AGQ 21
The NLMIXED Procedure
Specifications
Data Set M.ARMD
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 867
Observations Not Used 93
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 4
Quadrature Points 21
Parameters
beta0 beta1 beta2 sigmab NegLogLike
0.567 0.0098 0.0133 2 456.839858
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 451.983229 4.856629 124.8697 -5660.5
2 7 451.757196 0.226033 147.9445 -34.8476
3 9 450.235473 1.521723 148.7505 -1.52714
4 11 449.374956 0.860517 13.6623 -0.74259
5 13 449.33067 0.044286 13.67166 -0.04632
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 158
6 14 449.307713 0.022957 12.29118 -0.02598
7 16 449.295735 0.011978 0.151947 -0.02314
8 18 449.295733 1.798E-6 0.007548 -3.54E-6
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 898.6
AIC (smaller is better) 906.6
AICC (smaller is better) 906.6
BIC (smaller is better) 920.4
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta0 1.0170 0.2273 233 4.47 <.0001 0.05 0.5692 1.4648 0.000546
beta1 0.02113 0.007314 233 2.89 0.0042 0.05 0.006718 0.03554 0.007548
beta2 0.01089 0.01019 233 1.07 0.2865 0.05 -0.00919 0.03097 0.002414
sigmab 2.1850 0.2500 233 8.74 <.0001 0.05 1.6924 2.6776 -0.0003
MML AGQ 21 / Slopes
The NLMIXED Procedure
Specifications
Data Set M.ARMD
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b1 b2
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 867
Observations Not Used 93
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 6
Quadrature Points 21
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 159
Parameters
beta0 beta1 beta2 sigmab1 sigmab2 rho NegLogLike
0.567 0.0098 0.0133 2 1 -0.4 544.645228
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 6 508.814127 35.8311 76.91253 -888.317
2 11 494.473049 14.34108 115.9135 -846.425
3 12 489.205057 5.267992 352.7759 -100.889
4 13 474.066284 15.13877 403.8682 -245.292
5 14 469.060912 5.005372 252.3568 -473.345
6 15 464.554016 4.506896 95.06775 -173.992
7 17 451.325728 13.22829 89.90595 -23.1047
8 20 445.896149 5.429579 97.98775 -10.7319
9 23 444.772811 1.123338 75.11573 -4.00958
10 25 444.224114 0.548697 46.71996 -1.83776
11 27 444.060575 0.163539 29.85323 -0.62587
12 29 443.975696 0.084879 10.21039 -0.18815
13 31 443.941786 0.03391 2.386618 -0.06049
14 32 443.926112 0.015674 7.71936 -0.02338
15 33 443.905028 0.021084 1.73063 -0.03699
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
16 35 443.902974 0.002054 0.296542 -0.00418
17 37 443.902656 0.000318 0.090368 -0.00065
18 39 443.902654 1.757E-6 0.004427 -3.63E-6
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 887.8
AIC (smaller is better) 899.8
AICC (smaller is better) 899.9
BIC (smaller is better) 920.5
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta0 0.7860 0.2863 232 2.75 0.0065 0.05 0.2218 1.3501 -0.00004
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 160
beta1 0.04966 0.01781 232 2.79 0.0057 0.05 0.01457 0.08475 0.004427
beta2 0.02492 0.01908 232 1.31 0.1929 0.05 -0.01268 0.06252 0.001834
sigmab1 2.3139 0.4379 232 5.28 <.0001 0.05 1.4512 3.1766 0.00009
sigmab2 0.07987 0.02266 232 3.52 0.0005 0.05 0.03522 0.1245 0.000881
rho -0.03661 0.2206 232 -0.17 0.8683 0.05 -0.4711 0.3979 0.00001
LRT for Random-Slopes with AGQ 21
Obs L01 df pval
1 10.7862 2 0.0045479
MML AGQ 21 / No Treatment
The NLMIXED Procedure
Specifications
Data Set M.ARMD
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b1 b2
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 867
Observations Not Used 93
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 5
Quadrature Points 21
Parameters
beta0 beta1 sigmab1 sigmab2 rho NegLogLike
0.567 0.0098 2 1 -0.4 545.246331
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 2 518.676407 26.56992 211.711 -745.686
2 6 499.702865 18.97354 375.7346 -207.13
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 161
3 11 452.212061 47.4908 33.28212 -1135.49
4 14 451.778791 0.433269 13.0378 -28.5472
5 16 447.578188 4.200603 142.6708 -17.2894
6 18 445.641089 1.9371 34.58276 -7.15164
7 20 445.043715 0.597373 21.19192 -1.04116
8 22 444.929054 0.114661 8.070474 -0.3141
9 24 444.888969 0.040086 3.650612 -0.0484
10 25 444.843874 0.045095 8.507939 -0.03002
11 27 444.840645 0.003229 0.677189 -0.00692
12 29 444.840612 0.000033 0.023544 -0.00007
13 31 444.840611 8.09E-7 0.010103 -1.78E-6
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 889.7
AIC (smaller is better) 899.7
AICC (smaller is better) 899.8
BIC (smaller is better) 917.0
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta0 0.8148 0.2867 232 2.84 0.0049 0.05 0.2499 1.3798 0.000088
beta1 0.05914 0.01790 232 3.30 0.0011 0.05 0.02387 0.09440 -0.0101
sigmab1 2.3359 0.4384 232 5.33 <.0001 0.05 1.4721 3.1997 -0.00003
sigmab2 0.07712 0.02241 232 3.44 0.0007 0.05 0.03297 0.1213 0.004551
rho -0.02278 0.2275 232 -0.10 0.9203 0.05 -0.4709 0.4254 0.000635
LRT for Treatment
Obs L01 df pval
1 1.87591 1 0.17080
7. Marginal Average Evolutions
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 162
Figure 4.1: Fitted marginal average evolutions under the random-slopes model. Treatment A corresponds toplacebo and B to active treatment.
8. Test for treatment difference at week 52.
Initial Values
The GENMOD Procedure
Model Information
Data Set M.ARMD52
Distribution Binomial
Link Function Logit
Dependent Variable bindif
Number of Observations Read 960
Number of Observations Used 867
Number of Events 615
Number of Trials 867
Missing Values 93
Response Profile
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 163
Ordered Total
Value bindif Frequency
1 1 615
2 0 252
PROC GENMOD is modeling the probability that bindif=’1’.
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 860 1023.0599 1.1896
Scaled Deviance 860 1023.0599 1.1896
Pearson Chi-Square 860 867.0000 1.0081
Scaled Pearson X2 860 867.0000 1.0081
Log Likelihood -511.5299
Algorithm converged.
Analysis Of Parameter Estimates
Standard Wald 95% Confidence Chi-
Parameter DF Estimate Error Limits Square Pr > ChiSq
Intercept 1 0.7522 0.1410 0.4758 1.0285 28.46 <.0001
time12 1 -0.3538 0.2355 -0.8153 0.1077 2.26 0.1329
time24 1 -0.1253 0.2434 -0.6023 0.3517 0.27 0.6067
time52 1 0.5190 0.2749 -0.0197 1.0578 3.57 0.0590
time12*treat 1 0.6288 0.2870 0.0662 1.1914 4.80 0.0285
time24*treat 1 0.4457 0.3016 -0.1454 1.0369 2.18 0.1394
time52*treat 1 0.4205 0.3745 -0.3136 1.1545 1.26 0.2616
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
Time as factor
The NLMIXED Procedure
Specifications
Data Set M.ARMD52
Dependent Variable bindif
Distribution for Dependent Variable Binary
Random Effects b
Distribution for Random Effects Normal
Subject Variable subject
Optimization Technique Dual Quasi-Newton
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 164
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 867
Observations Not Used 93
Total Observations 960
Subjects 234
Max Obs Per Subject 4
Parameters 8
Quadrature Points 21
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 2 447.178432 6.839458 4.112587 -141.884
2 4 446.466303 0.712128 1.599455 -8.53051
3 6 446.366192 0.100112 1.21234 -0.78402
4 7 446.330371 0.035821 1.361423 -0.36477
5 8 446.290535 0.039835 0.403971 -0.31919
6 10 446.26413 0.026406 0.041269 -0.06805
7 12 446.263779 0.000351 0.012186 -0.0006
8 14 446.263727 0.000052 0.006959 -0.0001
9 16 446.263722 5.034E-6 0.002377 -0.00001
10 18 446.263721 5.587E-7 0.000314 -1.12E-6
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 892.5
AIC (smaller is better) 908.5
AICC (smaller is better) 908.7
BIC (smaller is better) 936.2
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
beta0 1.3271 0.2559 233 5.19 <.0001 0.05 0.8230 1.8313 0.000314
beta1 -0.5212 0.3333 233 -1.56 0.1193 0.05 -1.1779 0.1355 0.000149
beta2 -0.1247 0.3412 233 -0.37 0.7152 0.05 -0.7970 0.5476 -0.00015
beta3 0.9495 0.3803 233 2.50 0.0132 0.05 0.2002 1.6987 0.000232
beta4 0.8586 0.4451 233 1.93 0.0550 0.05 -0.01837 1.7356 0.000134
beta5 0.5561 0.4622 233 1.20 0.2302 0.05 -0.3546 1.4668 -0.00013
beta6 0.4982 0.5413 233 0.92 0.3583 0.05 -0.5682 1.5646 0.000099
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 165
sigmab 2.1981 0.2513 233 8.75 <.0001 0.05 1.7030 2.6931 -0.00003
Additional Estimates
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
MrgTrEff 0.3048 0.3316 233 0.92 0.3589 0.05 -0.3485 0.9582
4.3.3 Discussion
1. Exploring incomplete data.
The total number of subjects equals 240, meaning that a substantial portion of the data is subject tomissingness. Both intermittent missingness as well as dropout occurs. An overview is given in Table 4.3.Thus, 78.33% of the profiles are complete, while 18.33% exhibit monotone missingness. Out of the latter
Table 4.3: Age Related Macular Degeneration Trial. Overview of missingness patterns and the frequencies withwhich they occur. ‘O’ indicates observed and ‘M’ indicates missing.
Measurement occasion
4 wks 12 wks 24 wks 52 wks Number %
Completers
O O O O 188 78.33
Dropouts
O O O M 24 10.00
O O M M 8 3.33
O M M M 6 2.50
M M M M 6 2.50
Non-monotone missingness
O O M O 4 1.67
O M M O 1 0.42
M O O O 2 0.83
M O M M 1 0.42
group, 2.5% or 6 subjects have no follow-up measurements. The remaining 3.33%, representing 8 subjects,have intermittent missing values. Although the group of dropouts is of considerable magnitude, the ones withintermittent missingness is much smaller. Nevertheless, it is cautious to include all into the analyses. Thisis certainly possible for direct likelihood analyses and for standard GEE (generalized estimating equations),but WGEE is more complicated in this respect. One solution is to monotonize the missingness patterns bymeans of multiple imputation and then conduct WGEE.
2. GEE and WGEE analyses.
We perform analyses on the completers only (CC), on the LOCF imputed data, as well as on the observeddata. In all cases, standard GEE, and linearization-based GEE (an alternative to standard GEE; the detailsare not important at this stage) will be considered. For the observed, partially incomplete data, GEEis supplemented with WGEE. Further, a random-intercepts GLMM (generalized linear mixed model) isconsidered, based on both PQL (penalized quasi-likelihood) and numerical integration. The GEE analyses
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 166
are reported in Table 4.4 and the random-effects models in Table 4.6. In all cases, we use the logit link.For GEE, a working exchangeable correlation matrix is considered. The model has four intercepts andfour treatment effects. The advantage of having separate treatment effects at each time is that particularattention can be given at the treatment effect assessment at the last planned measurement occasion, i.e.,after one year.
Table 4.4: Age Related Macular Degeneration Trial. Parameter estimates (model-based standard errors; empir-ically corrected standard errors) for the marginal models: standard and linearization-based GEE on the CC andLOCF population, and on the observed data. In the latter case, also WGEE is used.
Effect Par. CC LOCF Observed data
Unweighted WGEE
Standard GEE
Int.4 β11 -1.01(0.24;0.24) -0.87(0.20;0.21) -0.87(0.21;0.21) -0.98(0.10;0.44)
Int.12 β21 -0.89(0.24;0.24) -0.97(0.21;0.21) -1.01(0.21;0.21) -1.78(0.15;0.38)
Int.24 β31 -1.13(0.25;0.25) -1.05(0.21;0.21) -1.07(0.22;0.22) -1.11(0.15;0.33)
Int.52 β41 -1.64(0.29;0.29) -1.51(0.24;0.24) -1.71(0.29;0.29) -1.72(0.25;0.39)
Tr.4 β12 0.40(0.32;0.32) 0.22(0.28;0.28) 0.22(0.28;0.28) 0.80(0.15;0.67)
Tr.12 β22 0.49(0.31;0.31) 0.55(0.28;0.28) 0.61(0.29;0.29) 1.87(0.19;0.61)
Tr.24 β32 0.48(0.33;0.33) 0.42(0.29;0.29) 0.44(0.30;0.30) 0.73(0.20;0.52)
Tr.52 β42 0.40(0.38;0.38) 0.34(0.32;0.32) 0.44(0.37;0.37) 0.74(0.31;0.52)
Corr. ρ 0.39 0.44 0.39 0.33
Linearization-based GEE
Int.4 β11 -1.01(0.24;0.24) -0.87(0.21;0.21) -0.87(0.21;0.21) -0.98(0.18;0.44)
Int.12 β21 -0.89(0.24;0.24) -0.97(0.21;0.21) -1.01(0.22;0.21) -1.78(0.26;0.42)
Int.24 β31 -1.13(0.25;0.25) -1.05(0.21;0.21) -1.07(0.23;0.22) -1.19(0.25;0.38)
Int.52 β41 -1.64(0.29;0.29) -1.51(0.24;0.24) -1.71(0.29;0.29) -1.81(0.39;0.48)
Tr.4 β12 0.40(0.32;0.32) 0.22(0.28;0.28) 0.22(0.29;0.29) 0.80(0.26;0.67)
Tr.12 β22 0.49(0.31;0.31) 0.55(0.28;0.28) 0.61(0.28;0.29) 1.85(0.32;0.64)
Tr.24 β32 0.48(0.33;0.33) 0.42(0.29;0.29) 0.44(0.30;0.30) 0.98(0.33;0.60)
Tr.52 β42 0.40(0.38;0.38) 0.34(0.32;0.32) 0.44(0.37;0.37) 0.97(0.49;0.65)
σ2 0.62 0.57 0.62 1.29
τ2 0.39 0.44 0.39 1.85
Corr. ρ 0.39 0.44 0.39 0.59
Note also that the treatment effect under LOCF, especially at 12 weeks and after 1 year, is biased downwardin comparison to the GEE analyses. To properly use the information in the missingness process, WGEE canbe used. To this end, a logistic regression for dropout, given covariates and previous outcomes, needs tobe fitted. Parameter estimates and standard errors are given in Table 4.5. Intermittent missingness will beignored. Covariates of importance are treatment assignment, the level of lesions at baseline (a four-pointcategorical variable, for which three dummies are needed), and time at which dropout occurs. For the lattercovariates, there are three levels, since dropout can occur at times 2, 3, or 4. Hence, two dummy variablesare included. Finally, the previous outcome does not have a significant impact, but will be kept in the modelnevertheless.
In spite of there being no strong evidence for MAR, the results between GEE and WGEE differ quite a bit.It is noteworthy that at 12 weeks, a treatment effect is observed with WGEE which goes unnoticed with theother marginal analyses. This finding is mildly confirmed by the random-intercept model, when the data asobserved are used.
3. Random-intercepts model.
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 167
Table 4.5: Age Related Macular Degeneration Trial. Parameter estimates (standard errors) for a logistic regressionmodel to describe dropout.
Effect Parameter Estimate (s.e.)
Intercept ψ0 0.14 (0.49)
Previous outcome ψ1 0.04 (0.38)
Treatment ψ2 -0.86 (0.37)
Lesion level 1 ψ31 -1.85 (0.49)
Lesion level 2 ψ32 -1.91 (0.52)
Lesion level 3 ψ33 -2.80 (0.72)
Time 2 ψ41 -1.75 (0.49)
Time 3 ψ42 -1.38 (0.44)
The results for the random-intercept models are given in Table 4.6. We observe the usual downward biasin the PQL versus numerical integration analysis, as well as the usual relationship between the marginalparameters of Table 4.4 and their random-effects counterparts. Note also that the random-interceptsvariance is largest under LOCF, underscoring again that this method artificially increases the associationbetween measurements on the same subject.
4. Multiple imputation.
One complication with WGEE is that the calculation of the weights is difficult with non-monotone missing-ness. Standard GEE on the incomplete data is valid only when the missing data are MCAR. Precisely here,multiple imputation is an appealing alternative.
The binary indicators were created by dichotomizing the continuous visual acuity outcomes, as negativeversus non-negative. The continuous outcomes were defined as the change from baseline in number of lettersread. Therefore, multiple imputation could start from the continuous outcomes. Ten multiply-imputeddatasets were created. The imputation model included, apart from the four continuous outcomes variables,also the four-point categorical variable ‘lesions.’ For simplicity, the latter was treated as continuous. Separateimputations were conducted for each of the two treatment groups. These choices imply that the imputedvalues depend on lesions and treatment assignment, and hence analysis models that include one or both ofthese effects are proper in the sense of Rubin (1987). This means, broadly speaking, that the model usedfor imputation should include all relationships that later will be considered in the analysis and inferencetasks. The added advantage of including ‘lesions’ into the imputation model, is that even individuals forwhich none of the four follow-up measurements are available, are still imputed. The MCMC method wasused, with EM starting values, and a single chain for all imputations.
Upon imputation, the same marginal GEE and random-intercept models as before were fitted in the analysistask. Results from the inference task are reported in Table 4.7.
The parameter estimates and standard errors are very similar to their counterparts in Table 4.4 and 4.6. Ofcourse, in the GEE case, there is no direct counterpart, since the WGEE method is different from GEE aftermultiple imputation, even though both are valid under MAR. However, in particular the similarity betweenthe direct likelihood method (bottom right column of Table 4.6) is clear, with only a minor deviation inestimate for the treatment effect after 1 year.
5. PQL versus MQL
Small fluctuations in the fixed-effects estimates are observed between PQL and MQL methods. However,greater differences are observed for the variance component for which MQL and ML methods seem tounderestimate it.
6. Gaussian Quadrature
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 168
Table 4.6: Age Related Macular Degeneration Trial. Parameter estimates (standard errors) for the random-intercept models: PQL and numerical-integration based fits on the CC and LOCF population, and on the observeddata (direct-likelihood).
Effect Parameter CC LOCF Direct lik.
PQL
Int.4 β11 -1.19(0.31) -1.05(0.28) -1.00(0.26)
Int.12 β21 -1.05(0.31) -1.18(0.28) -1.19(0.28)
Int.24 β31 -1.35(0.32) -1.30(0.28) -1.26(0.29)
Int.52 β41 -1.97(0.36) -1.89(0.31) -2.02(0.35)
Trt.4 β12 0.45(0.42) 0.24(0.39) 0.22(0.37)
Trt.12 β22 0.58(0.41) 0.68(0.38) 0.71(0.37)
Trt.24 β32 0.55(0.42) 0.50(0.39) 0.49(0.39)
Trt.52 β42 0.44(0.47) 0.39(0.42) 0.46(0.46)
R.I. s.d. τ 1.42(0.14) 1.53(0.13) 1.40(0.13)
R.I. var. τ2 2.03(0.39) 2.34(0.39) 1.95(0.35)
Numerical integration
Int.4 β11 -1.73(0.42) -1.63(0.39) -1.50(0.36)
Int.12 β21 -1.53(0.41) -1.80(0.39) -1.73(0.37)
Int.24 β31 -1.93(0.43) -1.96(0.40) -1.83(0.39)
Int.52 β41 -2.74(0.48) -2.76(0.44) -2.85(0.47)
Trt.4 β12 0.64(0.54) 0.38(0.52) 0.34(0.48)
Trt.12 β22 0.81(0.53) 0.98(0.52) 1.00(0.49)
Trt.24 β32 0.77(0.55) 0.74(0.52) 0.69(0.50)
Trt.52 β42 0.60(0.59) 0.57(0.56) 0.64(0.58)
R.I. s.d. τ 2.19(0.27) 2.47(0.27) 2.20(0.25)
R.I. var. τ2 4.80(1.17) 6.08(1.32) 4.83(1.11)
The Gaussian quadrature parameter estimates seem stable except from the Laplace and AGQ 5 cases.Comparing these results with the PQL and MQL methods we observe some downwards bias for almost allthe parameters, and especially for σ2
b . This is expected due to the small number of repeated measurementper subject and the fact that the variance estimate for the random-effect is far from zero.
7. Hypothesis Testing
The likelihood ratio tests suggest that first the random-slopes model provide a better fit to the data, andsecond that evolutions in time are not statistically different for the two treatment groups. Note howeverthat the test for random-slopes is on the boundary of the parameter space for the variance term.
8. Marginal Average Evolutions
The marginal average evolutions under the final model are depicted in Figure 4.1. The probability of ‘bindif= 1’ seems greater for the active treatment even though this difference is not statistically significant.
9. Treatment effect at week 52
The test for ‘Time52*Treatment’ regression coefficient suggests a statistically nonsignificant differenceat week 52 for the two treatment groups. Note however, that this test refers to the conditional on therandom-effects treatment difference and not to the marginal one. In order to test for the marginal treatmentdifference at week 52 we use the approximate formula βM = βRE/
√
c2σ2b + 1, where c2 = [16
√3/(15π)]2 ≈
0.345843. This leads to the same conclusion with a similar p-value.
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 169
Table 4.7: Age Related Macular Degeneration Trial. Parameter estimates (standard errors) for the standard GEEand numerical-integration based random-intercept models, after generating 10 multiple imputations.
Effect Par. GEE GLMM
Int.4 β11 -0.84(0.20) -1.46(0.36)
Int.12 β21 -1.02(0.22) -1.75(0.38)
Int.24 β31 -1.07(0.23) -1.83(0.38)
Int.52 β41 -1.61(0.27) -2.69(0.45)
Trt.4 β12 0.21(0.28) 0.32(0.48)
Trt.12 β22 0.60(0.29) 0.99(0.49)
Trt.24 β32 0.43(0.30) 0.67(0.51)
Trt.52 β42 0.37(0.35) 0.52(0.56)
R.I. s.d. τ 2.20(0.26)
R.I. var. τ2 4.85(1.13)
Table 4.8: Parameter estimates (standard error) under PQL and MQL methods using either REML or ML.
PQL (REML) PQL (ML) MQL (REML) MQL (ML)
Intercept 0.664(0.159) 0.663(0.159) 0.568(0.140) 0.568(0.140)
Time 0.015(0.006) 0.015(0.006) 0.011(0.005) 0.011(0.005)
Time*Treatment 0.010(0.008) 0.010(0.008) 0.010(0.007) 0.010(0.007)
σ2b 1.911(0.342) 1.881(0.338) 1.412(0.255) 1.396(0.252)
Table 4.9: Parameter estimates (standard error) and log-likelihood values using Gaussian and adaptive GaussianQuadrature.
GQ 25 GQ 51 Laplace ≡ AGQ 1 AGQ 5 AGQ 11
Intercept 1.017(0.227) 1.017(0.227) 1.038(0.226) 0.994(0.221) 1.018(0.228)
Time 0.021(0.007) 0.021(0.007) 0.020(0.007) 0.021(0.007) 0.021(0.007)
Time*Treatment 0.011(0.010) 0.011(0.010) 0.011(0.010) 0.011(0.010) 0.011(0.010)
σ2b 4.780(1.098) 4.774(1.093) 4.220(0.978) 4.508(0.989) 4.785(1.099)
log-Lik −449.2921 −449.2957 −454.0558 −449.8744 −449.2851
Table 4.10: Likelihood ratio test for random-slopes and treatment effect.
LRT df p-value
random-slopes AGQ 11 10.98 2 0.0041
random-slopes AGQ 21 10.79 2 0.0045
treatment 1.88 1 0.1708
DATASET 4. AGE-RELATED MACULAR DEGENERATION STUDY 170
Table 4.11: Parameter estimates, standard errors and p-values under a GLMM treating time as factor.
Value Std. Error p-value
Intercept 1.327 0.256 < 0.0001
Time12 −0.521 0.333 0.1193
Time24 −0.125 0.341 0.7152
Time52 0.950 0.380 0.0132
Time12*Treatment 0.859 0.445 0.0550
Time24*Treatment 0.556 0.462 0.2302
Time52*Treatment 0.498 0.541 0.3583
σb 2.198 0.251 −Marginal Treat Effect W52 0.305 0.332 0.3589
Dataset 5
Blood Pressure Data
5.1 The Data
We consider data reported by Hand et al . (1994), data set #72. For 15 patients with moderate essential (unknowncause) hypertension, the supine (measured while patient is lying down) systolic and diastolic blood pressure wasmeasured immediately before and 2 hours after taking the drug captopril. The individual profiles are shown inFigure 5.1. The objective of the analysis is to investigate the effect of treatment on both responses. These datahave been analyzed in Verbeke and Molenberhs (1997, Ch. 4.3; 2000, Ch. 24.1). We refer to these text for anintroduction and an overview of the models that have been fitted. For example, the final model considered is
data blood;
set blood;
slope = (time = ’after’);
intsys = (meas = ’systolic’);
run;
proc mixed data = blood covtest;
class time meas id;
model bp = meas*time / noint s;
random intercept intsys slope / type = un(1) subject = id;
estimate ’trt_sys’ meas*time 0 -1 0 1 / cl alpha = 0.05;
estimate ’trt_dia’ meas*time -1 0 1 0 / cl alpha = 0.05;
Figure 5.1: Blood Pressure Data. Systolic and diastolic blood pressure in patients with moderate essential
hypertension, immediately before and 2 hours after taking captopril.
171
DATASET 5. BLOOD PRESSURE DATA 172
contrast ’trt_sys = 2xtrt_dia’ meas*time 2 -1 -2 1;
run;
5.2 Questions
While there are only 4 measurements per subject, there is a double structure to the data:
Bivariate structure: Both systolic and diastolic blood pressure are recorded.
Repeated measures: Both of these measures are taken at two well defined points in time: immediately beforeand 2 hours after taking captopril.
Some questions:
• Fit models which explicitly make use of PROC MIXED features for such multivariate repeated measures.
• Compare the covariance structures:
– unstructured; in the original model (Verbeke and Molenberghs 1997, 2000);
– in meaningful multivariate repeated measure covariance structures.
• What is the impact on the treatment effect assessments ?
5.2.1 Dataset
The dataset is BLOOD.SAS7BDAT.
5.3 Elements of Solution
5.3.1 Basic Program
libname m ’c:\bartsas\gent’;
data m.blood1;
set m.blood;
slope = (time = ’after’);
intsys = (meas = ’systolic’);
run;
proc print data=m.blood1;
title ’Blood Pressure Data’;
run;
proc mixed data = m.blood1 covtest;
title ’Model from Verbeke-Molenberghs’;
class time meas id;
DATASET 5. BLOOD PRESSURE DATA 173
model bp = meas*time / noint s;
random intercept intsys slope / type = un(1) subject = id v;
estimate ’trt_sys’ meas*time 0 -1 0 1 / cl alpha = 0.05;
estimate ’trt_dia’ meas*time -1 0 1 0 / cl alpha = 0.05;
run;
proc mixed data = m.blood1 covtest;
title ’Model 1: 4x4 unstructured covariance matrix’;
class time meas id;
model bp = meas*time / noint s;
repeated / type=un subject = id r;
estimate ’trt_sys’ meas*time 0 -1 0 1 / cl alpha = 0.05;
estimate ’trt_dia’ meas*time -1 0 1 0 / cl alpha = 0.05;
run;
proc mixed data = m.blood1 covtest;
title ’Model 2: unstructured-by-unstructured’;
class time meas id;
model bp = meas*time / noint s;
repeated meas time / type=un@un subject = id r;
estimate ’trt_sys’ meas*time 0 -1 0 1 / cl alpha = 0.05;
estimate ’trt_dia’ meas*time -1 0 1 0 / cl alpha = 0.05;
run;
proc mixed data = m.blood1 covtest;
title ’Model 3: unstructured-by-compound symmetry’;
class time meas id;
model bp = meas*time / noint s;
repeated meas time / type=un@cs subject = id r;
estimate ’trt_sys’ meas*time 0 -1 0 1 / cl alpha = 0.05;
estimate ’trt_dia’ meas*time -1 0 1 0 / cl alpha = 0.05;
run;
5.3.2 Raw Output
Blood Pressure Data 12:17 Sunday, April 23, 2000 434
OBS ID BP MEAS TIME SLOPE INTSYS
1 1 210 systolic before 0 1
2 2 169 systolic before 0 1
3 3 187 systolic before 0 1
4 4 160 systolic before 0 1
5 5 167 systolic before 0 1
6 6 176 systolic before 0 1
7 7 185 systolic before 0 1
8 8 206 systolic before 0 1
9 9 173 systolic before 0 1
10 10 146 systolic before 0 1
11 11 174 systolic before 0 1
12 12 201 systolic before 0 1
13 13 198 systolic before 0 1
14 14 148 systolic before 0 1
15 15 154 systolic before 0 1
DATASET 5. BLOOD PRESSURE DATA 174
16 1 201 systolic after 1 1
17 2 165 systolic after 1 1
18 3 166 systolic after 1 1
19 4 157 systolic after 1 1
20 5 147 systolic after 1 1
21 6 145 systolic after 1 1
22 7 168 systolic after 1 1
23 8 180 systolic after 1 1
24 9 147 systolic after 1 1
25 10 136 systolic after 1 1
26 11 151 systolic after 1 1
27 12 168 systolic after 1 1
28 13 179 systolic after 1 1
29 14 129 systolic after 1 1
30 15 131 systolic after 1 1
31 1 130 diastolic before 0 0
32 2 122 diastolic before 0 0
33 3 124 diastolic before 0 0
34 4 104 diastolic before 0 0
35 5 112 diastolic before 0 0
36 6 101 diastolic before 0 0
37 7 121 diastolic before 0 0
38 8 124 diastolic before 0 0
39 9 115 diastolic before 0 0
40 10 102 diastolic before 0 0
41 11 98 diastolic before 0 0
42 12 119 diastolic before 0 0
43 13 106 diastolic before 0 0
44 14 107 diastolic before 0 0
45 15 100 diastolic before 0 0
46 1 125 diastolic after 1 0
47 2 121 diastolic after 1 0
48 3 121 diastolic after 1 0
49 4 106 diastolic after 1 0
50 5 101 diastolic after 1 0
51 6 85 diastolic after 1 0
52 7 98 diastolic after 1 0
53 8 105 diastolic after 1 0
54 9 103 diastolic after 1 0
55 10 98 diastolic after 1 0
56 11 90 diastolic after 1 0
57 12 98 diastolic after 1 0
58 13 110 diastolic after 1 0
59 14 103 diastolic after 1 0
60 15 82 diastolic after 1 0
Model from Verbeke-Molenberghs 436
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TIME 2 after before
MEAS 2 diastolic systolic
ID 15 1 2 3 4 5 6 7 8 9 10 11 12 13
DATASET 5. BLOOD PRESSURE DATA 175
14 15
REML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 380.87904251
1 3 329.43913763 0.00019315
2 2 325.72780080 0.00008744
3 2 322.33035886 0.00772996
4 2 321.73878311 0.00106566
5 1 321.53994376 0.00009633
6 1 321.52346568 0.00000105
7 1 321.52329606 0.00000000
Convergence criteria met.
V Matrix for ID 1
Row COL1 COL2 COL3 COL4
1 323.99541234 311.13299395 95.40469590 95.40469590
2 311.13299395 376.04620370 95.40469590 147.45548726
3 95.40469590 95.40469590 108.26711430 95.40469590
4 95.40469590 147.45548726 95.40469590 160.31790566
Covariance Parameter Estimates (REML)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
UN(1,1) ID 95.40469590 39.45381687 2.42 0.0156
UN(2,1) ID 0.00000000 . . .
UN(2,2) ID 215.72829804 86.31500453 2.50 0.0124
UN(3,1) ID 0.00000000 . . .
UN(3,2) ID 0.00000000 . . .
UN(3,3) ID 52.05079136 24.77124215 2.10 0.0356
Residual 12.86241840 4.69297016 2.74 0.0061
Model from Verbeke-Molenberghs 437
12:17 Sunday, April 23, 2000
Model Fitting Information for BP
Description Value
Observations 60.0000
Res Log Likelihood -212.222
Akaike’s Information Criterion -216.222
Schwarz’s Bayesian Criterion -220.273
-2 Res Log Likelihood 424.4444
Null Model LRT Chi-Square 59.3557
Null Model LRT DF 3.0000
Null Model LRT P-Value 0.0000
DATASET 5. BLOOD PRESSURE DATA 176
Solution for Fixed Effects
Effect TIME MEAS Estimate Std Error DF t Pr > |t|
TIME*MEAS after diastolic 103.06666667 3.26922932 14 31.53 0.0001
TIME*MEAS after systolic 158.00000000 5.00696983 14 31.56 0.0001
TIME*MEAS before diastolic 112.33333333 2.68659778 14 41.81 0.0001
TIME*MEAS before systolic 176.93333333 4.64754711 14 38.07 0.0001
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TIME*MEAS 4 14 552.98 0.0001
ESTIMATE Statement Results
Parameter Estimate Std Error DF t Pr > |t| Alpha Lower
trt_sys 18.93333333 2.27706870 14 8.31 0.0001 0.05 14.0495
trt_dia 9.26666667 2.27706870 14 4.07 0.0011 0.05 4.3828
ESTIMATE Statement Results
Upper
23.8172
14.1505
Model 1: 4x4 unstructured covariance matrix 438
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TIME 2 after before
MEAS 2 diastolic systolic
ID 15 1 2 3 4 5 6 7 8 9 10 11 12 13
14 15
REML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 380.87904251
1 1 317.17343397 0.00000000
Convergence criteria met.
R Matrix for ID 1
DATASET 5. BLOOD PRESSURE DATA 177
Row COL1 COL2 COL3 COL4
1 422.92380952 370.78571429 143.16666667 105.07619048
2 370.78571429 400.14285714 153.07142857 166.28571429
3 143.16666667 153.07142857 109.66666667 96.54761905
4 105.07619048 166.28571429 96.54761905 157.63809524
Covariance Parameter Estimates (REML)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
UN(1,1) ID 422.92380952 159.85017479 2.65 0.0082
UN(2,1) ID 370.78571429 148.01350986 2.51 0.0122
UN(2,2) ID 400.14285714 151.23978413 2.65 0.0082
UN(3,1) ID 143.16666667 69.11550317 2.07 0.0383
UN(3,2) ID 153.07142857 69.34035909 2.21 0.0273
UN(3,3) ID 109.66666667 41.45010387 2.65 0.0082
UN(4,1) ID 105.07619048 74.50307260 1.41 0.1584
UN(4,2) ID 166.28571429 80.50230547 2.07 0.0389
UN(4,3) ID 96.54761905 43.59643431 2.21 0.0268
UN(4,4) ID 157.63809524 59.58159959 2.65 0.0082
Model Fitting Information for BP
Description Value
Observations 60.0000
Res Log Likelihood -210.047
Model 1: 4x4 unstructured covariance matrix 439
12:17 Sunday, April 23, 2000
Model Fitting Information for BP
Description Value
Akaike’s Information Criterion -220.047
Schwarz’s Bayesian Criterion -230.174
-2 Res Log Likelihood 420.0945
Null Model LRT Chi-Square 63.7056
Null Model LRT DF 9.0000
Null Model LRT P-Value 0.0000
Solution for Fixed Effects
Effect TIME MEAS Estimate Std Error DF t Pr > |t|
TIME*MEAS after diastolic 103.06666667 3.24179061 15 31.79 0.0001
TIME*MEAS after systolic 158.00000000 5.16489985 15 30.59 0.0001
TIME*MEAS before diastolic 112.33333333 2.70390664 15 41.54 0.0001
TIME*MEAS before systolic 176.93333333 5.30988895 15 33.32 0.0001
Tests of Fixed Effects
DATASET 5. BLOOD PRESSURE DATA 178
Source NDF DDF Type III F Pr > F
TIME*MEAS 4 15 523.71 0.0001
ESTIMATE Statement Results
Parameter Estimate Std Error DF t Pr > |t| Alpha Lower
trt_sys 18.93333333 2.33088307 15 8.12 0.0001 0.05 13.9652
trt_dia 9.26666667 2.22425304 15 4.17 0.0008 0.05 4.5258
ESTIMATE Statement Results
Upper
23.9015
14.0075
Model 2: unstructured-by-unstructured 440
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TIME 2 after before
MEAS 2 diastolic systolic
ID 15 1 2 3 4 5 6 7 8 9 10 11 12 13
14 15
REML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 380.87904251
1 2 336.62036209 0.04601371
2 1 332.05734669 0.02325751
3 1 327.34729868 0.00540866
4 1 326.29877861 0.00078309
5 1 326.15606451 0.00003573
6 1 326.15003498 0.00000011
7 1 326.15001728 0.00000000
Convergence criteria met.
R Matrix for ID 1
Row COL1 COL2 COL3 COL4
1 322.80926185 278.31214857 145.86670785 125.75995073
2 278.31214857 348.89346798 125.75995073 157.65328811
DATASET 5. BLOOD PRESSURE DATA 179
3 145.86670785 125.75995073 162.50540747 140.10511609
4 125.75995073 157.65328811 140.10511609 175.63645743
Covariance Parameter Estimates (REML)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
MEAS UN(1,1) ID 175.63645743 61.35722200 2.86 0.0042
UN(2,1) ID 157.65328811 62.46750542 2.52 0.0116
UN(2,2) ID 348.89346798 110.45201199 3.16 0.0016
TIME UN(1,1) ID 1.00000000 . . .
UN(2,1) ID 0.79769951 0.11005599 7.25 0.0001
UN(2,2) ID 0.92523733 0.20140740 4.59 0.0001
Model 2: unstructured-by-unstructured 441
12:17 Sunday, April 23, 2000
Model Fitting Information for BP
Description Value
Observations 60.0000
Res Log Likelihood -214.536
Akaike’s Information Criterion -219.536
Schwarz’s Bayesian Criterion -224.599
-2 Res Log Likelihood 429.0711
Null Model LRT Chi-Square 54.7290
Null Model LRT DF 4.0000
Null Model LRT P-Value 0.0000
Solution for Fixed Effects
Effect TIME MEAS Estimate Std Error DF t Pr > |t|
TIME*MEAS after diastolic 103.06666667 3.42185581 41 30.12 0.0001
TIME*MEAS after systolic 158.00000000 4.82281707 41 32.76 0.0001
TIME*MEAS before diastolic 112.33333333 3.29145771 41 34.13 0.0001
TIME*MEAS before systolic 176.93333333 4.63903195 41 38.14 0.0001
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TIME*MEAS 4 41 407.02 0.0001
ESTIMATE Statement Results
Parameter Estimate Std Error DF t Pr > |t| Alpha Lower
trt_sys 18.93333333 2.76981868 41 6.84 0.0001 0.05 13.3396
trt_dia 9.26666667 1.96522488 41 4.72 0.0001 0.05 5.2978
ESTIMATE Statement Results
DATASET 5. BLOOD PRESSURE DATA 180
Upper
24.5271
13.2355
Model 3: unstructured-by-compound symmetry 442
12:17 Sunday, April 23, 2000
The MIXED Procedure
Class Level Information
Class Levels Values
TIME 2 after before
MEAS 2 diastolic systolic
ID 15 1 2 3 4 5 6 7 8 9 10 11 12 13
14 15
REML Estimation Iteration History
Iteration Evaluations Objective Criterion
0 1 380.87904251
1 2 1096.3346546 0.50771777
2 1 732.26557531 0.41020333
3 1 536.29626092 0.29326409
4 1 434.08848104 0.18179072
5 1 383.01870378 0.10026872
6 1 358.14570277 0.05382129
7 1 345.64310292 0.03255113
8 1 338.09161836 0.02500254
9 1 332.61388737 0.01656220
10 1 328.99303806 0.00915332
11 1 327.09144038 0.00345036
12 1 326.40478781 0.00066174
13 1 326.28365539 0.00003074
14 1 326.27848046 0.00000008
15 1 326.27846792 0.00000000
Convergence criteria met.
R Matrix for ID 1
Row COL1 COL2 COL3 COL4
1 333.87161924 277.27041515 153.17839611 127.21008626
2 277.27041515 333.87161924 127.21008626 153.17839611
3 153.17839611 127.21008626 172.31420485 143.10180429
4 127.21008626 153.17839611 143.10180429 172.31420485
Covariance Parameter Estimates (REML)
Cov Parm Subject Estimate Std Error Z Pr > |Z|
DATASET 5. BLOOD PRESSURE DATA 181
MEAS UN(1,1) ID 172.31420485 59.94888923 2.87 0.0040
UN(2,1) ID 153.17839611 59.46490001 2.58 0.0100
UN(2,2) ID 333.87161924 96.66914257 3.45 0.0006
TIME Corr ID 0.83047015 0.06279775 13.22 0.0001
Model 3: unstructured-by-compound symmetry 443
12:17 Sunday, April 23, 2000
Model Fitting Information for BP
Description Value
Observations 60.0000
Res Log Likelihood -214.600
Akaike’s Information Criterion -218.600
Schwarz’s Bayesian Criterion -222.650
-2 Res Log Likelihood 429.1996
Null Model LRT Chi-Square 54.6006
Null Model LRT DF 3.0000
Null Model LRT P-Value 0.0000
Solution for Fixed Effects
Effect TIME MEAS Estimate Std Error DF t Pr > |t|
TIME*MEAS after diastolic 103.06666667 3.38933823 41 30.41 0.0001
TIME*MEAS after systolic 158.00000000 4.71784993 41 33.49 0.0001
TIME*MEAS before diastolic 112.33333333 3.38933823 41 33.14 0.0001
TIME*MEAS before systolic 176.93333333 4.71784993 41 37.50 0.0001
Tests of Fixed Effects
Source NDF DDF Type III F Pr > F
TIME*MEAS 4 41 394.34 0.0001
ESTIMATE Statement Results
Parameter Estimate Std Error DF t Pr > |t| Alpha Lower
trt_sys 18.93333333 2.74714892 41 6.89 0.0001 0.05 13.3854
trt_dia 9.26666667 1.97357208 41 4.70 0.0001 0.05 5.2810
ESTIMATE Statement Results
Upper
24.4813
13.2524
DATASET 5. BLOOD PRESSURE DATA 182
5.3.3 Covariance Structures
For the original model, the covariance structure is found by adding the ‘v’ option to the RANDOM statement.For the others, the option ‘r’ is added to the REPEATED statement.
For Model 1, the unstructured covariance matrix is self-evident. For Model 2, the covariance matrix is:
322.80926185 278.31214857 145.86670785 125.75995073
278.31214857 348.89346798 125.75995073 157.65328811
145.86670785 125.75995073 162.50540747 140.10511609
125.75995073 157.65328811 140.10511609 175.63645743
.
Manipulating the estimated covariane parameters yields:
(
175.636 157.653
157.653 348.893
)
⊗
(
1.000 0.7977
0.7977 0.9252
)
=
175.63600 140.10484 157.65300 125.75980
140.10484 162.49843 125.75980 145.86056
157.65300 125.75980 348.89300 278.31195
125.75980 145.86056 278.31195 322.79580
,
which, up to reversal, is the structure provided by the ‘r’ matrix.
For Model 3, we obtain
333.87161924 277.27041515 153.17839611 127.21008626
277.27041515 333.87161924 127.21008626 153.17839611
153.17839611 127.21008626 172.31420485 143.10180429
127.21008626 153.17839611 143.10180429 172.31420485
.
Manipulating the estimated covariane parameters yields:
(
172.314 153.178
153.178 333.872
)
⊗
(
1.0000 0.8305
0.8305 1.0000
)
=
172.31400 143.10678 153.17800 127.21433
143.10678 172.31400 127.21433 153.17800
153.17800 127.21433 333.87200 277.28070
127.21433 153.17800 277.28070 333.87200
.
In contrast, the orignal random-effects model produced:
323.99541234 311.13299395 95.40469590 95.40469590
311.13299395 376.04620370 95.40469590 147.45548726
95.40469590 95.40469590 108.26711430 95.40469590
95.40469590 147.45548726 95.40469590 160.31790566
.
A fully unstructured model yields:
422.92380952 370.78571429 143.16666667 105.07619048
370.78571429 400.14285714 153.07142857 166.28571429
143.16666667 153.07142857 109.66666667 96.54761905
105.07619048 166.28571429 96.54761905 157.63809524
.
The model fitting information can be summarized as follows:
DATASET 5. BLOOD PRESSURE DATA 183
Model −2`REML df
RI + RIsys + RS, uncorrelated 424.444 4
Model 1: Unstructured 420.095 10
Model 2: Unstructured-by-unstructured 429.071 5
Model 3: Unstructured-by-compound symmetry 429.200 4
Thus, the fit of the original model is still the best one.
The effect on the assessment of treatment effect:
Model Systolic Diastolic
Original Model 18.933 (2.777) 9.267 (2.277)
Model 1 18.933 (2.331) 9.267 (2.224)
Model 2 18.933 (2.770) 9.267 (1.965)
Model 3 18.933 (2.747) 9.267 (1.974)
Dataset 6
Marital Satisfaction Data
6.1 Description of the Data
The research sample consists of married men and women participating in the longitudinal research project “Child-rearing and family in the Netherlands”. In 1990, 1995 and 2000, the same family members (wife, husband andtarget child) provided information about similar sets of measures. Families were recruited using a multi-stagesampling method. In a first stage, a sample was taken of all Dutch municipalities distinguished by regional zoneand degree of urbanization. In a second stage, a sample of children aged 9 to 16 years old was taken in theselected municipalities. The children were selected in such a way that in each city as much boys as girls and asmuch children aged 9 to 12 as aged 13 to 16 were chosen.
The data were gathered by means of structured interviews and questionnaires, completed by both the child andthe parents. In order to establish a homogeneous research group for a study on marital quality, only first marriagesin which both men and women have a Dutch nationality were selected. This selection resulted in a research groupof 647 couples in 1990, 386 couples in 1995 and 182 couples in 2000. 17 couples that didn’t participate in 1995,did participate in 2000. Data of a couple are considered when one of the two parents participated, not necessarilyboth parents.
Outcomes of Interest
Marital satisfaction is measured by the Marital Satisfaction scale of Gerris et al. (1992, 1993, 1998). For for-mulating the items, satisfaction with the relationship and/or the partner was used as the guiding principle (e.g.,“Generally, I’m dissatisfied with the relationship with my partner” or “If I could choose again, I would choosethe same partner”). The scale consists of seven 7-point Likert items, ranging from 1 = “do not agree” to 7 =“completely agree”.
The open communication scale of Gerris et al. (1992, 1993) maps out the open communicational styles of thecouple. Respondents were asked to indicate to what degree personal feelings and experiences were shared (e.g.,“I often talk to my partner about things we are both interested in” or “I often talk to my partner about personalproblems”). The open communication scale also consists of three 7-point Likert items.
The negative communication scale of Gerris et al. (1992, 1993) maps out the negative communication styles ofthe couple. Respondents were asked to indicate to what degree certain forms of negative communication arecharacteristic to their marital relationship (e.g., “My partner often blames me when we are quarrelling” or “My
184
DATASET 6. MARITAL SATISFACTION DATA 185
partner and I interrupt each other a lot when we are talking together”). The scale consists of six 7-point Likertitems.
The uniqueness and stability of these concepts were demonstrated in Van den Troost et al. (2001).
Covariates of Interest
Education was measured in response to the question “What is your highest educational level?”, using a nine-levelscale ranging from 1 = “elementary school” to 9 = “university education”. Family income was measured inresponse to the question “What is the monthly net family income (in guilders, approx. 0.45 euro)?” Seven incomegroups were distinguished: 1 = “1100–1600”, then in groups of 500 guilders, until 7 = “more than 4500”. Furthercovariates are year of birth, year of marriage, number of children and marital status of the parents of the couple.For the latter, to both husband and wife it was asked “The time you were living with your parents, they weremarried all the time?”. Response categories were 1 = “yes”, 2 = “no” and 3 = “not applicable”.
marsatCC.xls and marsatIC.xls
FAMNR : family identification number
IDNR : parent identification number
YEAR : year of interview (1990, 1995, 2000)
PARENT : parent (0=father, 1=mother)
SAT : marital satisfaction score
PCOM : open communication score
DCOM : negative communication score
CHILD : number of children
BIRTH : year of birth
EDUC : educational level
MARR : year of marriage
INCOME : income category
STATUS : marital status of the parents of the couple (1=yes, 2=no)
References
Gerris, J. R. M., Houtmans, M. J. M., Kwaaitaal-Roosen, E. M. G., Schipper, J. C., Vermulst, A. A. andJanssens, J. M. A. M. (1998) Parents, adolescents and young adults in Dutch families. A longitudinalstudy. Nijmegen: University of Nijmegen, Institute of Family Studies.
Gerris, J. R. M., Van Boxtel, D. A. A. M., Vermulst, A. A., Janssens, J. M. A. M., Van Zutphen, R. A. H. andFelling, A. J. A. (1992) Child-rearing, family relations and family processes in 1990. Nijmegen: Universityof Nijmegen, Institute of Family Studies.
DATASET 6. MARITAL SATISFACTION DATA 186
Gerris, J. R. M., Vermulst, A. A., Van Boxtel, D. A. A. M., Janssens, J. M. A. M., Van Zutphen, R. A. H. andFelling, A. J. A. (1993) Parenting in Dutch families. Nijmegen: University of Nijmegen, Institute of FamilyStudies.
Van den Troost, A., Vermulst, A. A., Gerris, J. R. M. and Matthijs, K. (2001) Meetinvariantie van huwelijk-skwaliteit en satisfactie. Leuven/Nijmegen. Onderzoeksverslag van het Departement Sociologie - afdelingGezin, Bevolking & Gezondheidszorg en Orthopedagogiek. - Gezin en Gedrag, GB/2001-13.
6.2 Questions
Part 1
1. Import the Excel datafile marsatCC.xls in SAS. Then split this dataset into two separate files, one containingonly the information for the fathers, the other containing only the information for the mothers.
2. Fit a fixed effects model, including all covariates in the dataset (be careful, some of them are continuous,others categorical). Use the unstructured covariance structure. Perform this analysis for both fathers andmothers.
3. Reduce the mean structure of the above models, until you end up with only the significant covariates.
4. Now keep this best mean structure, and reduce the covariance structure as much as possible for both models.Is it necessary to consider the heterogeneous covariance structures?
5. From now on, use the full dataset marsatCC again (father and mother together). Consider the fixed effectsyear, parent and their interaction. Simplify the covariance structure. Be careful, there are two clusteringvariables now. Therefore, the covariance structure will be more complicated.
Part 2
Consider the following binary transformation BSAT of the marital satisfaction score which equals 0 when SAT≤ 4, and 1 otherwise. In this question we are interested in the impact of the number of years married at themoment of the interview, the year of the interview, the age, education and gender of the subjects. Use the GEEmethodology to study the impact of these variables on the marital satisfaction. Consider the following points inyour analysis
• choose an appropriate covariance structure
• compare the results for males and females separately
• does the correlation between responses of members of the same family influence these results?
Part 3
1. Consider the dichotomized version of the marital satisfaction score (BSAT) as the longitudinal outcome ofinterest. Discuss a suitable random effects structure for this score.
2. Fit a mixed effects logistic regression model for BSAT, using Penalized quasi-likelihood (PQL) and Marginalquasi-likelihood (MQL) implemented by PROC GLIMMIX. Formulate the random effects structure properly,accounting for the hierarchical data structure. Assume that the mean structure consists of the main effects
DATASET 6. MARITAL SATISFACTION DATA 187
of the variables ’parent’, ’year’ (treated as categorical), ’child’, years of marriage and the interaction between’parent’ and ’year’. Observe the estimated random effects variance components. What is implied for theassumed random effects structure?
3. For the same random effects structure fit the model using adaptive Gaussian quadrature with 20 quadraturepoints implemented by PROC NLMIXED. Test whether the lower level classification factor is needed.
4. Investigate the single level random effects structure by fitting the mixed effects logistic regression modelusing PQL, MQL under both REML and ML. Compare the resulting parameter estimates.
5. For the same random effects structure, fit the same model using Gaussian quadrature.
• Fit the model using both non adaptive and adaptive Gaussian quadrature with varying number ofnodes i.e., 3, 5, 10, 20 and 50. Compare the parameter estimates and standard errors.
• Fit the model using the Laplace approximation.
6. Compare the results from the fitted models under PQL, MQL, adaptive Gauss-Hermite with 20 nodes andLaplace approximation.
7. Plot the fitted marginal evolutions for the 3 time points, i.e., 1990, 1995 and 2000, for each parent adjustingfor the covariates at their median value. Compare these marginal evolutions with the fitted evolutions forthe median parent, i.e., for the parent with bi = 0.
8. Test for the parent effect in the final model using the likelihood ratio test.
Part 4
1. Analyze the continuous response ‘sat’ using a mixed model where the mean structure includes covariates‘year’(class), ‘parent’(class) and their interaction and the covariance structure is defined as unstructured(parent) and compound symmetry (year).
(a) Perform a complete case analysis (CC)
(b) Use all available data (Direct Likelihood)
(c) Complete the data using multiple imputation (5 imputations) and analyze the completed datasets
(d) Compare and discuss the results of all analyses
2. Analyze the binary response ‘bsat’ using GEE with mean structure ‘parent year birth parent*year parent*birthbirth*year parent*birth*year’ where ‘year’and ‘parent’ are again class-variables.
(a) Perform a complete case analysis (CC)
(b) Use a weighted GEE approach where you determine the weights based on a model with ‘covariates‘parent’(class), ‘year’(class) and ‘birth’
(c) Perform an available case GEE
(d) Complete the data using multiple imputation (5 imputations) and analyze the completed datasetsusing GEE
(e) Compare and discuss the results of all analyses
3. Analyze the binary response ‘bsat’ using GLMM with mean structure ‘parent year birth parent*year par-ent*birth birth*year parent*birth*year’ where ‘year’and ‘parent’ are again class-variables
(a) Perform a complete case analysis (CC)
(b) Perform an available case analysis (Direct Likelihood)
DATASET 6. MARITAL SATISFACTION DATA 188
6.3 Elements of Solution
6.3.1 Programs
Part 1
1. Splitting in separate datasets for father and mother:
data father;
set marital;
where parent=0;
run;
data mother;
set marital;
where parent=1;
run;
2. Full model with unstructured mean and covariance structure (for both datasets):
proc mixed data=father method=ml;
class year status;
model sat = year child birth educ marr income status / solution noint;
repeated year / type=un subject=idnr;
run;
proc mixed data=mother method=ml;
class year status;
model sat = year child birth educ marr income status / solution noint;
repeated year / type=un subject=idnr;
run;
3. Final model after reducing mean structure (for both datasets):
proc mixed data=father method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=un subject=idnr;
run;
proc mixed data=mother method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=un subject=idnr;
run;
4. Reducing the covariance structure (for both datasets):
proc mixed data=father method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=un(2) subject=idnr;
run;
DATASET 6. MARITAL SATISFACTION DATA 189
proc mixed data=father method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=arh(1) subject=idnr;
run;
proc mixed data=father method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=csh subject=idnr;
run;
proc mixed data=father method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=toeph subject=idnr;
run;
proc mixed data=father method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=cs subject=idnr;
run;
proc mixed data=mother method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=un(2) subject=idnr;
run;
proc mixed data=mother method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=arh(1) subject=idnr;
run;
proc mixed data=mother method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=csh subject=idnr;
run;
proc mixed data=mother method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=toeph subject=idnr;
run;
proc mixed data=mother method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=cs subject=idnr;
run;
DATASET 6. MARITAL SATISFACTION DATA 190
proc mixed data=mother method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=ar(1) subject=idnr;
run;
proc mixed data=mother method=ml;
class year status;
model sat = year / solution noint;
repeated year / type=simple subject=idnr;
run;
5. Modelling longitudinal data of both parents simultaneously:
proc mixed data=marital method=ml;
class year parent;
model sat = parent year parent*year / solution noint;
repeated parent*year / type=un subject=famnr r;
run;
proc mixed data=marital method=ml;
class year parent;
model sat = parent year parent*year / solution noint;
repeated parent year / type=un@un subject=famnr r;
run;
proc mixed data=marital method=ml;
class year parent;
model sat = parent year parent*year / solution noint;
repeated parent year / type=un@ar(1) subject=famnr r;
run;
proc mixed data=marital method=ml;
class year parent;
model sat = parent year parent*year / solution noint;
repeated parent year / type=un@cs subject=famnr r;
run;
Part 2
1. Data Management
libname m ’c:\data’;
data maritcc;
set m.maritcc;
YEARCLS = year;
PARENTCLS = parent;
YEARSMAR90 = 1990 - (1900+marr);
AGEBASE = 1990 - (1900+birth);
run;
2. Separate Analysis for Males & Females
DATASET 6. MARITAL SATISFACTION DATA 191
proc sort data=maritcc; by parent; run;
proc genmod data=maritcc descending;
title ’Full Model by Parent: CC - GEE: Type=UN’;
class yearcls idnr;
model bsat = yearsmar90 yearsmar90*year yearsmar90*agebase yearsmar90*educ
yearsmar90*agebase*year yearsmar90*educ*year yearsmar90*educ*agebase /
dist=binomial;
repeated subject=idnr / within=yearcls type=un modelse;
by parent;
run;
* males;
data males;
set maritcc;
where parent=0;
run;
proc genmod data=males descending;
title ’Reduced Model for Males: CC - GEE: Type=UN’;
class yearcls idnr;
model bsat = / dist=binomial;
repeated subject=idnr / within=yearcls type=un modelse;
run;
* females;
data females;
set maritcc;
where parent=1;
run;
proc genmod data=females descending;
title ’Reduced Model for Females: CC - GEE: Type=UN’;
class yearcls idnr;
model bsat = yearsmar90 yearsmar90*year yearsmar90*agebase yearsmar90*educ
yearsmar90*agebase*year yearsmar90*educ*agebase / noint dist=binomial ;
repeated subject=idnr / within=yearcls type=un modelse;
run;
3. Joint Analysis
* full model;
proc genmod data=maritcc descending;
title ’CC - GEE: Full Model: Type=UN’;
class famnr yearcls parentcls;
model bsat = parent*yearsmar90 parent*yearsmar90*year
parent*yearsmar90*agebase parent*yearsmar90*educ
parent*yearsmar90*agebase*year parent*yearsmar90*educ*year
parent*yearsmar90*educ*agebase / dist=binomial;
repeated subject=famnr / within=yearcls(parentcls) type=un modelse corrw;
run;
* reduced model;
proc genmod data=maritcc descending;
DATASET 6. MARITAL SATISFACTION DATA 192
title ’CC - GEE: Reduced Model: Type=UN’;
class famnr yearcls parentcls;
model bsat = parent*yearsmar90 parent*yearsmar90*year
parent*yearsmar90*agebase parent*yearsmar90*educ
parent*yearsmar90*agebase*year / dist=binomial ;
repeated subject=famnr / within=yearcls(parentcls) type=un modelse corrw;
run;
Part 3
1. Data management:
libname MarSat ’C:\QMSS\GLMMs\Data’;
data dat;
set MarSat.marsat (drop = SAT PCOM BPCOM DCOM BDCOM birth educ status income);
yearsmarr = year - (1900 + marr);
drop marr;
run;
proc sort data = dat;
by idnr year famnr;
run;
2. Procedure GLIMMIX - nested random effects:
proc glimmix data = dat method = RSPL NOCLPRINT NOITPRINT;
title ’Nested RE - PQL’;
class famnr parent year;
model bsat(event = ’1’) = year parent parent*year child yearsmarr/ dist = binary solution;
random intercept / subject = famnr;
random intercept / subject = parent(famnr);
run;
proc glimmix data = dat method = RMPL NOCLPRINT NOITPRINT;
title ’Nested RE - MQL’;
class famnr parent year;
model bsat(event = ’1’) = year parent parent*year child yearsmarr/ dist = binary solution;
random intercept / subject = famnr;
random intercept / subject = parent(famnr);
run;
3. Procedure NLMIXED - nested random effects:
proc nlmixed data = dat points = 10;
title ’Nested RE - Adaptive GH (q = 10)’;
parms b0 = 2.8528 b1 = -0.5461 b2 = 0.3003 b3 = 0.1212 b4 = -0.02857
b5 = -0.2657 b6 = 0.06638 b7 = -0.03084
V1 = 2.3957;
eta = b0 + b1 * (year = 1990) + b2 * (year = 1995) +
b3 * (parent = 0) + b4 * (parent = 0) * (year = 1990) +
b5 * (parent = 0) * (year = 1995) + b6 * child +
b7 * yearsmarr +
DATASET 6. MARITAL SATISFACTION DATA 193
g1 * (parent = 0) + g2 * (parent = 1);
expeta = exp(eta);
p = expeta / (1 + expeta);
model bsat ~ binary(p);
random g1 g2 ~ normal([0, 0], [V1 + V2,
V2, V1 + V2]) subject = famnr;
run;
4. Test for the parent random effect:
proc nlmixed data = dat points = 10;
title ’Adaptive GH (q = 10) - No parent RE’;
parms b0 = 2.8528 b1 = -0.5461 b2 = 0.3003 b3 = 0.1212 b4 = -0.02857
b5 = -0.2657 b6 = 0.06638 b7 = -0.03084
V1 = 2.3957;
eta = b0 + b1 * (year = 1990) + b2 * (year = 1995) +
b3 * (parent = 0) + b4 * (parent = 0) * (year = 1990) +
b5 * (parent = 0) * (year = 1995) + b6 * child +
b7 * yearsmarr + g1;
expeta = exp(eta);
p = expeta / (1 + expeta);
model bsat ~ binary(p);
random g1 ~ normal(0, V1**2) subject = famnr;
run;
data LRT;
logL0 = -1203.2/2;
logL1 = -1199.6/2;
LRT = -2 * (logL0 - logL1);
df = 1;
pval = 1 - probchi(LRT, df);
run;
proc print data = LRT;
run;
5. Procedure GLIMMIX for PQL and MQL - random intercepts:
proc glimmix data = dat method = RSPL NOCLPRINT NOITPRINT IC=PQ or;
title ’PQL (REML)’;
class famnr parent year;
nloptions maxit = 50 technique = newrap;
model bsat(event = ’1’) = year parent parent*year child
yearsmarr/ dist = binary solution;
random intercept / subject = famnr;
run;
proc glimmix data = dat method = MSPL NOCLPRINT NOITPRINT IC=PQ or;
title ’PQL (ML)’;
class famnr parent year;
nloptions maxit = 50 technique = newrap;
model bsat(event = ’1’) = year parent parent*year child
yearsmarr/ dist = binary solution;
random intercept / subject = famnr;
DATASET 6. MARITAL SATISFACTION DATA 194
run;
proc glimmix data = dat method = RMPL NOCLPRINT NOITPRINT;
title ’MQL (REML)’;
class famnr parent year;
nloptions maxit = 50 technique = newrap;
model bsat(event = ’1’) = year parent parent*year child
yearsmarr/ dist = binary solution;
random intercept / subject = famnr;
run;
proc glimmix data = dat method = MMPL NOCLPRINT NOITPRINT;
title ’MQL (ML)’;
class famnr parent year;
nloptions maxit = 50 technique = newrap;
model bsat(event = ’1’) = year parent parent*year child
yearsmarr/ dist = binary solution;
random intercept / subject = famnr;
run;
6. Procedure NLMIXED for Gaussian quadrature - random intercepts:
proc nlmixed data = dat noad points = 20;
title ’GH (q = 20)’;
parms b0 = 2.8528 b1 = -0.5465 b2 = 0.3001 b3 = 0.1213 b4 = -0.02867
b5 = -0.2656 b6 = 0.06617 b7 = -0.03079
V1 = 2.3662;
eta = b0 + b1 * (year = 1990) + b2 * (year = 1995) +
b3 * (parent = 0) + b4 * (parent = 0) * (year = 1990) +
b5 * (parent = 0) * (year = 1995) + b6 * child +
b7 * yearsmarr + g1;
expeta = exp(eta);
p = expeta / (1 + expeta);
model bsat ~ binary(p);
random g1 ~ normal(0, V1**2) subject = famnr;
run;
7. Procedure NLMIXED for adaptive Gaussian quadrature - random intercepts:
proc nlmixed data = dat points = 20;
title ’Adaptive GH (q = 20)’;
parms b0 = 2.8528 b1 = -0.5465 b2 = 0.3001 b3 = 0.1213 b4 = -0.02867
b5 = -0.2656 b6 = 0.06617 b7 = -0.03079
V1 = 2.3662;
eta = b0 + b1 * (year = 1990) + b2 * (year = 1995) +
b3 * (parent = 0) + b4 * (parent = 0) * (year = 1990) +
b5 * (parent = 0) * (year = 1995) + b6 * child +
b7 * yearsmarr + g1;
expeta = exp(eta);
p = expeta / (1 + expeta);
model bsat ~ binary(p);
random g1 ~ normal(0, V1**2) subject = famnr;
estimate ’V1^2’ V1*V1;
run;
DATASET 6. MARITAL SATISFACTION DATA 195
8. Procedure NLMIXED for Laplace approximation:
proc nlmixed data = dat points = 1;
title ’Laplace approximation’;
parms b0 = 2.8528 b1 = -0.5465 b2 = 0.3001 b3 = 0.1213 b4 = -0.02867
b5 = -0.2656 b6 = 0.06617 b7 = -0.03079
V1 = 2.3662;
eta = b0 + b1 * (year = 1990) + b2 * (year = 1995) +
b3 * (parent = 0) + b4 * (parent = 0) * (year = 1990) +
b5 * (parent = 0) * (year = 1995) + b6 * child +
b7 * yearsmarr + g1;
expeta = exp(eta);
p = expeta / (1 + expeta);
model bsat ~ binary(p);
random g1 ~ normal(0, V1**2) subject = famnr;
estimate ’V1^2’ V1*V1;
run;
9. Marginal evolutions:
proc univariate data=dat;
var child yearsmarr;
run;
data Simulate;
do parent=0 to 1 by 1;
do subject=1 to 1000 by 1;
b1=rannor(-1);
b1=2.1366*b1;
do t=1 to 3 by 1;
output;
end;
end;
end;
run;
proc sort data=Simulate;
by t parent;
run;
data Simulate;
set Simulate;
child = 2;
marr = 22;
year90 = 0;
year95 = 0;
parent0 = 0;
if t=1 then year90=1;
if t=2 then year95=1;
if parent=0 then parent0=1;
if parent=0 then
y=1/(1+exp(-(4.3383+b1-0.7549*year90+0.4583*year95+0.1511*parent0
-0.02017*parent0*year90-0.3720*parent0*year95+
0.1531*child-0.04538*marr)));
else
y=1/(1+exp(-(4.3383+b1-0.7549*year90+0.4583*year95+
DATASET 6. MARITAL SATISFACTION DATA 196
0.1531*child-0.04538*marr)));
run;
proc means data=Simulate;
var y;
by t parent;
output out=out;
run;
proc gplot data=out;
plot y*t=parent / haxis=axis1 vaxis=axis2 legend=legend1;
axis1 label=(h=2 ’Time Points’) value=(h=1.5) minor=none;
axis2 label=(h=2 A=90 ’P(Y=1)’) value=(h=1.5) order=(0.84 to 0.95 by 0.02) minor=none;
legend1 label=(h=1.5 ’Parent: ’) value=(h=1.5 ’Husband’ ’Wife’);
title h=2.5 ’Marginal average evolutions (GLMM)’;
symbol1 c=black i=join w=5 l=1 mode=include;
symbol2 c=black i=join w=5 l=2 mode=include;
where _stat_=’MEAN’;
run;
quit;
run;
10. Evolutions for the median individual:
proc univariate data=dat;
var child yearsmarr;
run;
data MedianPlot;
do parent=0 to 1 by 1;
b1=0;
b1=2.1366*b1;
do t=1 to 3 by 1;
output;
end;
end;
run;
proc sort data=MedianPlot;
by t parent;
run;
data MedianPlot;
set MedianPlot;
child = 2;
marr = 22;
year90 = 0;
year95 = 0;
parent0 = 0;
if t=1 then year90=1;
if t=2 then year95=1;
if parent=0 then parent0=1;
if parent=0 then
y=1/(1+exp(-(4.3383+b1-0.7549*year90+0.4583*year95+0.1511*parent0
-0.02017*parent0*year90-0.3720*parent0*year95+
0.1531*child-0.04538*marr)));
else
DATASET 6. MARITAL SATISFACTION DATA 197
y=1/(1+exp(-(4.3383+b1-0.7549*year90+0.4583*year95+
0.1531*child-0.04538*marr)));
run;
proc gplot data=MedianPlot;
plot y*t=parent / haxis=axis1 vaxis=axis2 legend=legend1;
axis1 label=(h=2 ’Time Points’) value=(h=1.5) minor=none;
axis2 label=(h=2 A=90 ’P(Y=1)’) value=(h=1.5) order=(0.92 to 1.0 by 0.02) minor=none;
legend1 label=(h=1.5 ’Parent: ’) value=(h=1.5 ’Husband’ ’Wife’);
title h=2.5 ’Evolutions for the median parent’;
symbol1 c=black i=join w=5 l=1 mode=include;
symbol2 c=black i=join w=5 l=2 mode=include;
run;
quit;
run;
11. Test for the parent effect:
proc nlmixed data = dat points = 20;
title ’Adaptive GH (q = 20) - No parent effect’;
parms b0 = 2.8528 b1 = -0.5465 b2 = 0.3001 b3 = 0.1213 b4 = -0.02867
V1 = 2.3662;
eta = b0 + b1 * (year = 1990) + b2 * (year = 1995) + b3 * child +
b4 * yearsmarr + g1;
expeta = exp(eta);
p = expeta / (1 + expeta);
model bsat ~ binary(p);
random g1 ~ normal(0, V1**2) subject = famnr;
run;
data LRT;
logL0 = -1203.8/2;
logL1 = -1203.0/2;
LRT = -2 * (logL0 - logL1);
df = 3;
pval = 1 - probchi(LRT, df);
run;
proc print data = LRT;
run;
Part 4
1. Data management:
/* IC */
PROC IMPORT OUT= WORK.MSDIC
DATAFILE= "C:\QMSS Workshop\Data\MSD\data3_IC.xls"
DBMS=EXCEL REPLACE;
SHEET="Sheet1$";
GETNAMES=YES;
MIXED=NO;
SCANTEXT=YES;
USEDATE=YES;
DATASET 6. MARITAL SATISFACTION DATA 198
SCANTIME=YES;
RUN;
data msdic;
set msdic;
yearcls=year;
parentcls=parent;
drop pcom bpcom dcom bdcom;
run;
proc print data=msdic;
run;
/* CC */
PROC IMPORT OUT= WORK.MSDCC
DATAFILE= "C:\QMSS Workshop\Data\MSD\data3_CC.xls"
DBMS=EXCEL REPLACE;
SHEET="Sheet1$";
GETNAMES=YES;
MIXED=NO;
SCANTEXT=YES;
USEDATE=YES;
SCANTIME=YES;
RUN;
data msdcc;
set msdcc;
drop pcom bpcom dcom bdcom;
run;
proc print data=msdcc;
run;
2. Exploring Missing Data Patterns
data msd1;
set msdic;
if year=1990 then sat1=sat;
if year>1990 then delete;
keep famnr parent sat1;
run;
data msd2;
set msdic;
if year=1995 then sat2=sat;
if year>1995|year<1995 then delete;
keep famnr parent sat2;
run;
data msd3;
set msdic;
if year=2000 then sat3=sat;
if year<2000 then delete;
keep famnr parent sat3;
run;
data misexp;
merge msd1 msd2 msd3;
DATASET 6. MARITAL SATISFACTION DATA 199
by famnr parent;
run;
proc mi data=misexp;
var sat1 sat2 sat3;
run;
3. Continuous Response: Procedure MIXED: CC
proc mixed data=msdcc method=ml;
title ’CONT MIXED, CC’;
class famnr idnr year status parent;
model sat = year parent year*parent / s noint;
repeated parent year / type=un@CS subject=famnr r rcorr;
run;
4. Continuous Response: Procedure MIXED: Direct Likelihood
proc mixed data=msdic method=ml;
title ’CONT MIXED Direct Likelihood’;
class famnr idnr year status parent;
model sat = year parent year*parent / s noint;
repeated parent year / type=un@cs subject=famnr r rcorr;
run;
5. Continuous Response: Procedure MIXED: Multiple Imputation
proc MI data = msdic out = msdiccomp NOPRINT;
mcmc initial=em (bootstrap = 0.85)
prior = JEFFREYS
chain = multiple;
run;
/* Transforming the data for Mixed model (Creating dummies) */
data msdiccomp;
title ’CONT MIXED MULTIPLE IMPUTATION’;
set msdiccomp;
year1990 = 0;
year1995 = 0;
year2000 = 0;
if year = 1990 then year1990 = 1;
if year = 1995 then year1995 = 1;
if year = 2000 then year2000 = 1;
father = 0;
mother = 0;
if Parent = 0 then father = 1;
if Parent = 1 then mother = 1;
father1990 = 0;
father1995 = 0;
father2000 = 0;
mother1990 = 0;
mother1995 = 0;
mother2000 = 0;
if (father = 1) and (year = 1990) then father1990 = 1;
if (father = 1) and (year = 1995) then father1995 = 1;
if (father = 1) and (year = 2000) then father2000 = 1;
if (mother = 1) and (year = 1990) then mother1990 = 1;
if (mother = 1) and (year = 1995) then mother1995 = 1;
if (mother = 1) and (year = 2000) then mother2000 = 1;
DATASET 6. MARITAL SATISFACTION DATA 200
run;
/* Analysing 5 Completed Datasets */
proc mixed data=msdiccomp method = ml asycov covtest;
title2 ’MIXED MODEL ANALYSIS PER IMPUTATION’;
class famnr year parent ;
model sat = year1990 year1995 year2000 father father1990 father1995 / s noint covb;
repeated year parent / subject=famnr type=un@cs rcorr;
ods output solutionf = solution covb = covb covparms = covparms asycov = asycov;
by _imputation_;
data solution0;
set solution;
data covb0;
set covb;
data covparms0;
set covparms;
if CovParm=’YEAR UN(1,1)’ then effect = ’YEARUN11’;
if CovParm=’ UN(2,1)’ then effect = ’YEARUN21’;
if CovParm=’ UN(2,2)’ then effect = ’YEARUN22’;
if CovParm=’ UN(3,1)’ then effect = ’YEARUN31’;
if CovParm=’ UN(3,2)’ then effect = ’YEARUN32’;
if CovParm=’ UN(3,3)’ then effect = ’YEARUN33’;
if CovParm=’PARENT Corr’ then effect = ’PARENTCORR’ ;
drop covparm;
data asycov0;
set asycov;
Col1=CovP1;
Col2=CovP2;
Col3=CovP3;
Col4=CovP4;
Col5=CovP5;
Col6=CovP6;
Col7=CovP7;
if CovParm=’YEAR UN(1,1)’ then effect = ’YEARUN11’;
if CovParm=’ UN(2,1)’ then effect = ’YEARUN21’;
if CovParm=’ UN(2,2)’ then effect = ’YEARUN22’;
if CovParm=’ UN(3,1)’ then effect = ’YEARUN31’;
if CovParm=’ UN(3,2)’ then effect = ’YEARUN32’;
if CovParm=’ UN(3,3)’ then effect = ’YEARUN33’;
if CovParm=’PARENT Corr’ then effect = ’PARENTCORR’ ;
drop CovP1 CovP2 CovP3 CovP4 CovP5 CovP6 CovP7 covparm;
run;
/* Combining 5 Separate Analyses (mean structure) */
proc mianalyze parms=solution0 covb(effectvar=rowcol)=covb0;
title2 ’COMBINING 5 MIXED MODEL ANALYSES (MEAN STRUCTURE)’;
modeleffects year1990 year1995 year2000 father father1990 father1995;
run;
/* Combining 5 Separate Analyses (covariance structure) */
proc mianalyze parms=covparms0 covb(effectvar=rowcol)=asycov0;
title2 ’COMBINING 5 MIXED MODEL ANALYSES (COVARIANCE STRUCTURE)’;
modeleffects YEARUN11 YEARUN21 YEARUN22 YEARUN31 YEARUN32 YEARUN33 PARENTCO;
run;
6. Binary Response: Procedure GEE: CC
proc genmod data=msdcc descending;
title ’BIN GEE CC’;
DATASET 6. MARITAL SATISFACTION DATA 201
class famnr year parent;
model bsat = parent year birth parent*year parent*birth birth*year parent*birth*year
/dist=binomial type3;
repeated subject=famnr / within=year(parent) type=un modelse corrw;
run;
7. Binary Response: Procedure GEE: WGEE
/* Use the WGEE MACRO FOR CREATING VARIABLES "DROPOUT" AND "PREV" */
%dropout(data=msdic,id=famnr,time=year,response=bsat,out=msdicwgee);
proc print data=msdicwgee;
title ’BIN WGEE’;
run;
proc genmod data=msdicwgee descending;
title ’BIN WGEE’;
title2 ’Dropout Model’;
class famnr year status prev;
model dropout = prev parent year birth/ pred dist=b;
ods output obstats=pred;
ods listing exclude obstats;
run;
data pred;
set pred;
keep observation pred;
run;
data msdicwgee1;
merge pred msdicwgee;
run;
/* Use the WGEE MACRO TO CREATE THE WEIGHTING VARIABLE */
%dropwgt(data=msdicwgee1,id=famnr,time=year,pred=pred,dropout=dropout,out=msdicwgee2);
proc print data=msdicwgee2;
var famnr year bsat dropout prev pred wi;
run;
/* WGEE model */
proc genmod data=msdicwgee2 descending;
title ’BIN WGEE’;
scwgt wi;
class famnr year parent ;
model bsat = parent year birth parent*year parent*birth birth*year parent*birth*year
/dist=binomial type3;
repeated subject=famnr / within=year(parent) type=un modelse corrw;
run;
8. Binary Response: Procedure GEE: Available Cases
proc genmod data=msdic descending;
title ’BIN GEE Available Cases’;
class famnr year parent ;
model bsat = parent year birth parent*year parent*birth year*birth parent*year*birth
/ dist=binomial type3;
repeated subject=famnr / within=year(parent) type=un modelse corrw;
run;
DATASET 6. MARITAL SATISFACTION DATA 202
9. Binary Response: Procedure GEE: Multiple Imputation
proc MI data = msdic out = msdiccomp NOPRINT;
mcmc initial=em (bootstrap = 0.85)
prior = JEFFREYS
chain = multiple;
run;
/* Transforming the data for MI GEE (Creating dummies) */
data msdiccomp;
title1 ’BIN GEE MULTIPLE IMPUTATION’;
set msdiccomp;
if SAT <= 4 then BSAT = 0;
if SAT > 4 then BSAT = 1;
year1990 = 0;
year1995 = 0;
year2000 = 0;
if year = 1990 then year1990 = 1;
if year = 1995 then year1995 = 1;
if year = 2000 then year2000 = 1;
father = 0;
mother = 0;
if Parent = 0 then father = 1;
if Parent = 1 then mother = 1;
father1990 = 0;
father1995 = 0;
father2000 = 0;
mother1990 = 0;
mother1995 = 0;
mother2000 = 0;
if (father = 1) and (year = 1990) then father1990 = 1;
if (father = 1) and (year = 1995) then father1995 = 1;
if (father = 1) and (year = 2000) then father2000 = 1;
if (mother = 1) and (year = 1990) then mother1990 = 1;
if (mother = 1) and (year = 1995) then mother1995 = 1;
if (mother = 1) and (year = 2000) then mother2000 = 1;
fatherbirth = 0;
motherbirth = 0;
if father = 1 then fatherbirth = birth;
if mother = 1 then motherbirth = birth;
birth1990 = 0;
birth1995 = 0;
birth2000 = 0;
if year = 1990 then birth1990 = birth;
if year = 1995 then birth1995 = birth;
if year = 2000 then birth2000 = birth;
father1990birth = 0;
father1995birth = 0;
father2000birth = 0;
mother1990birth = 0;
mother1995birth = 0;
mother2000birth = 0;
if (father = 1) and (year = 1990) then father1990birth = birth;
if (father = 1) and (year = 1995) then father1995birth = birth;
if (father = 1) and (year = 2000) then father2000birth = birth;
if (mother = 1) and (year = 1990) then mother1990birth = birth;
if (mother = 1) and (year = 1995) then mother1995birth = birth;
if (mother = 1) and (year = 2000) then mother2000birth = birth;
run;
DATASET 6. MARITAL SATISFACTION DATA 203
/* Analysing 5 Completed Datasets */
proc genmod data=msdiccomp descending;
title2 ’GEE ANALYSIS PER IMPUTATION’;
class famnr year parent ;
model bsat = father year1990 year1995 BIRTH father1990 father1995 fatherbirth
birth1990 birth1995 father1990birth father1995birth
/ dist=binomial type3 covb;
repeated subject=famnr / within=year(parent) type=un modelse corrw;
ods output parameterestimates = gmparms parminfo = gmpinfo covb = gmcovb;
by _imputation_;
data gmparms;
set gmparms;
if parameter in (’Scale’) then delete;
data gmcovb;
set gmcovb;
data gmpinfo;
set gmpinfo;
run;
/* Combining 5 Separate Analyses */
proc mianalyze parms = gmparms covb = gmcovb parminfo = gmpinfo;
title2 ’COMBINING 5 GEE ANALYSES’;
modeleffects intercept father year1990 year1995 BIRTH father1990 father1995 fatherbirth
birth1990 birth1995 father1990birth father1995birth;
run;
10. Binary Response: Procedure NLMIXED: CC
proc logistic data=msdcc;
title ’Determining the starting values for the CC GLMM’;
class year parent;
model bsat=parent year birth parent*year parent*birth birth*year parent*birth*year;
run;
proc nlmixed data = msdcc points = 10;
title ’CC GLMM’;
parms b0 = -3 b1 = -1.5 b2 = -0.9 b3 = 0.1 b4 = 0.008
b5 = 1.1 b6 = 3.1 b7 = 0.002 b8 = 0.04 b9 = 0.01 b10 = -0.02 b11 = -0.065
V1 = 2.3662;
eta = b0 + b1 * (year = 1990) + b2 * (year = 1995) + b3 * (parent = 0) + b4 * birth +
b5 * (parent = 0) * (year = 1990) + b6 * (parent = 0) * (year = 1995) +
b7 * (parent = 0) * birth + b8 * birth * (year = 1990) +
b9 * birth * (year = 1995) + b10 * birth * (year = 1990) * (parent = 0) +
b11 * birth * (year = 1995) * (parent = 0) + g1;
expeta = exp(eta);
p = expeta / (1 + expeta);
model bsat ~ binary(p);
random g1 ~ normal(0, V1**2) subject = famnr;
run;
11. Binary Response: Procedure NLMIXED: Direct Likelihood
proc nlmixed data = msdic points = 10;
title ’Direct Likelihood GLMM’;
parms b0 = -3 b1 = -1.5 b2 = -0.9 b3 = 0.1 b4 = 0.008
b5 = 1.1 b6 = 3.1 b7 = 0.002 b8 = 0.04 b9 = 0.01 b10 = -0.02 b11 = -0.065
V1 = 2.3662;
eta = b0 + b1 * (year = 1990) + b2 * (year = 1995) + b3 * (parent = 0) + b4 * birth +
b5 * (parent = 0) * (year = 1990) + b6 * (parent = 0) * (year = 1995) +
b7 * (parent = 0) * birth + b8 * birth * (year = 1990) +
b9 * birth * (year = 1995) + b10 * birth * (year = 1990) * (parent = 0) +
DATASET 6. MARITAL SATISFACTION DATA 204
b11 * birth * (year = 1995) * (parent = 0) + g1;
expeta = exp(eta);
p = expeta / (1 + expeta);
model bsat ~ binary(p);
random g1 ~ normal(0, V1**2) subject = famnr;
run;
6.3.2 SAS Output
Part 1
2. Full model with unstructured mean and covariance structure
(a) Fathers:
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) IDNR 0.5494
UN(2,1) IDNR 0.3786
UN(2,2) IDNR 0.8045
UN(3,1) IDNR 0.4058
UN(3,2) IDNR 0.5957
UN(3,3) IDNR 0.9409
Fit Statistics
-2 Log Likelihood 795.8
AIC (smaller is better) 823.8
AICC (smaller is better) 825.0
BIC (smaller is better) 863.0
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
5 142.39 <.0001
Solution for Fixed Effects
Standard
Effect YEAR STATUS Estimate Error DF t Value Pr > |t|
YEAR 1990 4.2185 1.6399 118 2.57 0.0113
YEAR 1995 4.9972 1.6461 118 3.04 0.0030
YEAR 2000 4.7205 1.6464 118 2.87 0.0049
CHILD 0.04839 0.04897 118 0.99 0.3251
BIRTH 0.008740 0.01883 118 0.46 0.6435
EDUC -0.03250 0.03742 118 -0.87 0.3869
DATASET 6. MARITAL SATISFACTION DATA 205
MARR 0.008137 0.02700 118 0.30 0.7637
INCOME 0.02918 0.05456 118 0.53 0.5937
STATUS 1 -0.1992 0.1857 118 -1.07 0.2856
STATUS 2 0 . . . .
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 2 118 53.77 <.0001
CHILD 1 118 0.98 0.3251
BIRTH 1 118 0.22 0.6435
EDUC 1 118 0.75 0.3869
MARR 1 118 0.09 0.7637
INCOME 1 118 0.29 0.5937
STATUS 1 118 1.15 0.2856
(b) Mothers:
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) IDNR 0.6559
UN(2,1) IDNR 0.3990
UN(2,2) IDNR 0.9592
UN(3,1) IDNR 0.3583
UN(3,2) IDNR 0.5691
UN(3,3) IDNR 0.9002
Fit Statistics
-2 Log Likelihood 869.6
AIC (smaller is better) 897.6
AICC (smaller is better) 898.8
BIC (smaller is better) 936.9
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
5 103.99 <.0001
Solution for Fixed Effects
Standard
Effect YEAR STATUS Estimate Error DF t Value Pr > |t|
YEAR 1990 7.1128 1.7919 118 3.97 0.0001
YEAR 1995 7.7785 1.7988 118 4.32 <.0001
DATASET 6. MARITAL SATISFACTION DATA 206
YEAR 2000 7.5638 1.7987 118 4.21 <.0001
CHILD -0.00229 0.05124 118 -0.04 0.9645
BIRTH 0.01256 0.02824 118 0.44 0.6574
EDUC -0.02235 0.04469 118 -0.50 0.6180
MARR -0.02964 0.03577 118 -0.83 0.4090
INCOME -0.01205 0.05385 118 -0.22 0.8234
STATUS 1 -0.2059 0.1894 118 -1.09 0.2792
STATUS 2 0 . . . .
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 2 118 30.03 <.0001
CHILD 1 118 0.00 0.9645
BIRTH 1 118 0.20 0.6574
EDUC 1 118 0.25 0.6180
MARR 1 118 0.69 0.4090
INCOME 1 118 0.05 0.8234
STATUS 1 118 1.18 0.2792
3. Final model after reducing mean structure
(a) Fathers:
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) IDNR 0.5596
UN(2,1) IDNR 0.3881
UN(2,2) IDNR 0.8222
UN(3,1) IDNR 0.4049
UN(3,2) IDNR 0.5991
UN(3,3) IDNR 0.9300
Fit Statistics
-2 Log Likelihood 799.2
AIC (smaller is better) 817.2
AICC (smaller is better) 817.7
BIC (smaller is better) 842.4
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
5 144.10 <.0001
Solution for Fixed Effects
DATASET 6. MARITAL SATISFACTION DATA 207
Standard
Effect YEAR Estimate Error DF t Value Pr > |t|
YEAR 1990 5.2266 0.06773 122 77.17 <.0001
YEAR 1995 6.0236 0.08209 122 73.38 <.0001
YEAR 2000 5.7469 0.08731 122 65.82 <.0001
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 3 122 2438.85 <.0001
(b) Mothers:
Fit Statistics
-2 Log Likelihood 872.0
AIC (smaller is better) 890.0
AICC (smaller is better) 890.5
BIC (smaller is better) 915.3
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
5 104.13 <.0001
Solution for Fixed Effects
Standard
Effect YEAR Estimate Error DF t Value Pr > |t|
YEAR 1990 5.2588 0.07476 122 70.34 <.0001
YEAR 1995 5.9184 0.08878 122 66.66 <.0001
YEAR 2000 5.7037 0.08520 122 66.95 <.0001
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 3 122 2268.91 <.0001
4. Reducing the covariance structure
(a) Fathers:
• Unstructured - UN
Covariance Parameter Estimates
DATASET 6. MARITAL SATISFACTION DATA 208
Cov Parm Subject Estimate
UN(1,1) IDNR 0.5596
UN(2,1) IDNR 0.3881
UN(2,2) IDNR 0.8222
UN(3,1) IDNR 0.4049
UN(3,2) IDNR 0.5991
UN(3,3) IDNR 0.9300
Fit Statistics
-2 Log Likelihood 799.2
AIC (smaller is better) 817.2
AICC (smaller is better) 817.7
BIC (smaller is better) 842.4
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
5 144.10 <.0001
• Banded - UN(2)
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) IDNR 0.5596
UN(2,1) IDNR 0.1859
UN(2,2) IDNR 0.6878
UN(3,1) IDNR 0
UN(3,2) IDNR 0.4646
UN(3,3) IDNR 0.9300
Fit Statistics
-2 Log Likelihood 845.3
AIC (smaller is better) 861.3
AICC (smaller is better) 861.7
BIC (smaller is better) 883.8
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
4 97.95 <.0001
• Heterogeneous Autoregressive - ARH(1)
Covariance Parameter Estimates
Cov Parm Subject Estimate
DATASET 6. MARITAL SATISFACTION DATA 209
Var(1) IDNR 0.5856
Var(2) IDNR 0.8222
Var(3) IDNR 0.8906
ARH(1) IDNR 0.6298
Fit Statistics
-2 Log Likelihood 812.1
AIC (smaller is better) 826.1
AICC (smaller is better) 826.4
BIC (smaller is better) 845.7
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
3 131.22 <.0001
• Heterogeneous Compound Symmetry - CSH
Covariance Parameter Estimates
Cov Parm Subject Estimate
Var(1) IDNR 0.5793
Var(2) IDNR 0.8066
Var(3) IDNR 0.9165
CSH IDNR 0.6067
Fit Statistics
-2 Log Likelihood 804.4
AIC (smaller is better) 818.4
AICC (smaller is better) 818.7
BIC (smaller is better) 838.0
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
3 138.87 <.0001
• Heterogeneous Toeplitz - TOEPH
Covariance Parameter Estimates
Cov Parm Subject Estimate
Var(1) IDNR 0.5770
Var(2) IDNR 0.8222
Var(3) IDNR 0.9028
TOEPH(1) IDNR 0.6295
TOEPH(2) IDNR 0.5610
DATASET 6. MARITAL SATISFACTION DATA 210
Fit Statistics
-2 Log Likelihood 802.7
AIC (smaller is better) 818.7
AICC (smaller is better) 819.1
BIC (smaller is better) 841.1
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
4 140.62 <.0001
• Compound Symmetry - CS
Covariance Parameter Estimates
Cov Parm Subject Estimate
CS IDNR 0.4640
Residual 0.3066
Fit Statistics
-2 Log Likelihood 814.8
AIC (smaller is better) 824.8
AICC (smaller is better) 825.0
BIC (smaller is better) 838.8
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
1 128.48 <.0001
(b) Mothers:
• Unstructured - UN
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) IDNR 0.6819
UN(2,1) IDNR 0.4139
UN(2,2) IDNR 0.9616
UN(3,1) IDNR 0.3637
UN(3,2) IDNR 0.5629
UN(3,3) IDNR 0.8855
Fit Statistics
-2 Log Likelihood 872.0
DATASET 6. MARITAL SATISFACTION DATA 211
AIC (smaller is better) 890.0
AICC (smaller is better) 890.5
BIC (smaller is better) 915.3
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
5 104.13 <.0001
• Banded - UN(2)
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) IDNR 0.6819
UN(2,1) IDNR 0.2340
UN(2,2) IDNR 0.8381
UN(3,1) IDNR 0
UN(3,2) IDNR 0.4381
UN(3,3) IDNR 0.8855
Fit Statistics
-2 Log Likelihood 902.2
AIC (smaller is better) 918.2
AICC (smaller is better) 918.6
BIC (smaller is better) 940.6
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
4 73.98 <.0001
• Heterogeneous Autoregressive - ARH(1)
Covariance Parameter Estimates
Cov Parm Subject Estimate
Var(1) IDNR 0.7051
Var(2) IDNR 0.9616
Var(3) IDNR 0.8573
ARH(1) IDNR 0.5614
Fit Statistics
-2 Log Likelihood 880.1
AIC (smaller is better) 894.1
AICC (smaller is better) 894.4
BIC (smaller is better) 913.8
DATASET 6. MARITAL SATISFACTION DATA 212
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
3 96.03 <.0001
• Heterogeneous Compound Symmetry - CSH
Covariance Parameter Estimates
Cov Parm Subject Estimate
Var(1) IDNR 0.7037
Var(2) IDNR 0.9395
Var(3) IDNR 0.8791
CSH IDNR 0.5303
Fit Statistics
-2 Log Likelihood 876.3
AIC (smaller is better) 890.3
AICC (smaller is better) 890.6
BIC (smaller is better) 909.9
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
3 99.89 <.0001
• Heterogeneous Toeplitz - TOEPH
Covariance Parameter Estimates
Cov Parm Subject Estimate
Var(1) IDNR 0.6991
Var(2) IDNR 0.9616
Var(3) IDNR 0.8643
TOEPH(1) IDNR 0.5612
TOEPH(2) IDNR 0.4678
Fit Statistics
-2 Log Likelihood 873.9
AIC (smaller is better) 889.9
AICC (smaller is better) 890.3
BIC (smaller is better) 912.3
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
DATASET 6. MARITAL SATISFACTION DATA 213
4 102.26 <.0001
• Compound Symmetry - CS
Covariance Parameter Estimates
Cov Parm Subject Estimate
CS IDNR 0.4468
Residual 0.3962
Fit Statistics
-2 Log Likelihood 880.1
AIC (smaller is better) 890.1
AICC (smaller is better) 890.3
BIC (smaller is better) 904.1
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
1 96.07 <.0001
• Simple Structure
Covariance Parameter
Estimates
Cov Parm Subject Estimate
YEAR IDNR 0.8430
Fit Statistics
-2 Log Likelihood 976.2
AIC (smaller is better) 984.2
AICC (smaller is better) 984.3
BIC (smaller is better) 995.4
5. Modelling longitudinal data of both parents simultaneously:
• Unstructured 6 × 6 covariance matrix
Estimated R Matrix for Subject 1
Row Col1 Col2 Col3 Col4 Col5 Col6
1 0.5596 0.2454 0.3881 0.2620 0.4049 0.2285
2 0.2454 0.6819 0.3069 0.4139 0.2871 0.3637
3 0.3881 0.3069 0.8222 0.4211 0.5991 0.3913
4 0.2620 0.4139 0.4211 0.9616 0.4414 0.5629
5 0.4049 0.2871 0.5991 0.4414 0.9300 0.5107
6 0.2285 0.3637 0.3913 0.5629 0.5107 0.8855
DATASET 6. MARITAL SATISFACTION DATA 214
Covariance Parameter Estimates
Cov Parm Subject Estimate
UN(1,1) FAMNR 0.5596
UN(2,1) FAMNR 0.2454
UN(2,2) FAMNR 0.6819
UN(3,1) FAMNR 0.3881
UN(3,2) FAMNR 0.3069
UN(3,3) FAMNR 0.8222
UN(4,1) FAMNR 0.2620
UN(4,2) FAMNR 0.4139
UN(4,3) FAMNR 0.4211
UN(4,4) FAMNR 0.9616
UN(5,1) FAMNR 0.4049
UN(5,2) FAMNR 0.2871
UN(5,3) FAMNR 0.5991
UN(5,4) FAMNR 0.4414
UN(5,5) FAMNR 0.9300
UN(6,1) FAMNR 0.2285
UN(6,2) FAMNR 0.3637
UN(6,3) FAMNR 0.3913
UN(6,4) FAMNR 0.5629
UN(6,5) FAMNR 0.5107
UN(6,6) FAMNR 0.8855
Fit Statistics
-2 Log Likelihood 1603.4
AIC (smaller is better) 1655.4
AICC (smaller is better) 1657.4
BIC (smaller is better) 1728.3
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
20 316.76 <.0001
Solution for Fixed Effects
Standard
Effect YEAR PARENT Estimate Error DF t Value Pr > |t|
PARENT 0 5.7469 0.08731 122 65.82 <.0001
PARENT 1 5.7037 0.08520 122 66.95 <.0001
YEAR 1990 -0.4450 0.08298 122 -5.36 <.0001
YEAR 1995 0.2147 0.07689 122 2.79 0.0061
YEAR 2000 0 . . . .
YEAR*PARENT 1990 0 -0.07533 0.09228 122 -0.82 0.4159
DATASET 6. MARITAL SATISFACTION DATA 215
YEAR*PARENT 1990 1 0 . . . .
YEAR*PARENT 1995 0 0.06206 0.09396 122 0.66 0.5102
YEAR*PARENT 1995 1 0 . . . .
YEAR*PARENT 2000 0 0 . . . .
YEAR*PARENT 2000 1 0 . . . .
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
PARENT 1 122 0.40 0.5285
YEAR 2 122 80.08 <.0001
YEAR*PARENT 2 122 0.95 0.3913
• Unstructured @ Unstructured
Estimated R Matrix for Subject 1
Row Col1 Col2 Col3 Col4 Col5 Col6
1 0.5490 0.2008 0.3143 0.1149 0.3094 0.1131
2 0.2008 0.6620 0.1149 0.3790 0.1131 0.3730
3 0.3143 0.1149 0.7672 0.2805 0.4574 0.1673
4 0.1149 0.3790 0.2805 0.9251 0.1673 0.5516
5 0.3094 0.1131 0.4574 0.1673 0.7618 0.2786
6 0.1131 0.3730 0.1673 0.5516 0.2786 0.9186
Covariance Parameter Estimates
Cov Parm Subject Estimate
PARENT UN(1,1) FAMNR 0.5490
UN(2,1) FAMNR 0.2008
UN(2,2) FAMNR 0.6620
YEAR UN(1,1) FAMNR 1.0000
UN(2,1) FAMNR 0.5725
UN(2,2) FAMNR 1.3973
UN(3,1) FAMNR 0.5634
UN(3,2) FAMNR 0.8331
UN(3,3) FAMNR 1.3875
Fit Statistics
-2 Log Likelihood 1633.8
AIC (smaller is better) 1659.8
AICC (smaller is better) 1660.3
BIC (smaller is better) 1696.2
Null Model Likelihood Ratio Test
DATASET 6. MARITAL SATISFACTION DATA 216
DF Chi-Square Pr > ChiSq
7 286.42 <.0001
Solution for Fixed Effects
Standard
Effect YEAR PARENT Estimate Error DF t Value Pr > |t|
PARENT 0 5.7469 0.07902 121 72.73 <.0001
PARENT 1 5.7037 0.08677 121 65.73 <.0001
YEAR 1990 -0.4450 0.08271 242 -5.38 <.0001
YEAR 1995 0.2147 0.07791 242 2.76 0.0063
YEAR 2000 0 . . . .
YEAR*PARENT 1990 0 -0.07533 0.09146 242 -0.82 0.4109
YEAR*PARENT 1990 1 0 . . . .
YEAR*PARENT 1995 0 0.06206 0.08615 242 0.72 0.4720
YEAR*PARENT 1995 1 0 . . . .
YEAR*PARENT 2000 0 0 . . . .
YEAR*PARENT 2000 1 0 . . . .
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
PARENT 1 121 0.26 0.6089
YEAR 2 242 65.13 <.0001
YEAR*PARENT 2 242 1.14 0.3228
• Unstructured @ Autoregressive
Estimated R Matrix for Subject 1
Row Col1 Col2 Col3 Col4 Col5 Col6
1 0.6933 0.2562 0.3671 0.1357 0.1944 0.07183
2 0.2562 0.8171 0.1357 0.4327 0.07183 0.2291
3 0.3671 0.1357 0.6933 0.2562 0.3671 0.1357
4 0.1357 0.4327 0.2562 0.8171 0.1357 0.4327
5 0.1944 0.07183 0.3671 0.1357 0.6933 0.2562
6 0.07183 0.2291 0.1357 0.4327 0.2562 0.8171
Covariance Parameter Estimates
Cov Parm Subject Estimate
PARENT UN(1,1) FAMNR 0.6933
UN(2,1) FAMNR 0.2562
UN(2,2) FAMNR 0.8171
YEAR AR(1) FAMNR 0.5295
DATASET 6. MARITAL SATISFACTION DATA 217
Fit Statistics
-2 Log Likelihood 1663.7
AIC (smaller is better) 1681.7
AICC (smaller is better) 1682.0
BIC (smaller is better) 1707.0
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
3 256.45 <.0001
Solution for Fixed Effects
Standard
Effect YEAR PARENT Estimate Error DF t Value Pr > |t|
PARENT 0 5.7469 0.07539 121 76.23 <.0001
PARENT 1 5.7037 0.08184 121 69.69 <.0001
YEAR 1990 -0.4450 0.09818 242 -4.53 <.0001
YEAR 1995 0.2147 0.07939 242 2.70 0.0073
YEAR 2000 0 . . . .
YEAR*PARENT 1990 0 -0.07533 0.1085 242 -0.69 0.4882
YEAR*PARENT 1990 1 0 . . . .
YEAR*PARENT 1995 0 0.06206 0.08774 242 0.71 0.4800
YEAR*PARENT 1995 1 0 . . . .
YEAR*PARENT 2000 0 0 . . . .
YEAR*PARENT 2000 1 0 . . . .
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
PARENT 1 121 0.29 0.5910
YEAR 2 242 68.74 <.0001
YEAR*PARENT 2 242 1.29 0.2780
• Unstructured @ Compound Symmetry
Estimated R Matrix for Subject 1
Row Col1 Col2 Col3 Col4 Col5 Col6
1 0.7011 0.2696 0.3620 0.1392 0.3620 0.1392
2 0.2696 0.8309 0.1392 0.4290 0.1392 0.4290
3 0.3620 0.1392 0.7011 0.2696 0.3620 0.1392
4 0.1392 0.4290 0.2696 0.8309 0.1392 0.4290
5 0.3620 0.1392 0.3620 0.1392 0.7011 0.2696
6 0.1392 0.4290 0.1392 0.4290 0.2696 0.8309
DATASET 6. MARITAL SATISFACTION DATA 218
Covariance Parameter Estimates
Cov Parm Subject Estimate
PARENT UN(1,1) FAMNR 0.7011
UN(2,1) FAMNR 0.2696
UN(2,2) FAMNR 0.8309
YEAR Corr FAMNR 0.5164
Fit Statistics
-2 Log Likelihood 1649.4
AIC (smaller is better) 1667.4
AICC (smaller is better) 1667.6
BIC (smaller is better) 1692.6
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
3 270.80 <.0001
Solution for Fixed Effects
Standard
Effect YEAR PARENT Estimate Error DF t Value Pr > |t|
PARENT 0 5.7469 0.07581 121 75.81 <.0001
PARENT 1 5.7037 0.08253 121 69.11 <.0001
YEAR 1990 -0.4450 0.08116 242 -5.48 <.0001
YEAR 1995 0.2147 0.08116 242 2.64 0.0087
YEAR 2000 0 . . . .
YEAR*PARENT 1990 0 -0.07533 0.08872 242 -0.85 0.3967
YEAR*PARENT 1990 1 0 . . . .
YEAR*PARENT 1995 0 0.06206 0.08872 242 0.70 0.4849
YEAR*PARENT 1995 1 0 . . . .
YEAR*PARENT 2000 0 0 . . . .
YEAR*PARENT 2000 1 0 . . . .
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
PARENT 1 121 0.27 0.6031
YEAR 2 242 66.89 <.0001
YEAR*PARENT 2 242 1.20 0.3021
DATASET 6. MARITAL SATISFACTION DATA 219
Part 2
1. Separate Analysis for Males & Females
Full Model by Parent: CC - GEE: Type=UN
PARENT=0
Model Information
Data Set WORK.MARITCC
Distribution Binomial
Link Function Logit
Dependent Variable BSAT
Number of Observations Read 366
Number of Observations Used 366
Number of Events 339
Number of Trials 366
Class Level Information
Class Levels Values
YEARCLS 3 1990 1995 2000
IDNR 122 23 25 39 47 77 83 91 93 101 111 119 129 133 135
137 139 145 159 195 247 249 277 285 287 313 331
339 341 345 361 363 373 385 411 415 423 425 433
439 443 447 453 455 469 479 505 509 519 547 551
557 565 577 597 621 625 629 639 643 645 661 663
673 681 695 ...
Response Profile
Ordered Total
Value BSAT Frequency
1 1 339
2 0 27
PROC GENMOD is modeling the probability that BSAT=’1’.
Parameter Information
Parameter Effect
Prm1 Intercept
Prm2 YEARSMAR90
Prm3 YEARSMAR90*YEAR
Prm4 YEARSMAR90*AGEBASE
DATASET 6. MARITAL SATISFACTION DATA 220
Prm5 YEARSMAR90*EDUC
Prm6 YEARSMA*YEAR*AGEBASE
Prm7 YEARSMAR90*YEAR*EDUC
Prm8 YEARSMA*AGEBASE*EDUC
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 358 191.3000 0.5344
Scaled Deviance 358 191.3000 0.5344
Pearson Chi-Square 358 364.3476 1.0177
Scaled Pearson X2 358 364.3476 1.0177
Log Likelihood -95.6500
Algorithm converged.
Analysis Of Initial Parameter Estimates
Standard Wald 95% Chi-
Parameter DF Estimate Error Confidence Limits Square Pr > ChiSq
Intercept 1 3.3960 1.6584 0.1455 6.6465 4.19 0.0406
YEARSMAR90 1 20.3422 58.0975 -93.5269 134.2112 0.12 0.7262
YEARSMAR90*YEAR 1 -0.0103 0.0291 -0.0673 0.0468 0.12 0.7245
YEARSMAR90*AGEBASE 1 -0.3881 1.3206 -2.9765 2.2003 0.09 0.7689
YEARSMAR90*EDUC 1 -1.1199 2.6958 -6.4036 4.1638 0.17 0.6778
YEARSMA*YEAR*AGEBASE 1 0.0002 0.0007 -0.0011 0.0015 0.09 0.7675
YEARSMAR90*YEAR*EDUC 1 0.0006 0.0013 -0.0021 0.0032 0.17 0.6795
YEARSMA*AGEBASE*EDUC 1 0.0001 0.0014 -0.0026 0.0028 0.00 0.9486
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
GEE Model Information
Correlation Structure Unstructured
Within-Subject Effect YEARCLS (3 levels)
Subject Effect IDNR (122 levels)
Number of Clusters 122
Correlation Matrix Dimension 3
Maximum Cluster Size 3
Minimum Cluster Size 3
Algorithm converged.
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
DATASET 6. MARITAL SATISFACTION DATA 221
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 3.1348 2.2989 -1.3709 7.6405 1.36 0.1727
YEARSMAR90 30.4460 28.6533 -25.7135 86.6055 1.06 0.2880
YEARSMAR90*YEAR -0.0153 0.0144 -0.0435 0.0128 -1.07 0.2856
YEARSMAR90*AGEBASE -0.6467 0.6056 -1.8338 0.5403 -1.07 0.2856
YEARSMAR90*EDUC -0.6050 2.1619 -4.8422 3.6322 -0.28 0.7796
YEARSMA*YEAR*AGEBASE 0.0003 0.0003 -0.0003 0.0009 1.07 0.2837
YEARSMAR90*YEAR*EDUC 0.0003 0.0011 -0.0018 0.0024 0.28 0.7766
YEARSMA*AGEBASE*EDUC -0.0003 0.0019 -0.0040 0.0035 -0.14 0.8857
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 3.1348 2.3166 -1.4056 7.6751 1.35 0.1760
YEARSMAR90 30.4460 38.7133 -45.4308 106.3227 0.79 0.4316
YEARSMAR90*YEAR -0.0153 0.0194 -0.0534 0.0227 -0.79 0.4293
YEARSMAR90*AGEBASE -0.6467 0.8869 -2.3851 1.0916 -0.73 0.4659
YEARSMAR90*EDUC -0.6050 1.8193 -4.1708 2.9608 -0.33 0.7395
YEARSMA*YEAR*AGEBASE 0.0003 0.0004 -0.0005 0.0012 0.73 0.4638
YEARSMAR90*YEAR*EDUC 0.0003 0.0009 -0.0015 0.0021 0.34 0.7349
YEARSMA*AGEBASE*EDUC -0.0003 0.0019 -0.0040 0.0035 -0.14 0.8857
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
Full Model by Parent: CC - GEE: Type=UN
PARENT=1
Model Information
Data Set WORK.MARITCC
Distribution Binomial
Link Function Logit
Dependent Variable BSAT
Number of Observations Read 366
Number of Observations Used 366
Number of Events 340
Number of Trials 366
Class Level Information
Class Levels Values
DATASET 6. MARITAL SATISFACTION DATA 222
YEARCLS 3 1990 1995 2000
IDNR 122 24 26 40 48 78 84 92 94 102 112 120 130 134 136
138 140 146 160 196 248 250 278 286 288 314 332
340 342 346 362 364 374 386 412 416 424 426 434
440 444 448 454 456 470 480 506 510 520 548 552
558 566 578 598 622 626 630 640 644 646 662 664
674 682 696 ...
Response Profile
Ordered Total
Value BSAT Frequency
1 1 340
2 0 26
PROC GENMOD is modeling the probability that BSAT=’1’.
Parameter Information
Parameter Effect
Prm1 Intercept
Prm2 YEARSMAR90
Prm3 YEARSMAR90*YEAR
Prm4 YEARSMAR90*AGEBASE
Prm5 YEARSMAR90*EDUC
Prm6 YEARSMA*YEAR*AGEBASE
Prm7 YEARSMAR90*YEAR*EDUC
Prm8 YEARSMA*AGEBASE*EDUC
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 358 178.1734 0.4977
Scaled Deviance 358 178.1734 0.4977
Pearson Chi-Square 358 358.6836 1.0019
Scaled Pearson X2 358 358.6836 1.0019
Log Likelihood -89.0867
Algorithm converged.
Analysis Of Initial Parameter Estimates
Standard Wald 95% Chi-
Parameter DF Estimate Error Confidence Limits Square Pr > ChiSq
DATASET 6. MARITAL SATISFACTION DATA 223
Intercept 1 1.6766 1.9589 -2.1628 5.5160 0.73 0.3921
YEARSMAR90 1 -91.5897 63.2847 -215.625 32.4460 2.09 0.1478
YEARSMAR90*YEAR 1 0.0461 0.0317 -0.0160 0.1082 2.12 0.1457
YEARSMAR90*AGEBASE 1 2.4072 1.4827 -0.4989 5.3132 2.64 0.1045
YEARSMAR90*EDUC 1 -3.0702 3.6579 -10.2395 4.0991 0.70 0.4013
YEARSMA*YEAR*AGEBASE 1 -0.0012 0.0007 -0.0027 0.0002 2.66 0.1030
YEARSMAR90*YEAR*EDUC 1 0.0015 0.0018 -0.0021 0.0051 0.65 0.4193
YEARSMA*AGEBASE*EDUC 1 0.0023 0.0020 -0.0017 0.0063 1.32 0.2503
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
GEE Model Information
Correlation Structure Unstructured
Within-Subject Effect YEARCLS (3 levels)
Subject Effect IDNR (122 levels)
Number of Clusters 122
Correlation Matrix Dimension 3
Maximum Cluster Size 3
Minimum Cluster Size 3
Algorithm converged.
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 1.5132 2.0866 -2.5766 5.6029 0.73 0.4684
YEARSMAR90 -105.064 45.7407 -194.714 -15.4143 -2.30 0.0216
YEARSMAR90*YEAR 0.0528 0.0229 0.0080 0.0976 2.31 0.0209
YEARSMAR90*AGEBASE 2.7683 1.1125 0.5878 4.9488 2.49 0.0128
YEARSMAR90*EDUC -3.0568 3.5830 -10.0793 3.9656 -0.85 0.3936
YEARSMA*YEAR*AGEBASE -0.0014 0.0006 -0.0025 -0.0003 -2.50 0.0125
YEARSMAR90*YEAR*EDUC 0.0015 0.0018 -0.0020 0.0050 0.82 0.4098
YEARSMA*AGEBASE*EDUC 0.0021 0.0014 -0.0006 0.0048 1.53 0.1264
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 1.5132 2.3965 -3.1838 6.2101 0.63 0.5278
YEARSMAR90 -105.064 56.6281 -216.054 5.9247 -1.86 0.0635
YEARSMAR90*YEAR 0.0528 0.0283 -0.0027 0.1084 1.86 0.0623
YEARSMAR90*AGEBASE 2.7683 1.3447 0.1328 5.4038 2.06 0.0395
YEARSMAR90*EDUC -3.0568 3.2344 -9.3961 3.2824 -0.95 0.3446
DATASET 6. MARITAL SATISFACTION DATA 224
YEARSMA*YEAR*AGEBASE -0.0014 0.0007 -0.0027 -0.0001 -2.07 0.0387
YEARSMAR90*YEAR*EDUC 0.0015 0.0016 -0.0017 0.0047 0.91 0.3630
YEARSMA*AGEBASE*EDUC 0.0021 0.0024 -0.0027 0.0069 0.87 0.3865
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
Reduced Model for Males: CC - GEE: Type=UN
Model Information
Data Set WORK.MALES
Distribution Binomial
Link Function Logit
Dependent Variable BSAT
Number of Observations Read 366
Number of Observations Used 366
Number of Events 339
Number of Trials 366
Class Level Information
Class Levels Values
YEARCLS 3 1990 1995 2000
IDNR 122 23 25 39 47 77 83 91 93 101 111 119 129 133 135
137 139 145 159 195 247 249 277 285 287 313 331
339 341 345 361 363 373 385 411 415 423 425 433
439 443 447 453 455 469 479 505 509 519 547 551
557 565 577 597 621 625 629 639 643 645 661 663
673 681 695 ...
Response Profile
Ordered Total
Value BSAT Frequency
1 1 339
2 0 27
PROC GENMOD is modeling the probability that BSAT=’1’.
Parameter Information
Parameter Effect
Prm1 Intercept
DATASET 6. MARITAL SATISFACTION DATA 225
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 365 192.7243 0.5280
Scaled Deviance 365 192.7243 0.5280
Pearson Chi-Square 365 366.0000 1.0027
Scaled Pearson X2 365 366.0000 1.0027
Log Likelihood -96.3622
Algorithm converged.
Analysis Of Initial Parameter Estimates
Standard Wald 95% Confidence Chi-
Parameter DF Estimate Error Limits Square Pr > ChiSq
Intercept 1 2.5302 0.2000 2.1382 2.9221 160.10 <.0001
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
GEE Model Information
Correlation Structure Unstructured
Within-Subject Effect YEARCLS (3 levels)
Subject Effect IDNR (122 levels)
Number of Clusters 122
Correlation Matrix Dimension 3
Maximum Cluster Size 3
Minimum Cluster Size 3
Algorithm converged.
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 2.5333 0.2800 1.9845 3.0822 9.05 <.0001
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
DATASET 6. MARITAL SATISFACTION DATA 226
Intercept 2.5333 0.2803 1.9840 3.0827 9.04 <.0001
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
Reduced Model for Females: CC - GEE: Type=UN
Model Information
Data Set WORK.FEMALES
Distribution Binomial
Link Function Logit
Dependent Variable BSAT
Number of Observations Read 366
Number of Observations Used 366
Number of Events 340
Number of Trials 366
Class Level Information
Class Levels Values
YEARCLS 3 1990 1995 2000
IDNR 122 24 26 40 48 78 84 92 94 102 112 120 130 134 136
138 140 146 160 196 248 250 278 286 288 314 332
340 342 346 362 364 374 386 412 416 424 426 434
440 444 448 454 456 470 480 506 510 520 548 552
558 566 578 598 622 626 630 640 644 646 662 664
674 682 696 ...
Response Profile
Ordered Total
Value BSAT Frequency
1 1 340
2 0 26
PROC GENMOD is modeling the probability that BSAT=’1’.
Parameter Information
Parameter Effect
Prm1 Intercept
Prm2 YEARSMAR90
Prm3 YEARSMAR90*YEAR
DATASET 6. MARITAL SATISFACTION DATA 227
Prm4 YEARSMAR90*AGEBASE
Prm5 YEARSMAR90*EDUC
Prm6 YEARSMA*YEAR*AGEBASE
Prm7 YEARSMA*AGEBASE*EDUC
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 360 179.5951 0.4989
Scaled Deviance 360 179.5951 0.4989
Pearson Chi-Square 360 358.5169 0.9959
Scaled Pearson X2 360 358.5169 0.9959
Log Likelihood -89.7976
Algorithm converged.
Analysis Of Initial Parameter Estimates
Standard Wald 95% Chi-
Parameter DF Estimate Error Confidence Limits Square Pr > ChiSq
Intercept 0 0.0000 0.0000 0.0000 0.0000 . .
YEARSMAR90 1 -106.408 58.0239 -220.133 7.3170 3.36 0.0667
YEARSMAR90*YEAR 1 0.0537 0.0291 -0.0033 0.1106 3.41 0.0649
YEARSMAR90*AGEBASE 1 2.5085 1.4119 -0.2587 5.2758 3.16 0.0756
YEARSMAR90*EDUC 1 -0.1109 0.0761 -0.2600 0.0383 2.12 0.1452
YEARSMA*YEAR*AGEBASE 1 -0.0013 0.0007 -0.0026 0.0001 3.19 0.0741
YEARSMA*AGEBASE*EDUC 1 0.0025 0.0019 -0.0012 0.0062 1.75 0.1858
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
Lagrange Multiplier Statistics
Parameter Chi-Square Pr > ChiSq
Intercept 0.7457 0.3878
GEE Model Information
Correlation Structure Unstructured
Within-Subject Effect YEARCLS (3 levels)
Subject Effect IDNR (122 levels)
Number of Clusters 122
Correlation Matrix Dimension 3
Maximum Cluster Size 3
Minimum Cluster Size 3
DATASET 6. MARITAL SATISFACTION DATA 228
Algorithm converged.
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.0000 0.0000 0.0000 0.0000 . .
YEARSMAR90 -118.617 42.4646 -201.846 -35.3874 -2.79 0.0052
YEARSMAR90*YEAR 0.0598 0.0213 0.0180 0.1015 2.81 0.0050
YEARSMAR90*AGEBASE 2.8435 1.0403 0.8045 4.8824 2.73 0.0063
YEARSMAR90*EDUC -0.1069 0.0525 -0.2098 -0.0040 -2.04 0.0417
YEARSMA*YEAR*AGEBASE -0.0014 0.0005 -0.0025 -0.0004 -2.74 0.0061
YEARSMA*AGEBASE*EDUC 0.0024 0.0013 -0.0001 0.0048 1.87 0.0614
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.0000 0.0000 0.0000 0.0000 . .
YEARSMAR90 -118.617 52.3178 -221.158 -16.0755 -2.27 0.0234
YEARSMAR90*YEAR 0.0598 0.0262 0.0084 0.1111 2.28 0.0225
YEARSMAR90*AGEBASE 2.8435 1.2746 0.3453 5.3416 2.23 0.0257
YEARSMAR90*EDUC -0.1069 0.0890 -0.2813 0.0675 -1.20 0.2296
YEARSMA*YEAR*AGEBASE -0.0014 0.0006 -0.0027 -0.0002 -2.24 0.0250
YEARSMA*AGEBASE*EDUC 0.0024 0.0022 -0.0019 0.0067 1.08 0.2803
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
2. Joint Analysis
CC - GEE: Full Model: Type=UN
Model Information
Data Set WORK.MARITCC
Distribution Binomial
Link Function Logit
Dependent Variable BSAT
Number of Observations Read 732
Number of Observations Used 732
Number of Events 679
Number of Trials 732
Class Level Information
DATASET 6. MARITAL SATISFACTION DATA 229
Class Levels Values
FAMNR 122 95 96 116 129 281 299 324 331 349 364 380 402 405
415 421 423 438 547 627 1076 1087 1151 1181 1182
1253 1314 1329 1332 1339 1375 1382 1422 1476 1523
1557 1566 1571 1606 1611 1614 1617 1637 1640 1680
1700 1761 1767 1783 1939 1950 1962 2008 2023 2079
...
YEARCLS 3 1990 1995 2000
PARENTCLS 2 0 1
Response Profile
Ordered Total
Value BSAT Frequency
1 1 679
2 0 53
PROC GENMOD is modeling the probability that BSAT=’1’.
Parameter Information
Parameter Effect
Prm1 Intercept
Prm2 PARENT*YEARSMAR90
Prm3 PARENT*YEARSMAR*YEAR
Prm4 PARENT*YEARSM*AGEBAS
Prm5 PARENT*YEARSMAR*EDUC
Prm6 PARE*YEAR*YEAR*AGEBA
Prm7 PARE*YEARS*YEAR*EDUC
Prm8 PARE*YEAR*AGEBA*EDUC
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 724 371.0826 0.5125
Scaled Deviance 724 371.0826 0.5125
Pearson Chi-Square 724 722.3190 0.9977
Scaled Pearson X2 724 722.3190 0.9977
Log Likelihood -185.5413
Algorithm converged.
Analysis Of Initial Parameter Estimates
DATASET 6. MARITAL SATISFACTION DATA 230
Standard Wald 95% Chi-
Parameter DF Estimate Error Confidence Limits Square Pr > ChiSq
Intercept 1 2.5216 0.1983 2.1330 2.9102 161.75 <.0001
PARENT*YEARSMAR90 1 -92.5206 63.4805 -216.940 31.8988 2.12 0.1450
PARENT*YEARSMAR*YEAR 1 0.0465 0.0318 -0.0158 0.1088 2.14 0.1434
PARENT*YEARSM*AGEBAS 1 2.4290 1.4893 -0.4900 5.3480 2.66 0.1029
PARENT*YEARSMAR*EDUC 1 -3.0624 3.6483 -10.2129 4.0880 0.70 0.4012
PARE*YEAR*YEAR*AGEBA 1 -0.0012 0.0007 -0.0027 0.0002 2.68 0.1016
PARE*YEARS*YEAR*EDUC 1 0.0015 0.0018 -0.0021 0.0051 0.65 0.4201
PARE*YEAR*AGEBA*EDUC 1 0.0025 0.0021 -0.0016 0.0065 1.42 0.2332
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
GEE Model Information
Correlation Structure Unstructured
Within-Subject Effect YEARCLS(PARENTCLS) (6 levels)
Subject Effect FAMNR (122 levels)
Number of Clusters 122
Correlation Matrix Dimension 6
Maximum Cluster Size 6
Minimum Cluster Size 6
Algorithm converged.
Working Correlation Matrix
Col1 Col2 Col3 Col4 Col5 Col6
Row1 1.0000 0.4392 0.5290 0.1111 0.1343 0.0526
Row2 0.4392 1.0000 0.5777 0.1495 0.2695 0.2196
Row3 0.5290 0.5777 1.0000 0.2880 0.2219 0.3311
Row4 0.1111 0.1495 0.2880 1.0000 0.2834 0.2212
Row5 0.1343 0.2695 0.2219 0.2834 1.0000 0.4382
Row6 0.0526 0.2196 0.3311 0.2212 0.4382 1.0000
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 2.5021 0.2724 1.9683 3.0360 9.19 <.0001
PARENT*YEARSMAR90 -112.543 41.2309 -193.354 -31.7318 -2.73 0.0063
PARENT*YEARSMAR*YEAR 0.0565 0.0206 0.0160 0.0969 2.73 0.0063
PARENT*YEARSM*AGEBAS 2.9083 1.0653 0.8203 4.9963 2.73 0.0063
PARENT*YEARSMAR*EDUC -2.2856 3.1255 -8.4114 3.8402 -0.73 0.4646
PARE*YEAR*YEAR*AGEBA -0.0015 0.0005 -0.0025 -0.0004 -2.74 0.0062
DATASET 6. MARITAL SATISFACTION DATA 231
PARE*YEARS*YEAR*EDUC 0.0011 0.0016 -0.0020 0.0042 0.71 0.4757
PARE*YEAR*AGEBA*EDUC 0.0007 0.0012 -0.0017 0.0031 0.59 0.5526
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 2.5021 0.2797 1.9540 3.0503 8.95 <.0001
PARENT*YEARSMAR90 -112.543 52.3981 -215.241 -9.8443 -2.15 0.0317
PARENT*YEARSMAR*YEAR 0.0565 0.0262 0.0050 0.1079 2.15 0.0314
PARENT*YEARSM*AGEBAS 2.9083 1.2660 0.4270 5.3895 2.30 0.0216
PARENT*YEARSMAR*EDUC -2.2856 2.9466 -8.0607 3.4896 -0.78 0.4379
PARE*YEAR*YEAR*AGEBA -0.0015 0.0006 -0.0027 -0.0002 -2.30 0.0214
PARE*YEARS*YEAR*EDUC 0.0011 0.0015 -0.0018 0.0040 0.76 0.4499
PARE*YEAR*AGEBA*EDUC 0.0007 0.0018 -0.0029 0.0043 0.40 0.6925
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
CC - GEE: Reduced Model: Type=UN
Model Information
Data Set WORK.MARITCC
Distribution Binomial
Link Function Logit
Dependent Variable BSAT
Number of Observations Read 732
Number of Observations Used 732
Number of Events 679
Number of Trials 732
Class Level Information
Class Levels Values
FAMNR 122 95 96 116 129 281 299 324 331 349 364 380 402 405
415 421 423 438 547 627 1076 1087 1151 1181 1182
1253 1314 1329 1332 1339 1375 1382 1422 1476 1523
1557 1566 1571 1606 1611 1614 1617 1637 1640 1680
1700 1761 1767 1783 1939 1950 1962 2008 2023 2079
...
YEARCLS 3 1990 1995 2000
PARENTCLS 2 0 1
Response Profile
DATASET 6. MARITAL SATISFACTION DATA 232
Ordered Total
Value BSAT Frequency
1 1 679
2 0 53
PROC GENMOD is modeling the probability that BSAT=’1’.
Parameter Information
Parameter Effect
Prm1 Intercept
Prm2 PARENT*YEARSMAR90
Prm3 PARENT*YEARSMAR*YEAR
Prm4 PARENT*YEARSM*AGEBAS
Prm5 PARENT*YEARSMAR*EDUC
Prm6 PARE*YEAR*YEAR*AGEBA
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 726 374.1287 0.5153
Scaled Deviance 726 374.1287 0.5153
Pearson Chi-Square 726 722.5451 0.9952
Scaled Pearson X2 726 722.5451 0.9952
Log Likelihood -187.0644
Algorithm converged.
Analysis Of Initial Parameter Estimates
Standard Wald 95% Chi-
Parameter DF Estimate Error Confidence Limits Square Pr > ChiSq
Intercept 1 2.5189 0.1980 2.1309 2.9070 161.88 <.0001
PARENT*YEARSMAR90 1 -118.313 58.4154 -232.805 -3.8211 4.10 0.0428
PARENT*YEARSMAR*YEAR 1 0.0593 0.0293 0.0019 0.1167 4.10 0.0428
PARENT*YEARSM*AGEBAS 1 2.8050 1.4207 0.0205 5.5895 3.90 0.0483
PARENT*YEARSMAR*EDUC 1 -0.0106 0.0068 -0.0238 0.0027 2.44 0.1183
PARE*YEAR*YEAR*AGEBA 1 -0.0014 0.0007 -0.0028 -0.0000 3.90 0.0484
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
GEE Model Information
DATASET 6. MARITAL SATISFACTION DATA 233
Correlation Structure Unstructured
Within-Subject Effect YEARCLS(PARENTCLS) (6 levels)
Subject Effect FAMNR (122 levels)
Number of Clusters 122
Correlation Matrix Dimension 6
Maximum Cluster Size 6
Minimum Cluster Size 6
Algorithm converged.
Working Correlation Matrix
Col1 Col2 Col3 Col4 Col5 Col6
Row1 1.0000 0.4364 0.5257 0.1450 0.1390 0.0496
Row2 0.4364 1.0000 0.5740 0.1604 0.2665 0.2274
Row3 0.5257 0.5740 1.0000 0.2991 0.2201 0.3330
Row4 0.1450 0.1604 0.2991 1.0000 0.2805 0.2140
Row5 0.1390 0.2665 0.2201 0.2805 1.0000 0.4443
Row6 0.0496 0.2274 0.3330 0.2140 0.4443 1.0000
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 2.5045 0.2734 1.9687 3.0404 9.16 <.0001
PARENT*YEARSMAR90 -123.410 41.0496 -203.866 -42.9542 -3.01 0.0026
PARENT*YEARSMAR*YEAR 0.0619 0.0206 0.0215 0.1022 3.01 0.0026
PARENT*YEARSM*AGEBAS 2.9838 0.9950 1.0336 4.9340 3.00 0.0027
PARENT*YEARSMAR*EDUC -0.0119 0.0076 -0.0268 0.0030 -1.56 0.1184
PARE*YEAR*YEAR*AGEBA -0.0015 0.0005 -0.0025 -0.0005 -3.00 0.0027
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 2.5045 0.2796 1.9565 3.0526 8.96 <.0001
PARENT*YEARSMAR90 -123.410 50.4685 -222.326 -24.4934 -2.45 0.0145
PARENT*YEARSMAR*YEAR 0.0619 0.0253 0.0123 0.1114 2.45 0.0144
PARENT*YEARSM*AGEBAS 2.9838 1.2255 0.5819 5.3857 2.43 0.0149
PARENT*YEARSMAR*EDUC -0.0119 0.0074 -0.0265 0.0027 -1.59 0.1110
PARE*YEAR*YEAR*AGEBA -0.0015 0.0006 -0.0027 -0.0003 -2.44 0.0149
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
DATASET 6. MARITAL SATISFACTION DATA 234
Part 3
1. Nested random effects - PQL under REML:
Model Information
Data Set WORK.DAT
Response Variable bsat
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By FAMNR
Estimation Technique Residual PL
Degrees of Freedom Method Containment
Number of Observations Read 3438
Number of Observations Used 2102
Response Profile
Ordered Total
Value bsat Frequency
1 0 209
2 1 1893
The GLIMMIX procedure is modeling the probability that bsat=’1’.
Dimensions
G-side Cov. Parameters 2
Columns in X 14
Columns in Z per Subject 3
Subjects (Blocks in V) 573
Max Obs per Subject 6
Optimization Information
Optimization Technique Dual Quasi-Newton
Parameters in Optimization 2
Lower Boundaries 2
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
Convergence criterion (PCONV=1.11022E-8) satisfied.
Estimated G matrix is not positive definite.
Fit Statistics
-2 Res Log Pseudo-Likelihood 10792.94
Generalized Chi-Square 997.90
Gener. Chi-Square / DF 0.48
DATASET 6. MARITAL SATISFACTION DATA 235
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
Intercept FAMNR 1.6640 0.2396
Intercept PARENT(FAMNR) 6.34E-18 .
Solutions for Fixed Effects
Standard
Effect PARENT YEAR Estimate Error DF t Value Pr > |t|
Intercept 3.0527 0.8803 558 3.47 0.0006
YEAR 1990 -0.6198 0.4397 964 -1.41 0.1590
YEAR 1995 0.3469 0.4058 964 0.85 0.3928
YEAR 2000 0 . . . .
PARENT 0 0.1369 0.4310 558 0.32 0.7509
PARENT 1 0 . . . .
PARENT*YEAR 0 1990 -0.03129 0.4723 964 -0.07 0.9472
PARENT*YEAR 0 1995 -0.2938 0.5409 964 -0.54 0.5871
PARENT*YEAR 0 2000 0 . . . .
PARENT*YEAR 1 1990 0 . . . .
PARENT*YEAR 1 1995 0 . . . .
PARENT*YEAR 1 2000 0 . . . .
CHILD 0.08389 0.09584 964 0.88 0.3816
yearsmarr -0.02938 0.02956 964 -0.99 0.3205
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 2 964 5.91 0.0028
PARENT 1 558 0.02 0.8818
PARENT*YEAR 2 964 0.26 0.7695
CHILD 1 964 0.77 0.3816
yearsmarr 1 964 0.99 0.3205
2. Nested random effects - MQL under REML:
Model Information
Data Set WORK.DAT
Response Variable bsat
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By FAMNR
Estimation Technique Residual MPL
Degrees of Freedom Method Containment
Number of Observations Read 3438
Number of Observations Used 2102
DATASET 6. MARITAL SATISFACTION DATA 236
Response Profile
Ordered Total
Value bsat Frequency
1 0 209
2 1 1893
The GLIMMIX procedure is modeling the probability that bsat=’1’.
Dimensions
G-side Cov. Parameters 2
Columns in X 14
Columns in Z per Subject 3
Subjects (Blocks in V) 573
Max Obs per Subject 6
Optimization Information
Optimization Technique Dual Quasi-Newton
Parameters in Optimization 2
Lower Boundaries 2
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
Convergence criterion (PCONV=1.11022E-8) satisfied.
Estimated G matrix is not positive definite.
Fit Statistics
-2 Res Log Pseudo-Likelihood 10897.09
Generalized Chi-Square 1597.34
Gener. Chi-Square / DF 0.76
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
Intercept FAMNR 2.3957 0.3247
Intercept PARENT(FAMNR) 2.36E-18 .
Solutions for Fixed Effects
Standard
Effect PARENT YEAR Estimate Error DF t Value Pr > |t|
Intercept 2.8528 0.8596 558 3.32 0.0010
YEAR 1990 -0.5461 0.4179 964 -1.31 0.1916
YEAR 1995 0.3003 0.3751 964 0.80 0.4236
DATASET 6. MARITAL SATISFACTION DATA 237
YEAR 2000 0 . . . .
PARENT 0 0.1212 0.3880 558 0.31 0.7549
PARENT 1 0 . . . .
PARENT*YEAR 0 1990 -0.02857 0.4288 964 -0.07 0.9469
PARENT*YEAR 0 1995 -0.2657 0.4914 964 -0.54 0.5889
PARENT*YEAR 0 2000 0 . . . .
PARENT*YEAR 1 1990 0 . . . .
PARENT*YEAR 1 1995 0 . . . .
PARENT*YEAR 1 2000 0 . . . .
CHILD 0.06638 0.09408 964 0.71 0.4806
yearsmarr -0.03084 0.02935 964 -1.05 0.2936
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 2 964 4.99 0.0070
PARENT 1 558 0.02 0.8950
PARENT*YEAR 2 964 0.25 0.7786
CHILD 1 964 0.50 0.4806
yearsmarr 1 964 1.10 0.2936
3. Nested random effects - Adaptive Gauss Hermite:
Specifications
Data Set WORK.DAT
Dependent Variable bsat
Distribution for Dependent Variable Binary
Random Effects g1 g2
Distribution for Random Effects Normal
Subject Variable FAMNR
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 2102
Observations Not Used 1336
Total Observations 3438
Subjects 573
Max Obs Per Subject 6
Parameters 10
Quadrature Points 10
Parameters
b0 b1 b2 b3 b4 b5 b6 b7 V1 V2
2.8528 -0.5461 0.3003 0.1212 -0.02857 -0.2657 0.06638 -0.03084 2.3957 1
NegLogLike
DATASET 6. MARITAL SATISFACTION DATA 238
668.813909
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 623.175172 45.63874 347.5408 -36275.4
2 5 618.372171 4.803001 24.9271 -7.84723
3 7 614.795292 3.576879 321.8137 -2.30974
4 9 605.846345 8.948948 22.89988 -3.58245
5 11 603.694606 2.151738 89.56562 -1.464
6 12 602.628206 1.066401 32.77747 -0.83238
7 13 601.97919 0.649016 16.91893 -1.43408
8 14 601.665098 0.314092 33.32883 -0.72667
9 15 601.208274 0.456824 9.661278 -0.61331
10 16 600.792377 0.415896 9.710633 -0.26597
11 18 600.615128 0.17725 1.659908 -0.26523
12 20 600.543975 0.071153 3.595091 -0.03407
13 22 600.175591 0.368385 20.66025 -0.07906
14 24 600.05314 0.122451 16.58005 -0.13738
15 26 599.99982 0.05332 2.320657 -0.07341
16 28 599.976771 0.023049 13.13735 -0.01359
17 30 599.924682 0.052088 13.35125 -0.02512
18 32 599.911162 0.01352 1.259838 -0.0205
19 34 599.908848 0.002315 0.994878 -0.00189
20 36 599.888726 0.020122 5.835654 -0.00316
21 38 599.845863 0.042863 2.997486 -0.02204
22 40 599.822665 0.023198 0.502865 -0.02128
23 42 599.81846 0.004205 0.280123 -0.00608
24 44 599.818405 0.000055 0.088641 -0.00009
25 46 599.818035 0.000371 0.179494 -0.00002
26 47 599.817587 0.000447 0.048878 -0.0004
27 49 599.817586 1.342E-6 0.002676 -2.7E-6
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 1199.6
AIC (smaller is better) 1219.6
AICC (smaller is better) 1219.7
BIC (smaller is better) 1263.1
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
b0 4.6847 1.3678 571 3.42 0.0007 0.05 1.9981 7.3712 0.000124
b1 -0.7946 0.6029 571 -1.32 0.1880 0.05 -1.9788 0.3895 0.000121
b2 0.4935 0.5058 571 0.98 0.3297 0.05 -0.5000 1.4869 -0.00008
b3 0.2228 0.5265 571 0.42 0.6722 0.05 -0.8112 1.2569 0.000025
b4 -0.06166 0.5684 571 -0.11 0.9136 0.05 -1.1780 1.0547 7.725E-6
b5 -0.4096 0.6436 571 -0.64 0.5248 0.05 -1.6738 0.8546 -0.00003
DATASET 6. MARITAL SATISFACTION DATA 239
b6 0.1700 0.1487 571 1.14 0.2536 0.05 -0.1221 0.4620 0.000303
b7 -0.04985 0.04586 571 -1.09 0.2775 0.05 -0.1399 0.04023 0.002676
V1 0.9007 0.6175 571 1.46 0.1452 0.05 -0.3122 2.1135 -0.00006
V2 5.0277 1.1089 571 4.53 <.0001 0.05 2.8498 7.2057 -0.00002
4. Test for the parent RE:
Specifications
Data Set WORK.DAT
Dependent Variable bsat
Distribution for Dependent Variable Binary
Random Effects g1
Distribution for Random Effects Normal
Subject Variable FAMNR
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 2102
Observations Not Used 1336
Total Observations 3438
Subjects 573
Max Obs Per Subject 6
Parameters 9
Quadrature Points 10
Parameters
b0 b1 b2 b3 b4 b5 b6 b7 V1 NegLogLike
2.8528 -0.5461 0.3003 0.1212 -0.02857 -0.2657 0.06638 -0.03084 2.3957 656.61496
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 607.195256 49.4197 54.36621 -20610.7
2 5 603.970472 3.224784 44.41349 -5.25338
3 7 603.145232 0.82524 19.90867 -0.9741
4 9 602.464818 0.680414 22.54237 -0.59021
5 11 602.283024 0.181794 21.38663 -0.21632
6 13 602.186664 0.09636 7.665615 -0.09384
7 15 602.124647 0.062017 17.10094 -0.04093
8 16 602.038507 0.08614 5.669192 -0.05049
9 18 602.005751 0.032756 1.03675 -0.02963
10 19 601.949704 0.056046 6.688754 -0.02942
11 20 601.881805 0.0679 3.206596 -0.0567
12 21 601.763532 0.118273 0.73193 -0.06214
13 23 601.731248 0.032283 1.728933 -0.05459
14 24 601.676946 0.054303 2.192901 -0.00995
15 26 601.665972 0.010974 0.21346 -0.02043
16 28 601.631547 0.034425 5.698429 -0.00125
DATASET 6. MARITAL SATISFACTION DATA 240
17 29 601.606951 0.024595 0.439586 -0.03079
18 31 601.601369 0.005582 0.075129 -0.01109
19 33 601.601368 5.824E-7 0.000131 -1.16E-6
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 1203.2
AIC (smaller is better) 1221.2
AICC (smaller is better) 1221.3
BIC (smaller is better) 1260.4
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
b0 4.3240 1.2469 572 3.47 0.0006 0.05 1.8750 6.7730 5.133E-6
b1 -0.7547 0.5636 572 -1.34 0.1811 0.05 -1.8617 0.3523 -0.00002
b2 0.4557 0.4792 572 0.95 0.3420 0.05 -0.4855 1.3969 0.000053
b3 0.1510 0.4817 572 0.31 0.7540 0.05 -0.7952 1.0972 0.000014
b4 -0.02026 0.5307 572 -0.04 0.9696 0.05 -1.0627 1.0221 -0.00003
b5 -0.3706 0.6054 572 -0.61 0.5407 0.05 -1.5596 0.8184 0.000059
b6 0.1519 0.1371 572 1.11 0.2684 0.05 -0.1174 0.4211 -1E-5
b7 -0.04526 0.04224 572 -1.07 0.2844 0.05 -0.1282 0.03770 -0.00013
V1 2.1158 0.2082 572 10.16 <.0001 0.05 1.7069 2.5247 0.000019
Obs logL0 logL1 LRT df pval
1 -601.6 -599.8 3.6 1 0.057780
5. PQL under REML:
Model Information
Data Set WORK.DAT
Response Variable bsat
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By FAMNR
Estimation Technique Residual PL
Degrees of Freedom Method Containment
Number of Observations Read 3438
Number of Observations Used 2102
Response Profile
Ordered Total
Value bsat Frequency
DATASET 6. MARITAL SATISFACTION DATA 241
1 0 209
2 1 1893
The GLIMMIX procedure is modeling the probability that bsat=’1’.
Dimensions
G-side Cov. Parameters 1
Columns in X 14
Columns in Z per Subject 1
Subjects (Blocks in V) 573
Max Obs per Subject 6
Optimization Information
Optimization Technique Newton-Raphson
Parameters in Optimization 1
Lower Boundaries 1
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Res Log Pseudo-Likelihood 10792.94
Generalized Chi-Square 997.90
Gener. Chi-Square / DF 0.48
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
Intercept FAMNR 1.6640 0.2396
Solutions for Fixed Effects
Standard
Effect PARENT YEAR Estimate Error DF t Value Pr > |t|
Intercept 3.0527 0.8803 572 3.47 0.0006
YEAR 1990 -0.6198 0.4397 1522 -1.41 0.1588
YEAR 1995 0.3469 0.4058 1522 0.85 0.3927
YEAR 2000 0 . . . .
PARENT 0 0.1369 0.4310 1522 0.32 0.7509
PARENT 1 0 . . . .
PARENT*YEAR 0 1990 -0.03129 0.4723 1522 -0.07 0.9472
PARENT*YEAR 0 1995 -0.2938 0.5409 1522 -0.54 0.5870
PARENT*YEAR 0 2000 0 . . . .
PARENT*YEAR 1 1990 0 . . . .
PARENT*YEAR 1 1995 0 . . . .
PARENT*YEAR 1 2000 0 . . . .
DATASET 6. MARITAL SATISFACTION DATA 242
CHILD 0.08389 0.09584 1522 0.88 0.3816
yearsmarr -0.02938 0.02956 1522 -0.99 0.3205
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 2 1522 5.91 0.0028
PARENT 1 1522 0.02 0.8818
PARENT*YEAR 2 1522 0.26 0.7695
CHILD 1 1522 0.77 0.3816
yearsmarr 1 1522 0.99 0.3205
6. PQL under ML:
Model Information
Data Set WORK.DAT
Response Variable bsat
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By FAMNR
Estimation Technique PL
Degrees of Freedom Method Containment
Number of Observations Read 3438
Number of Observations Used 2102
Response Profile
Ordered Total
Value bsat Frequency
1 0 209
2 1 1893
The GLIMMIX procedure is modeling the probability that bsat=’1’.
Dimensions
G-side Cov. Parameters 1
Columns in X 14
Columns in Z per Subject 1
Subjects (Blocks in V) 573
Max Obs per Subject 6
Optimization Information
Optimization Technique Newton-Raphson
Parameters in Optimization 1
Lower Boundaries 1
DATASET 6. MARITAL SATISFACTION DATA 243
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Log Pseudo-Likelihood 10771.23
Generalized Chi-Square 1001.86
Gener. Chi-Square / DF 0.48
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
Intercept FAMNR 1.6390 0.2370
Solutions for Fixed Effects
Standard
Effect PARENT YEAR Estimate Error DF t Value Pr > |t|
Intercept 3.0495 0.8773 572 3.48 0.0005
YEAR 1990 -0.6196 0.4387 1522 -1.41 0.1580
YEAR 1995 0.3456 0.4052 1522 0.85 0.3937
YEAR 2000 0 . . . .
PARENT 0 0.1369 0.4306 1522 0.32 0.7506
PARENT 1 0 . . . .
PARENT*YEAR 0 1990 -0.03138 0.4718 1522 -0.07 0.9470
PARENT*YEAR 0 1995 -0.2932 0.5403 1522 -0.54 0.5874
PARENT*YEAR 0 2000 0 . . . .
PARENT*YEAR 1 1990 0 . . . .
PARENT*YEAR 1 1995 0 . . . .
PARENT*YEAR 1 2000 0 . . . .
CHILD 0.08341 0.09547 1522 0.87 0.3824
yearsmarr -0.02932 0.02946 1522 -1.00 0.3196
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 2 1522 5.92 0.0028
PARENT 1 1522 0.02 0.8809
PARENT*YEAR 2 1522 0.26 0.7701
CHILD 1 1522 0.76 0.3824
yearsmarr 1 1522 0.99 0.3196
7. MQL under REML:
Model Information
Data Set WORK.DAT
DATASET 6. MARITAL SATISFACTION DATA 244
Response Variable bsat
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By FAMNR
Estimation Technique Residual MPL
Degrees of Freedom Method Containment
Number of Observations Read 3438
Number of Observations Used 2102
Response Profile
Ordered Total
Value bsat Frequency
1 0 209
2 1 1893
The GLIMMIX procedure is modeling the probability that bsat=’1’.
Dimensions
G-side Cov. Parameters 1
Columns in X 14
Columns in Z per Subject 1
Subjects (Blocks in V) 573
Max Obs per Subject 6
Optimization Information
Optimization Technique Dual Quasi-Newton
Parameters in Optimization 1
Lower Boundaries 1
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Res Log Pseudo-Likelihood 10897.09
Generalized Chi-Square 1597.34
Gener. Chi-Square / DF 0.76
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
Intercept FAMNR 2.3957 0.3247
DATASET 6. MARITAL SATISFACTION DATA 245
Solutions for Fixed Effects
Standard
Effect PARENT YEAR Estimate Error DF t Value Pr > |t|
Intercept 2.8528 0.8596 572 3.32 0.0010
YEAR 1990 -0.5461 0.4179 1522 -1.31 0.1915
YEAR 1995 0.3003 0.3751 1522 0.80 0.4235
YEAR 2000 0 . . . .
PARENT 0 0.1212 0.3880 1522 0.31 0.7549
PARENT 1 0 . . . .
PARENT*YEAR 0 1990 -0.02857 0.4288 1522 -0.07 0.9469
PARENT*YEAR 0 1995 -0.2657 0.4914 1522 -0.54 0.5888
PARENT*YEAR 0 2000 0 . . . .
PARENT*YEAR 1 1990 0 . . . .
PARENT*YEAR 1 1995 0 . . . .
PARENT*YEAR 1 2000 0 . . . .
CHILD 0.06638 0.09408 1522 0.71 0.4806
yearsmarr -0.03084 0.02935 1522 -1.05 0.2935
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 2 1522 4.99 0.0069
PARENT 1 1522 0.02 0.8950
PARENT*YEAR 2 1522 0.25 0.7785
CHILD 1 1522 0.50 0.4806
yearsmarr 1 1522 1.10 0.2935
8. MQL under ML:
Model Information
Data Set WORK.DAT
Response Variable bsat
Response Distribution Binary
Link Function Logit
Variance Function Default
Variance Matrix Blocked By FAMNR
Estimation Technique MPL
Degrees of Freedom Method Containment
Number of Observations Read 3438
Number of Observations Used 2102
Response Profile
Ordered Total
Value bsat Frequency
DATASET 6. MARITAL SATISFACTION DATA 246
1 0 209
2 1 1893
The GLIMMIX procedure is modeling the probability that bsat=’1’.
Dimensions
G-side Cov. Parameters 1
Columns in X 14
Columns in Z per Subject 1
Subjects (Blocks in V) 573
Max Obs per Subject 6
Optimization Information
Optimization Technique Dual Quasi-Newton
Parameters in Optimization 1
Lower Boundaries 1
Upper Boundaries 0
Fixed Effects Profiled
Starting From Data
Convergence criterion (PCONV=1.11022E-8) satisfied.
Fit Statistics
-2 Log Pseudo-Likelihood 10882.04
Generalized Chi-Square 1600.74
Gener. Chi-Square / DF 0.76
Covariance Parameter Estimates
Standard
Cov Parm Subject Estimate Error
Intercept FAMNR 2.3662 0.3220
Solutions for Fixed Effects
Standard
Effect PARE YEAR Estimate Error DF t Value Pr > |t|
Intercept 2.8528 0.8575 572 3.33 0.0009
YEAR 1990 -0.5465 0.4174 1522 -1.31 0.1906
YEAR 1995 0.3001 0.3750 1522 0.80 0.4236
YEAR 2000 0 . . . .
PARENT 0 0.1213 0.3881 1522 0.31 0.7546
PARENT 1 0 . . . .
PARENT*YEAR 0 1990 -0.02867 0.4289 1522 -0.07 0.9467
PARENT*YEAR 0 1995 -0.2656 0.4915 1522 -0.54 0.5890
PARENT*YEAR 0 2000 0 . . . .
DATASET 6. MARITAL SATISFACTION DATA 247
PARENT*YEAR 1 1990 0 . . . .
PARENT*YEAR 1 1995 0 . . . .
PARENT*YEAR 1 2000 0 . . . .
CHILD 0.06617 0.09384 1522 0.71 0.4808
yearsmarr -0.03079 0.02927 1522 -1.05 0.2930
Type III Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 2 1522 5.00 0.0069
PARENT 1 1522 0.02 0.8942
PARENT*YEAR 2 1522 0.25 0.7788
CHILD 1 1522 0.50 0.4808
yearsmarr 1 1522 1.11 0.2930
9. Gauss-Hermite quadrature method:Quadrature points 20
Specifications
Data Set WORK.DAT
Dependent Variable bsat
Distribution for Dependent Variable Binary
Random Effects g1
Distribution for Random Effects Normal
Subject Variable FAMNR
Optimization Technique Dual Quasi-Newton
Integration Method Gaussian Quadrature
Dimensions
Observations Used 2102
Observations Not Used 1336
Total Observations 3438
Subjects 573
Max Obs Per Subject 6
Parameters 9
Quadrature Points 20
Parameters
b0 b1 b2 b3 b4 b5 b6 b7 V1 NegLogLike
2.8528 -0.5465 0.3001 0.1213 -0.02867 -0.2656 0.06617 -0.03079 2.3662 655.301943
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 606.617711 48.68423 53.29391 -20839.3
2 5 603.642061 2.975649 36.4491 -4.99921
3 7 602.894991 0.747071 13.5725 -0.74237
DATASET 6. MARITAL SATISFACTION DATA 248
4 9 602.269373 0.625618 12.21121 -0.47682
5 11 602.090493 0.17888 29.34825 -0.12393
6 13 602.042601 0.047892 11.49444 -0.05899
7 15 601.935339 0.107262 5.266845 -0.0396
8 17 601.883304 0.052035 9.171713 -0.03022
9 18 601.845179 0.038125 1.341823 -0.03418
10 19 601.789902 0.055277 2.722201 -0.04462
11 21 601.642531 0.147371 1.384209 -0.05951
12 23 601.599932 0.042599 1.510803 -0.05877
13 24 601.539909 0.060023 0.47715 -0.01021
14 26 601.530733 0.009176 0.24404 -0.01563
15 27 601.521776 0.008957 0.361106 -0.00141
16 29 601.481188 0.040588 0.585063 -0.01702
17 31 601.463088 0.0181 0.038528 -0.02317
18 33 601.463083 4.828E-6 0.006037 -0.00001
19 35 601.463083 2.319E-8 0.000212 -4.63E-8
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 1202.9
AIC (smaller is better) 1220.9
AICC (smaller is better) 1221.0
BIC (smaller is better) 1260.1
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
b0 4.3539 1.2535 572 3.47 0.0006 0.05 1.8920 6.8159 0.00002
b1 -0.7591 0.5643 572 -1.35 0.1791 0.05 -1.8674 0.3492 0.000031
b2 0.4569 0.4796 572 0.95 0.3412 0.05 -0.4852 1.3989 -7.42E-6
b3 0.1508 0.4824 572 0.31 0.7548 0.05 -0.7968 1.0983 4.646E-6
b4 -0.01974 0.5316 572 -0.04 0.9704 0.05 -1.0638 1.0243 0.000014
b5 -0.3720 0.6064 572 -0.61 0.5398 0.05 -1.5630 0.8189 -3.85E-6
b6 0.1530 0.1364 572 1.12 0.2625 0.05 -0.1149 0.4209 0.000035
b7 -0.04562 0.04241 572 -1.08 0.2825 0.05 -0.1289 0.03768 0.000212
V1 2.1419 0.2178 572 9.84 <.0001 0.05 1.7142 2.5697 -9.55E-6
10. Adaptive Gauss-Hermite quadrature method:Quadrature points 20
Specifications
Data Set WORK.DAT
Dependent Variable bsat
Distribution for Dependent Variable Binary
Random Effects g1
Distribution for Random Effects Normal
Subject Variable FAMNR
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
DATASET 6. MARITAL SATISFACTION DATA 249
Quadrature
Dimensions
Observations Used 2102
Observations Not Used 1336
Total Observations 3438
Subjects 573
Max Obs Per Subject 6
Parameters 9
Quadrature Points 20
Parameters
b0 b1 b2 b3 b4 b5 b6 b7 V1 NegLogLike
2.8528 -0.5465 0.3001 0.1213 -0.02867 -0.2656 0.06617 -0.03079 2.3662 655.478125
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 606.687032 48.79109 59.31878 -20769.3
2 5 603.687591 2.99944 37.88727 -4.97779
3 7 602.974451 0.71314 20.75368 -0.77795
4 9 602.339803 0.634648 20.77356 -0.48552
5 11 602.170863 0.16894 22.67167 -0.16091
6 13 602.090426 0.080437 2.310172 -0.08521
7 14 601.991847 0.098579 18.31438 -0.02939
8 16 601.948716 0.043131 12.91512 -0.04565
9 17 601.891331 0.057385 3.359225 -0.0295
10 18 601.791255 0.100076 7.200366 -0.02416
11 19 601.680281 0.110974 9.308333 -0.13945
12 21 601.654022 0.026259 2.466996 -0.03148
13 22 601.610985 0.043037 0.596406 -0.01201
14 24 601.588483 0.022502 0.609329 -0.03361
15 26 601.585733 0.00275 0.747981 -0.00243
16 29 601.524155 0.061578 4.385252 -0.0024
17 31 601.521304 0.002852 0.051081 -0.00561
18 33 601.5213 3.258E-6 0.003112 -6.43E-6
19 35 601.5213 1.78E-9 0.000086 -3.64E-9
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 1203.0
AIC (smaller is better) 1221.0
AICC (smaller is better) 1221.1
BIC (smaller is better) 1260.2
Parameter Estimates
Standard
DATASET 6. MARITAL SATISFACTION DATA 250
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
b0 4.3383 1.2543 572 3.46 0.0006 0.05 1.8747 6.8018 -2.31E-6
b1 -0.7549 0.5657 572 -1.33 0.1826 0.05 -1.8661 0.3562 -1.59E-6
b2 0.4583 0.4805 572 0.95 0.3405 0.05 -0.4853 1.4020 1.889E-6
b3 0.1511 0.4824 572 0.31 0.7543 0.05 -0.7964 1.0985 -3.57E-6
b4 -0.02017 0.5315 572 -0.04 0.9697 0.05 -1.0640 1.0237 -3.31E-6
b5 -0.3720 0.6063 572 -0.61 0.5398 0.05 -1.5629 0.8189 1.336E-6
b6 0.1531 0.1381 572 1.11 0.2680 0.05 -0.1181 0.4242 -0.00002
b7 -0.04538 0.04247 572 -1.07 0.2858 0.05 -0.1288 0.03804 -0.00009
V1 2.1366 0.2189 572 9.76 <.0001 0.05 1.7066 2.5665 -4.03E-6
Additional Estimates
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
V1^2 4.5649 0.9354 572 4.88 <.0001 0.05 2.7276 6.4021
11. Laplace approximation:
Specifications
Data Set WORK.DAT
Dependent Variable bsat
Distribution for Dependent Variable Binary
Random Effects g1
Distribution for Random Effects Normal
Subject Variable FAMNR
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 2102
Observations Not Used 1336
Total Observations 3438
Subjects 573
Max Obs Per Subject 6
Parameters 9
Quadrature Points 1
Parameters
b0 b1 b2 b3 b4 b5 b6 b7 V1 NegLogLike
2.8528 -0.5465 0.3001 0.1213 -0.02867 -0.2656 0.06617 -0.03079 2.3662 657.172467
Iteration History
DATASET 6. MARITAL SATISFACTION DATA 251
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 595.845906 61.32656 68.97154 -26737.2
2 5 592.559211 3.286695 4.377269 -5.83548
3 7 591.491572 1.067638 85.99581 -0.61735
4 9 589.77634 1.715232 10.01569 -0.98064
5 11 589.038678 0.737662 10.38077 -0.3982
6 13 588.806169 0.232509 7.468499 -0.1661
7 15 588.305644 0.500526 12.86172 -0.14436
8 17 588.09221 0.213434 2.394789 -0.15723
9 19 588.001329 0.090881 2.080519 -0.08249
10 21 587.949209 0.052119 5.456902 -0.02362
11 23 587.783881 0.165328 15.11569 -0.04455
12 25 587.700576 0.083305 10.9808 -0.0695
13 27 587.654848 0.045728 13.06041 -0.02491
14 29 587.487859 0.166989 12.27121 -0.03259
15 30 587.297756 0.190103 8.331522 -0.13393
16 32 587.2794 0.018356 0.325252 -0.03008
17 34 587.271866 0.007534 4.250006 -0.00337
18 36 587.160245 0.111622 4.205993 -0.01103
19 38 587.116511 0.043733 0.250661 -0.06816
20 40 587.115935 0.000576 0.017436 -0.00105
21 42 587.115934 1.021E-6 0.002356 -2E-6
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 1174.2
AIC (smaller is better) 1192.2
AICC (smaller is better) 1192.3
BIC (smaller is better) 1231.4
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
b0 6.0577 1.7343 572 3.49 0.0005 0.05 2.6514 9.4641 0.000116
b1 -0.7566 0.6993 572 -1.08 0.2798 0.05 -2.1302 0.6170 0.00005
b2 0.6263 0.5567 572 1.13 0.2610 0.05 -0.4671 1.7197 0.000159
b3 0.1576 0.5220 572 0.30 0.7628 0.05 -0.8676 1.1829 0.000195
b4 -0.01072 0.5792 572 -0.02 0.9852 0.05 -1.1483 1.1269 0.000082
b5 -0.4580 0.6614 572 -0.69 0.4889 0.05 -1.7572 0.8412 0.000107
b6 0.2188 0.1843 572 1.19 0.2356 0.05 -0.1432 0.5809 0.000238
b7 -0.04728 0.05652 572 -0.84 0.4033 0.05 -0.1583 0.06375 0.002356
V1 4.0665 0.8547 572 4.76 <.0001 0.05 2.3878 5.7452 -0.00011
Additional Estimates
DATASET 6. MARITAL SATISFACTION DATA 252
Standard
Label Estimate Error DF t Value Pr > |t| Alpha Lower Upper
V1^2 16.5364 6.9512 572 2.38 0.0177 0.05 2.8834 30.1894
12. Fitted marginal evolutions and evolutions for the median parent:
Figure 6.1: Fitted marginal average evolution per parent
Figure 6.2: Fitted evolutions for the median parent
13. Test for the parent effect:
Specifications
DATASET 6. MARITAL SATISFACTION DATA 253
Data Set WORK.DAT
Dependent Variable bsat
Distribution for Dependent Variable Binary
Random Effects g1
Distribution for Random Effects Normal
Subject Variable FAMNR
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 2102
Observations Not Used 1336
Total Observations 3438
Subjects 573
Max Obs Per Subject 6
Parameters 6
Quadrature Points 20
Parameters
b0 b1 b2 b3 b4 V1 NegLogLike
2.8528 -0.5465 0.3001 0.1213 -0.02867 2.3662 644.510467
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 606.325514 38.18495 45.12185 -15955.8
2 5 603.822625 2.502889 33.51163 -3.92549
3 6 603.329753 0.492872 9.345013 -0.73621
4 8 602.834818 0.494935 17.2674 -0.46348
5 10 602.54832 0.286498 1.79628 -0.31385
6 12 602.497864 0.050457 6.899228 -0.02872
7 13 602.416047 0.081816 1.318331 -0.05246
8 15 602.394229 0.021818 3.097594 -0.02785
9 17 602.254877 0.139352 2.300388 -0.01376
10 18 602.090257 0.16462 2.49476 -0.08792
11 19 601.936675 0.153583 5.918115 -0.12149
12 21 601.923015 0.013659 0.745047 -0.02845
13 23 601.922945 0.000071 0.036981 -0.00014
14 25 601.922944 2.162E-7 0.005385 -4.5E-7
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
DATASET 6. MARITAL SATISFACTION DATA 254
-2 Log Likelihood 1203.8
AIC (smaller is better) 1215.8
AICC (smaller is better) 1215.9
BIC (smaller is better) 1242.0
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
b0 4.4049 1.2345 572 3.57 0.0004 0.05 1.9802 6.8295 -0.00023
b1 -0.7615 0.5108 572 -1.49 0.1366 0.05 -1.7648 0.2419 -0.00014
b2 0.2789 0.3846 572 0.73 0.4686 0.05 -0.4765 1.0343 -0.00009
b3 0.1534 0.1380 572 1.11 0.2666 0.05 -0.1175 0.4244 -0.00036
b4 -0.04539 0.04242 572 -1.07 0.2852 0.05 -0.1287 0.03794 -0.00538
V1 2.1334 0.2185 572 9.76 <.0001 0.05 1.7041 2.5626 0.000179
Obs logL0 logL1 LRT df pval
1 -601.9 -601.5 0.8 3 0.84947
Part 4
1. Missing Data Patterns
Missing Data Patterns
Group sat1 sat2 sat3 Freq Percent
1 X X X 268 23.39
2 X X . 392 34.21
3 X . X 41 3.58
4 X . . 428 37.35
5 . X X 1 0.09
6 . X . 2 0.17
7 O O O 14 1.22
2. Continuous Response: Procedure MIXED: CC
Model Information
Data Set WORK.MSDCC
Dependent Variable SAT
Covariance Structure Unstructured @ Compound
Symmetry
Subject Effect FAMNR
Estimation Method ML
Residual Variance Method None
Fixed Effects SE Method Model-Based
Degrees of Freedom Method Between-Within
Class Level Information
Class Levels Values
FAMNR 122 95 96 116 129 281 299 324 ...
IDNR 244 23 24 25 26 39 40 47 48 77 ...
YEAR 3 1990 1995 2000
DATASET 6. MARITAL SATISFACTION DATA 255
STATUS 2 1 2
PARENT 2 0 1
Dimensions
Covariance Parameters 4
Columns in X 11
Columns in Z 0
Subjects 122
Max Obs Per Subject 6
Number of Observations
Number of Observations Read 732
Number of Observations Used 732
Number of Observations Not Used 0
Iteration History
Iteration Evaluations -2 Log Like Criterion
0 1 1920.18682894
1 2 1650.94511948 0.00935836
2 1 1649.41391865 0.00014849
3 1 1649.39099699 0.00000009
4 1 1649.39098381 0.00000000
Convergence criteria met.
Estimated R Matrix for FAMNR 95
Row Col1 Col2 Col3 Col4 Col5 Col6
1 0.7011 0.2696 0.3620 0.1392 0.3620 0.1392
2 0.2696 0.8309 0.1392 0.4290 0.1392 0.4290
3 0.3620 0.1392 0.7011 0.2696 0.3620 0.1392
4 0.1392 0.4290 0.2696 0.8309 0.1392 0.4290
5 0.3620 0.1392 0.3620 0.1392 0.7011 0.2696
6 0.1392 0.4290 0.1392 0.4290 0.2696 0.8309
Estimated R Correlation Matrix for FAMNR 95
Row Col1 Col2 Col3 Col4 Col5 Col6
1 1.0000 0.3532 0.5164 0.1824 0.5164 0.1824
2 0.3532 1.0000 0.1824 0.5164 0.1824 0.5164
3 0.5164 0.1824 1.0000 0.3532 0.5164 0.1824
4 0.1824 0.5164 0.3532 1.0000 0.1824 0.5164
5 0.5164 0.1824 0.5164 0.1824 1.0000 0.3532
6 0.1824 0.5164 0.1824 0.5164 0.3532 1.0000
Covariance Parameter Estimates
Cov Parm Subject Estimate
PARENT UN(1,1) FAMNR 0.7011
UN(2,1) FAMNR 0.2696
UN(2,2) FAMNR 0.8309
YEAR Corr FAMNR 0.5164
Fit Statistics
-2 Log Likelihood 1649.4
AIC (smaller is better) 1667.4
AICC (smaller is better) 1667.6
BIC (smaller is better) 1692.6
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
3 270.80 <.0001
DATASET 6. MARITAL SATISFACTION DATA 256
Solution for Fixed Effects
Standard
Effect YEAR PARENT Estimate Error DF t Value Pr > |t|
YEAR 1990 5.2588 0.08253 242 63.72 <.0001
YEAR 1995 5.9184 0.08253 242 71.72 <.0001
YEAR 2000 5.7037 0.08253 242 69.11 <.0001
PARENT 0 0.04313 0.09021 121 0.48 0.6334
PARENT 1 0 . . . .
YEAR*PARENT 1990 0 -0.07533 0.08872 242 -0.85 0.3967
YEAR*PARENT 1990 1 0 . . . .
YEAR*PARENT 1995 0 0.06206 0.08872 242 0.70 0.4849
YEAR*PARENT 1995 1 0 . . . .
YEAR*PARENT 2000 0 0 . . . .
YEAR*PARENT 2000 1 0 . . . .
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 2 242 66.89 <.0001
PARENT 1 121 0.27 0.6031
YEAR*PARENT 2 242 1.20 0.3021
3. Continuous Response: Procedure MIXED: Direct Likelihood
Model Information
Data Set WORK.MSDIC
Dependent Variable SAT
Covariance Structure Unstructured @ Compound
Symmetry
Subject Effect FAMNR
Estimation Method ML
Residual Variance Method None
Fixed Effects SE Method Model-Based
Degrees of Freedom Method Between-Within
Class Level Information
Class Levels Values
FAMNR 573 15 47 54 60 62 64 72 90 91 ...
IDNR 1146 1 2 3 4 5 6 7 8 9 10 11 12 ...
YEAR 3 1990 1995 2000
STATUS 2 1 2
PARENT 2 0 1
Dimensions
Covariance Parameters 4
Columns in X 11
Columns in Z 0
Subjects 573
Max Obs Per Subject 6
Number of Observations
Number of Observations Read 3438
Number of Observations Used 2102
Number of Observations Not Used 1336
Iteration History
Iteration Evaluations -2 Log Like Criterion
0 1 5748.17979945
1 2 5127.95955233 0.00038577
DATASET 6. MARITAL SATISFACTION DATA 257
2 1 5127.71116168 0.00000032
3 1 5127.71095688 0.00000000
Convergence criteria met.
Estimated R Matrix
for FAMNR 15
Row Col1 Col2
1 0.8061 0.3822
2 0.3822 0.9431
Estimated R Correlation
Matrix for FAMNR 15
Row Col1 Col2
1 1.0000 0.4383
2 0.4383 1.0000
Covariance Parameter Estimates
Cov Parm Subject Estimate
PARENT UN(1,1) FAMNR 0.8061
UN(2,1) FAMNR 0.3822
UN(2,2) FAMNR 0.9431
YEAR Corr FAMNR 0.5178
Fit Statistics
-2 Log Likelihood 5127.7
AIC (smaller is better) 5145.7
AICC (smaller is better) 5145.8
BIC (smaller is better) 5184.9
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
3 620.47 <.0001
Solution for Fixed Effects
Standard
Effect YEAR PARENT Estimate Error DF t Value Pr > |t|
YEAR 1990 5.1867 0.04071 511 127.42 <.0001
YEAR 1995 5.9319 0.04945 511 119.96 <.0001
YEAR 2000 5.6027 0.06653 511 84.21 <.0001
PARENT 0 0.06192 0.07052 558 0.88 0.3803
PARENT 1 0 . . . .
YEAR*PARENT 1990 0 -0.06323 0.07013 455 -0.90 0.3677
YEAR*PARENT 1990 1 0 . . . .
YEAR*PARENT 1995 0 -0.01516 0.07339 455 -0.21 0.8365
YEAR*PARENT 1995 1 0 . . . .
YEAR*PARENT 2000 0 0 . . . .
YEAR*PARENT 2000 1 0 . . . .
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
YEAR 2 511 186.80 <.0001
PARENT 1 558 0.76 0.3852
YEAR*PARENT 2 455 0.65 0.5206
4. Continuous Response: Procedure MIXED: Multiple Imputation
------------------------------------- Imputation Number=1 --------------------------------------
DATASET 6. MARITAL SATISFACTION DATA 258
Model Information
Data Set WORK.MSDICCOMP
Dependent Variable SAT
Covariance Structure Unstructured @ Compound
Symmetry
Subject Effect FAMNR
Estimation Method ML
Residual Variance Method None
Fixed Effects SE Method Model-Based
Degrees of Freedom Method Between-Within
Class Level Information
Class Levels Values
FAMNR 573 15 47 54 60 62 64 72 90 91 ...
YEAR 3 1990 1995 2000
PARENT 2 0 1
Dimensions
Covariance Parameters 7
Columns in X 6
Columns in Z 0
Subjects 573
Max Obs Per Subject 6
Number of Observations
Number of Observations Read 3438
Number of Observations Used 3438
Number of Observations Not Used 0
Iteration History
Iteration Evaluations -2 Log Like Criterion
0 1 9683.98628048
1 2 9360.46272795 0.00004508
2 1 9360.39341474 0.00000001
3 1 9360.39339499 0.00000000
Convergence criteria met.
Estimated R Correlation Matrix for FAMNR 15
Row Col1 Col2 Col3 Col4 Col5 Col6
1 1.0000 0.2731 0.2906 0.07937 0.1150 0.03140
2 0.2731 1.0000 0.07937 0.2906 0.03140 0.1150
3 0.2906 0.07937 1.0000 0.2731 0.1045 0.02853
4 0.07937 0.2906 0.2731 1.0000 0.02853 0.1045
5 0.1150 0.03140 0.1045 0.02853 1.0000 0.2731
6 0.03140 0.1150 0.02853 0.1045 0.2731 1.0000
Covariance Parameter Estimates
Standard Z
Cov Parm Subject Estimate Error Value Pr Z
YEAR UN(1,1) FAMNR 0.7375 0.03084 23.92 <.0001
UN(2,1) FAMNR 0.2621 0.02780 9.43 <.0001
UN(2,2) FAMNR 1.1031 0.04650 23.72 <.0001
UN(3,1) FAMNR 0.1030 0.02663 3.87 0.0001
UN(3,2) FAMNR 0.1144 0.03255 3.52 0.0004
UN(3,3) FAMNR 1.0876 0.04681 23.24 <.0001
PARENT Corr FAMNR 0.2731 0.02268 12.04 <.0001
Asymptotic Covariance Matrix of Estimates
DATASET 6. MARITAL SATISFACTION DATA 259
Row Cov Parm CovP1 CovP2 CovP3 CovP4 CovP5 CovP6 CovP7
1 YEAR UN(1,1) 0.000951 0.000335 0.000128 0.000132 0.000046 0.000033 0.000030
2 UN(2,1) 0.000335 0.000773 0.000494 0.000098 0.000127 1.964E-6 -0.00004
3 UN(2,2) 0.000128 0.000494 0.002162 0.000050 0.000214 0.000093 0.000141
4 UN(3,1) 0.000132 0.000098 0.000050 0.000709 0.000260 0.000191 -9.98E-6
5 UN(3,2) 0.000046 0.000127 0.000214 0.000260 0.001059 0.000206 -0.00002
6 UN(3,3) 0.000033 1.964E-6 0.000093 0.000191 0.000206 0.002191 0.000255
7 PARENT Corr 0.000030 -0.00004 0.000141 -9.98E-6 -0.00002 0.000255 0.000514
Fit Statistics
-2 Log Likelihood 9360.4
AIC (smaller is better) 9386.4
AICC (smaller is better) 9386.5
BIC (smaller is better) 9443.0
Null Model Likelihood Ratio Test
DF Chi-Square Pr > ChiSq
6 323.59 <.0001
Solution for Fixed Effects
Standard
Effect Estimate Error DF t Value Pr > |t|
year1990 5.1915 0.03588 2859 144.70 <.0001
year1995 5.7965 0.04388 2859 132.11 <.0001
year2000 5.9290 0.04357 2859 136.09 <.0001
father -0.03170 0.05253 2859 -0.60 0.5462
father1990 0.02522 0.06410 2859 0.39 0.6940
father1995 0.1374 0.07055 2859 1.95 0.0516
Covariance Matrix for Fixed Effects
Row Effect Col1 Col2 Col3 Col4 Col5 Col6
1 year1990 0.001287 0.000457 0.000180 -0.00013 -0.00080 -0.00020
2 year1995 0.000457 0.001925 0.000200 -0.00015 -0.00019 -0.00125
3 year2000 0.000180 0.000200 0.001898 -0.00138 0.001249 0.001235
4 father -0.00013 -0.00015 -0.00138 0.002760 -0.00250 -0.00247
5 father1990 -0.00080 -0.00019 0.001249 -0.00250 0.004108 0.002873
6 father1995 -0.00020 -0.00125 0.001235 -0.00247 0.002873 0.004978
Type 3 Tests of Fixed Effects
Num Den
Effect DF DF F Value Pr > F
year1990 1 2859 20939.5 <.0001
year1995 1 2859 17452.9 <.0001
year2000 1 2859 18520.0 <.0001
father 1 2859 0.36 0.5462
father1990 1 2859 0.15 0.6940
father1995 1 2859 3.79 0.0516
...
COMBINING 5 MIXED MODEL ANALYSES: The MIANALYZE Procedure
Model Information
PARMS Data Set WORK.SOLUTION0
COVB Data Set WORK.COVB0
Number of Imputations 5
Multiple Imputation Variance Information
-----------------Variance-----------------
DATASET 6. MARITAL SATISFACTION DATA 260
Parameter Between Within Total DF
year1990 0.000016438 0.001298 0.001318 17846
year1995 0.000899 0.001851 0.002930 29.48
year2000 0.001198 0.001805 0.003242 20.352
father 0.004480 0.002638 0.008014 8.8887
father1990 0.003539 0.003991 0.008238 15.052
father1995 0.005888 0.004726 0.011792 11.142
Multiple Imputation Variance Information
Relative Fraction
Increase Missing Relative
Parameter in Variance Information Efficiency
year1990 0.015199 0.015082 0.996993
year1995 0.583167 0.407249 0.924685
year2000 0.796381 0.491001 0.910581
father 2.037909 0.726202 0.873179
father1990 1.064006 0.569183 0.897798
father1995 1.494889 0.655867 0.884038
Multiple Imputation Parameter Estimates
Parameter Estimate Std Error 95% Confidence Limits DF
year1990 5.188727 0.036298 5.11758 5.259875 17846
year1995 5.820415 0.054129 5.70979 5.931044 29.48
year2000 5.899974 0.056936 5.78134 6.018608 20.352
father 0.037407 0.089520 -0.16549 0.240302 8.8887
father1990 -0.033850 0.090766 -0.22725 0.159554 15.052
father1995 0.014804 0.108590 -0.22383 0.253440 11.142
year1990 5.11758 5.259875 17846
year1995 5.70979 5.931044 29.48
year2000 5.78134 6.018608 20.352
father -0.16549 0.240302 8.8887
father1990 -0.22725 0.159554 15.052
father1995 -0.22383 0.253440 11.142
Multiple Imputation Parameter Estimates
t for H0:
Parameter Minimum Maximum Theta0 Parameter=Theta0 Pr > |t|
year1990 5.182633 5.193179 0 142.95 <.0001
year1995 5.796500 5.863764 0 107.53 <.0001
year2000 5.847270 5.933238 0 103.63 <.0001
father -0.031703 0.110921 0 0.42 0.6860
father1990 -0.096769 0.025219 0 -0.37 0.7144
father1995 -0.059910 0.137388 0 0.14 0.8940
Model Information
PARMS Data Set WORK.COVPARMS0
COVB Data Set WORK.ASYCOV0
Number of Imputations 5
Multiple Imputation Variance Information
-----------------Variance-----------------
Parameter Between Within Total DF
YEARUN11 0.000062945 0.000966 0.001042 761.21
YEARUN21 0.000138 0.000754 0.000920 123.71
YEARUN22 0.002220 0.002002 0.004666 12.276
YEARUN31 0.000107 0.000681 0.000810 158.78
YEARUN32 0.000197 0.000971 0.001207 104.61
YEARUN33 0.002091 0.001978 0.004487 12.797
DATASET 6. MARITAL SATISFACTION DATA 261
PARENTCO 0.000148 0.000519 0.000697 61.598
Multiple Imputation Variance Information
Relative Fraction
Increase Missing Relative
Parameter in Variance Information Efficiency
YEARUN11 0.078155 0.074917 0.985238
YEARUN21 0.219243 0.192765 0.962878
YEARUN22 1.330063 0.627017 0.888570
YEARUN31 0.188663 0.169119 0.967283
YEARUN32 0.243076 0.210496 0.959602
YEARUN33 1.268001 0.614906 0.890487
PARENTCO 0.341971 0.277898 0.947347
Multiple Imputation Parameter Estimates
Parameter Estimate Std Error 95% Confidence Limits DF
YEARUN11 0.743651 0.032280 0.680282 0.807019 761.21
YEARUN21 0.266324 0.030328 0.206296 0.326353 123.71
YEARUN22 1.060462 0.068308 0.912003 1.208921 12.276
YEARUN31 0.106555 0.028458 0.050349 0.162760 158.78
YEARUN32 0.121139 0.034740 0.052252 0.190025 104.61
YEARUN33 1.034015 0.066986 0.889066 1.178965 12.797
PARENTCO 0.269105 0.026393 0.216340 0.321870 61.598
Multiple Imputation Parameter Estimates
t for H0:
Parameter Minimum Maximum Theta0 Parameter=Theta0 Pr > |t|
YEARUN11 0.736704 0.755575 0 23.04 <.0001
YEARUN21 0.258364 0.287125 0 8.78 <.0001
YEARUN22 1.016246 1.117173 0 15.52 <.0001
YEARUN31 0.091112 0.118612 0 3.74 0.0003
YEARUN32 0.108231 0.144682 0 3.49 0.0007
YEARUN33 0.973560 1.087629 0 15.44 <.0001
PARENTCO 0.254140 0.280608 0 10.20 <.0001
5. Binary Response: Procedure GEE: CC
Model Information
Data Set WORK.MSDCC
Distribution Binomial
Link Function Logit
Dependent Variable BSAT BSAT
Number of Observations Read 732
Number of Observations Used 732
Number of Events 679
Number of Trials 732
Class Level Information
Class Levels Values
FAMNR 122 95 96 116 ...
YEAR 3 1990 1995 2000
PARENT 2 0 1
Response Profile
Ordered Total
Value BSAT Frequency
1 1 679
2 0 53
DATASET 6. MARITAL SATISFACTION DATA 262
PROC GENMOD is modeling the probability that BSAT=’1’.
Parameter Information
Parameter Effect YEAR PARENT
Prm1 Intercept
Prm2 PARENT 0
Prm3 PARENT 1
Prm4 YEAR 1990
Prm5 YEAR 1995
Prm6 YEAR 2000
Prm7 BIRTH
Prm8 YEAR*PARENT 1990 0
Prm9 YEAR*PARENT 1990 1
Prm10 YEAR*PARENT 1995 0
Prm11 YEAR*PARENT 1995 1
Prm12 YEAR*PARENT 2000 0
Prm13 YEAR*PARENT 2000 1
Prm14 BIRTH*PARENT 0
Prm15 BIRTH*PARENT 1
Prm16 BIRTH*YEAR 1990
Prm17 BIRTH*YEAR 1995
Prm18 BIRTH*YEAR 2000
Prm19 BIRTH*YEAR*PARENT 1990 0
Prm20 BIRTH*YEAR*PARENT 1990 1
Prm21 BIRTH*YEAR*PARENT 1995 0
Prm22 BIRTH*YEAR*PARENT 1995 1
Prm23 BIRTH*YEAR*PARENT 2000 0
Prm24 BIRTH*YEAR*PARENT 2000 1
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 720 372.2591 0.5170
Scaled Deviance 720 372.2591 0.5170
Pearson Chi-Square 720 717.8982 0.9971
Scaled Pearson X2 720 717.8982 0.9971
Log Likelihood -186.1295
Algorithm converged.
Analysis Of Initial Parameter Estimates
Standard Wald 95% Chi-
Parameter DF Estimate Error Confidence Limits Square Pr > ChiSq
Intercept 1 -3.7378 4.5822 -12.7188 5.2432 0.67 0.4147
PARENT 0 1 8.5801 5.8816 -2.9475 20.1078 2.13 0.1446
PARENT 1 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR 1990 1 9.4072 6.0691 -2.4881 21.3025 2.40 0.1211
YEAR 1995 1 10.8278 7.1164 -3.1201 24.7756 2.32 0.1281
YEAR 2000 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH 1 0.1305 0.0948 -0.0552 0.3163 1.90 0.1684
YEAR*PARENT 1990 0 1 -10.8144 7.9104 -26.3186 4.6897 1.87 0.1716
YEAR*PARENT 1990 1 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 1995 0 1 -14.8140 9.1629 -32.7728 3.1449 2.61 0.1059
YEAR*PARENT 1995 1 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 0 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 1 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*PARENT 0 1 -0.1814 0.1217 -0.4199 0.0571 2.22 0.1361
BIRTH*PARENT 1 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR 1990 1 -0.1993 0.1230 -0.4403 0.0417 2.63 0.1051
DATASET 6. MARITAL SATISFACTION DATA 263
BIRTH*YEAR 1995 1 -0.2125 0.1426 -0.4920 0.0671 2.22 0.1363
BIRTH*YEAR 2000 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1990 0 1 0.2265 0.1620 -0.0910 0.5440 1.95 0.1621
BIRTH*YEAR*PARENT 1990 1 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1995 0 1 0.3082 0.1876 -0.0595 0.6759 2.70 0.1004
BIRTH*YEAR*PARENT 1995 1 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 2000 0 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 2000 1 0 0.0000 0.0000 0.0000 0.0000 . .
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
GEE Model Information
Correlation Structure Unstructured
Within-Subject Effect YEAR(PARENT) (6 levels)
Subject Effect FAMNR (122 levels)
Number of Clusters 122
Correlation Matrix Dimension 6
Maximum Cluster Size 6
Minimum Cluster Size 6
Algorithm converged.
Working Correlation Matrix
Col1 Col2 Col3 Col4 Col5 Col6
Row1 1.0000 0.5610 0.4617 0.1900 0.2071 0.0649
Row2 0.5610 1.0000 0.7391 0.1685 0.3022 0.1989
Row3 0.4617 0.7391 1.0000 0.3001 0.2321 0.3163
Row4 0.1900 0.1685 0.3001 1.0000 0.3622 0.1770
Row5 0.2071 0.3022 0.2321 0.3622 1.0000 0.4760
Row6 0.0649 0.1989 0.3163 0.1770 0.4760 1.0000
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept -3.9428 3.4927 -10.7884 2.9029 -1.13 0.2590
PARENT 0 8.2868 3.6374 1.1576 15.4159 2.28 0.0227
PARENT 1 0.0000 0.0000 0.0000 0.0000 . .
YEAR 1990 10.5390 4.1980 2.3111 18.7668 2.51 0.0121
YEAR 1995 11.1059 4.9853 1.3349 20.8768 2.23 0.0259
YEAR 2000 0.0000 0.0000 0.0000 0.0000 . .
BIRTH 0.1347 0.0718 -0.0061 0.2755 1.88 0.0607
YEAR*PARENT 1990 0 -12.4878 4.7397 -21.7775 -3.1980 -2.63 0.0084
YEAR*PARENT 1990 1 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 1995 0 -17.3831 5.2857 -27.7428 -7.0234 -3.29 0.0010
YEAR*PARENT 1995 1 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*PARENT 0 -0.1750 0.0748 -0.3215 -0.0285 -2.34 0.0193
BIRTH*PARENT 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR 1990 -0.2219 0.0846 -0.3878 -0.0561 -2.62 0.0087
BIRTH*YEAR 1995 -0.2182 0.1001 -0.4144 -0.0219 -2.18 0.0293
BIRTH*YEAR 2000 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1990 0 0.2606 0.0967 0.0710 0.4502 2.69 0.0071
BIRTH*YEAR*PARENT 1990 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1995 0 0.3632 0.1119 0.1439 0.5824 3.25 0.0012
BIRTH*YEAR*PARENT 1995 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 2000 0 0.0000 0.0000 0.0000 0.0000 . .
DATASET 6. MARITAL SATISFACTION DATA 264
BIRTH*YEAR*PARENT 2000 1 0.0000 0.0000 0.0000 0.0000 . .
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept -3.9428 4.2124 -12.1989 4.3134 -0.94 0.3493
PARENT 0 8.2868 4.8847 -1.2871 17.8606 1.70 0.0898
PARENT 1 0.0000 0.0000 0.0000 0.0000 . .
YEAR 1990 10.5390 5.4407 -0.1247 21.2026 1.94 0.0527
YEAR 1995 11.1059 5.3650 0.5907 21.6211 2.07 0.0384
YEAR 2000 0.0000 0.0000 0.0000 0.0000 . .
BIRTH 0.1347 0.0874 -0.0365 0.3060 1.54 0.1231
YEAR*PARENT 1990 0 -12.4878 6.3517 -24.9369 -0.0386 -1.97 0.0493
YEAR*PARENT 1990 1 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 1995 0 -17.3831 5.8132 -28.7768 -5.9894 -2.99 0.0028
YEAR*PARENT 1995 1 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*PARENT 0 -0.1750 0.1011 -0.3732 0.0232 -1.73 0.0835
BIRTH*PARENT 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR 1990 -0.2219 0.1101 -0.4378 -0.0061 -2.02 0.0439
BIRTH*YEAR 1995 -0.2182 0.1073 -0.4286 -0.0078 -2.03 0.0421
BIRTH*YEAR 2000 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1990 0 0.2606 0.1294 0.0070 0.5142 2.01 0.0440
BIRTH*YEAR*PARENT 1990 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1995 0 0.3632 0.1185 0.1310 0.5953 3.07 0.0022
BIRTH*YEAR*PARENT 1995 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 2000 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 2000 1 0.0000 0.0000 0.0000 0.0000 . .
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
Score Statistics For Type 3 GEE Analysis
Chi-
Source DF Square Pr > ChiSq
PARENT 1 0.24 0.6242
YEAR 2 2.63 0.2685
BIRTH 1 0.01 0.9219
YEAR*PARENT 2 7.09 0.0289
BIRTH*PARENT 1 0.19 0.6596
BIRTH*YEAR 2 2.89 0.2355
BIRTH*YEAR*PARENT 2 7.63 0.0220
6. Binary Response: Procedure GEE: WGEE (Dropout Model)
Model Information
Data Set WORK.MSDICWGEE
Distribution Binomial
Link Function Logit
Dependent Variable DROPOUT
Number of Observations Read 3438
Number of Observations Used 1379
Number of Events 225
Number of Trials 1379
Missing Values 2059
Class Level Information
DATASET 6. MARITAL SATISFACTION DATA 265
Class Levels Values
FAMNR 569 15 47 54 ...
YEAR 2 1995 2000
STATUS 2 1 2
PREV 2 0 1
Response Profile
Ordered Total
Value DROPOUT Frequency
1 1 225
2 0 1154
PROC GENMOD is modeling the probability that DROPOUT=’1’.
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 1374 1034.2961 0.7528
Scaled Deviance 1374 1034.2961 0.7528
Pearson Chi-Square 1374 1298.8603 0.9453
Scaled Pearson X2 1374 1298.8603 0.9453
Log Likelihood -517.1480
Algorithm converged.
Analysis Of Parameter Estimates
Standard Wald 95% Confidence Chi-
Parameter DF Estimate Error Limits Square Pr > ChiSq
Intercept 1 -1.3186 0.7591 -2.8064 0.1691 3.02 0.0824
PREV 0 1 0.2316 0.2462 -0.2509 0.7142 0.89 0.3468
PREV 1 0 0.0000 0.0000 0.0000 0.0000 . .
PARENT 1 -4.3282 0.7140 -5.7276 -2.9287 36.75 <.0001
YEAR 1995 1 -0.3261 0.1570 -0.6339 -0.0183 4.31 0.0379
YEAR 2000 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH 1 0.0077 0.0158 -0.0232 0.0386 0.24 0.6252
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
7. Binary Response: Procedure GEE: WGEE(Analysis)
Model Information
Data Set WORK.MSDICWGEE2
Distribution Binomial
Link Function Logit
Dependent Variable BSAT BSAT
Scale Weight Variable WI
Number of Observations Read 3438
Number of Observations Used 1347
Sum of Weights 2730.865
Number of Events 1222
Number of Trials 1347
Missing Values 2091
Class Level Information
Class Levels Values
FAMNR 573 15 47 54 60 ...
YEAR 3 1990 1995 2000
PARENT 2 0 1
DATASET 6. MARITAL SATISFACTION DATA 266
Response Profile
Ordered Total
Value BSAT Frequency
1 1 2586.492
2 0 144.3727
PROC GENMOD is modeling the probability that BSAT=’1’.
Parameter Information
Parameter Effect YEAR PARENT
Prm1 Intercept
Prm2 PARENT 0
Prm3 PARENT 1
Prm4 YEAR 1990
Prm5 YEAR 1995
Parameter Information
Parameter Effect YEAR PARENT
Prm6 YEAR 2000
Prm7 BIRTH
Prm8 YEAR*PARENT 1990 0
Prm9 YEAR*PARENT 1990 1
Prm10 YEAR*PARENT 1995 0
Prm11 YEAR*PARENT 1995 1
Prm12 YEAR*PARENT 2000 0
Prm13 YEAR*PARENT 2000 1
Prm14 BIRTH*PARENT 0
Prm15 BIRTH*PARENT 1
Prm16 BIRTH*YEAR 1990
Prm17 BIRTH*YEAR 1995
Prm18 BIRTH*YEAR 2000
Prm19 BIRTH*YEAR*PARENT 1990 0
Prm20 BIRTH*YEAR*PARENT 1990 1
Prm21 BIRTH*YEAR*PARENT 1995 0
Prm22 BIRTH*YEAR*PARENT 1995 1
Prm23 BIRTH*YEAR*PARENT 2000 0
Prm24 BIRTH*YEAR*PARENT 2000 1
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 1335 1037.2206 0.7769
Scaled Deviance 1335 1037.2206 0.7769
Pearson Chi-Square 1335 2673.0973 2.0023
Scaled Pearson X2 1335 2673.0973 2.0023
Log Likelihood -518.6103
Algorithm converged.
Analysis Of Initial Parameter Estimates
Standard Wald 95% Chi-
Parameter DF Estimate Error Confidence Limits Square Pr > ChiSq
Intercept 1 -3.7376 3.6758 -10.9420 3.4668 1.03 0.3092
PARENT 0 1 16.5267 5.6271 5.4979 27.5556 8.63 0.0033
PARENT 1 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR 1990 1 1.8725 4.1690 -6.2986 10.0436 0.20 0.6533
YEAR 1995 1 10.8424 4.5339 1.9562 19.7287 5.72 0.0168
YEAR 2000 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH 1 0.1318 0.0763 -0.0177 0.2813 2.99 0.0840
DATASET 6. MARITAL SATISFACTION DATA 267
Analysis Of Initial Parameter Estimates
Standard Wald 95% Chi-
Parameter DF Estimate Error Confidence Limits Square Pr > ChiSq
YEAR*PARENT 1990 0 1 -13.5968 6.2095 -25.7673 -1.4264 4.79 0.0285
YEAR*PARENT 1990 1 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 1995 0 1 -19.1413 6.8943 -32.6539 -5.6286 7.71 0.0055
YEAR*PARENT 1995 1 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 0 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 1 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*PARENT 0 1 -0.3181 0.1170 -0.5475 -0.0887 7.38 0.0066
BIRTH*PARENT 1 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR 1990 1 -0.0590 0.0860 -0.2276 0.1096 0.47 0.4926
BIRTH*YEAR 1995 1 -0.2065 0.0925 -0.3879 -0.0252 4.98 0.0256
BIRTH*YEAR 2000 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1990 0 1 0.2675 0.1289 0.0148 0.5202 4.30 0.0380
BIRTH*YEAR*PARENT 1990 1 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1995 0 1 0.3549 0.1420 0.0767 0.6332 6.25 0.0124
BIRTH*YEAR*PARENT 1995 1 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 2000 0 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 2000 1 0 0.0000 0.0000 0.0000 0.0000 . .
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
GEE Model Information
Correlation Structure Unstructured
Within-Subject Effect YEAR(PARENT) (6 levels)
Subject Effect FAMNR (573 levels)
Number of Clusters 573
Clusters With Missing Values 508
Correlation Matrix Dimension 6
Maximum Cluster Size 6
Minimum Cluster Size 0
Algorithm converged.
Working Correlation Matrix
Col1 Col2 Col3 Col4 Col5 Col6
Row1 1.0000 0.1993 0.2405 0.1980 0.2368 0.1082
Row2 0.1993 1.0000 0.6525 0.2134 0.4173 0.4624
Row3 0.2405 0.6525 1.0000 0.2492 0.5165 0.4306
Row4 0.1980 0.2134 0.2492 1.0000 0.2289 0.1564
Row5 0.2368 0.4173 0.5165 0.2289 1.0000 0.4599
Row6 0.1082 0.4624 0.4306 0.1564 0.4599 1.0000
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept -3.0799 3.6293 -10.1931 4.0333 -0.85 0.3961
PARENT 0 14.0251 4.8978 4.4256 23.6245 2.86 0.0042
PARENT 1 0.0000 0.0000 0.0000 0.0000 . .
YEAR 1990 2.2806 3.9665 -5.4936 10.0547 0.57 0.5653
YEAR 1995 10.7817 4.8456 1.2844 20.2789 2.23 0.0261
YEAR 2000 0.0000 0.0000 0.0000 0.0000 . .
BIRTH 0.1257 0.0762 -0.0237 0.2750 1.65 0.0990
YEAR*PARENT 1990 0 -11.6462 5.1287 -21.6984 -1.5941 -2.27 0.0232
YEAR*PARENT 1990 1 0.0000 0.0000 0.0000 0.0000 . .
DATASET 6. MARITAL SATISFACTION DATA 268
YEAR*PARENT 1995 0 -14.3987 8.0971 -30.2686 1.4713 -1.78 0.0754
YEAR*PARENT 1995 1 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*PARENT 0 -0.2854 0.1003 -0.4819 -0.0889 -2.85 0.0044
BIRTH*PARENT 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR 1990 -0.0716 0.0824 -0.2332 0.0900 -0.87 0.3851
BIRTH*YEAR 1995 -0.2130 0.0983 -0.4056 -0.0203 -2.17 0.0303
BIRTH*YEAR 2000 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1990 0 0.2455 0.1056 0.0385 0.4524 2.32 0.0201
BIRTH*YEAR*PARENT 1990 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1995 0 0.2897 0.1598 -0.0236 0.6030 1.81 0.0699
BIRTH*YEAR*PARENT 1995 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 2000 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 2000 1 0.0000 0.0000 0.0000 0.0000 . .
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept -3.0799 3.6647 -10.2625 4.1027 -0.84 0.4007
PARENT 0 14.0251 4.3825 5.4356 22.6145 3.20 0.0014
PARENT 1 0.0000 0.0000 0.0000 0.0000 . .
YEAR 1990 2.2806 4.1313 -5.8166 10.3777 0.55 0.5809
YEAR 1995 10.7817 4.1139 2.7186 18.8447 2.62 0.0088
YEAR 2000 0.0000 0.0000 0.0000 0.0000 . .
BIRTH 0.1257 0.0762 -0.0237 0.2750 1.65 0.0990
YEAR*PARENT 1990 0 -11.6462 5.0433 -21.5309 -1.7616 -2.31 0.0209
YEAR*PARENT 1990 1 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 1995 0 -14.3987 5.7453 -25.6593 -3.1381 -2.51 0.0122
YEAR*PARENT 1995 1 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 0 0.0000 0.0000 0.0000 0.0000 . .
YEAR*PARENT 2000 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*PARENT 0 -0.2854 0.0911 -0.4639 -0.1069 -3.13 0.0017
BIRTH*PARENT 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR 1990 -0.0716 0.0852 -0.2387 0.0955 -0.84 0.4009
BIRTH*YEAR 1995 -0.2130 0.0843 -0.3782 -0.0477 -2.53 0.0115
BIRTH*YEAR 2000 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1990 0 0.2455 0.1044 0.0408 0.4501 2.35 0.0187
BIRTH*YEAR*PARENT 1990 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 1995 0 0.2897 0.1168 0.0608 0.5186 2.48 0.0131
BIRTH*YEAR*PARENT 1995 1 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 2000 0 0.0000 0.0000 0.0000 0.0000 . .
BIRTH*YEAR*PARENT 2000 1 0.0000 0.0000 0.0000 0.0000 . .
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
Score Statistics For Type 3 GEE Analysis
Chi-
Source DF Square Pr > ChiSq
PARENT 1 3.75 0.0528
YEAR 2 4.88 0.0871
BIRTH 1 0.38 0.5376
YEAR*PARENT 0 . .
BIRTH*PARENT 1 3.59 0.0580
BIRTH*YEAR 2 2.93 0.2308
BIRTH*YEAR*PARENT 2 3.71 0.1565
8. Binary Response: Procedure GEE: MULTIPLE IMPUTATION
DATASET 6. MARITAL SATISFACTION DATA 269
------------------------------------- Imputation Number=1 --------------------------------------
Model Information
Data Set WORK.MSDICCOMP
Distribution Binomial
Link Function Logit
Dependent Variable BSAT BSAT
Number of Observations Read 3438
Number of Observations Used 3438
Number of Events 3195
Number of Trials 3438
Class Level Information
Class Levels Values
FAMNR 573 15 47 54 60 ...
YEAR 3 1990 1995 2000
PARENT 2 0 1
Response Profile
Ordered Total
Value BSAT Frequency
1 1 3195
2 0 243
PROC GENMOD is modeling the probability that BSAT=’1’.
Parameter Information
Parameter Effect
Prm1 Intercept
Prm2 father
Prm3 year1990
Prm4 year1995
Prm5 BIRTH
Prm6 father1990
Prm7 father1995
Prm8 fatherbirth
Prm9 birth1990
Prm10 birth1995
Prm11 father1990birth
Prm12 father1995birth
Criteria For Assessing Goodness Of Fit
Criterion DF Value Value/DF
Deviance 3426 1681.1648 0.4907
Scaled Deviance 3426 1681.1648 0.4907
Pearson Chi-Square 3426 3430.9140 1.0014
Scaled Pearson X2 3426 3430.9140 1.0014
Log Likelihood -840.5824
Algorithm converged.
Estimated Covariance Matrix
Prm1 Prm2 Prm3 Prm4 Prm5 Prm6
Prm1 5.60685 -5.60685 -5.60685 -5.60685 -0.11298 5.60685
Prm2 -5.60685 11.77476 5.60685 5.60685 0.11298 -11.77476
Prm3 -5.60685 5.60685 7.85402 5.60685 0.11298 -7.85402
Prm4 -5.60685 5.60685 5.60685 10.84247 0.11298 -5.60685
Prm5 -0.11298 0.11298 0.11298 0.11298 0.002293 -0.11298
Prm6 5.60685 -11.77476 -7.85402 -5.60685 -0.11298 15.62355
DATASET 6. MARITAL SATISFACTION DATA 270
Prm7 5.60685 -11.77476 -5.60685 -10.84247 -0.11298 11.77476
Prm8 0.11298 -0.24114 -0.11298 -0.11298 -0.002293 0.24114
Prm9 0.11298 -0.11298 -0.15827 -0.11298 -0.002293 0.15827
Prm10 0.11298 -0.11298 -0.11298 -0.21666 -0.002293 0.11298
Prm11 -0.11298 0.24114 0.15827 0.11298 0.002293 -0.31988
Prm12 -0.11298 0.24114 0.11298 0.21666 0.002293 -0.24114
Estimated Covariance Matrix
Prm7 Prm8 Prm9 Prm10 Prm11 Prm12
Prm1 5.60685 0.11298 0.11298 0.11298 -0.11298 -0.11298
Prm2 -11.77476 -0.24114 -0.11298 -0.11298 0.24114 0.24114
Prm3 -5.60685 -0.11298 -0.15827 -0.11298 0.15827 0.11298
Prm4 -10.84247 -0.11298 -0.11298 -0.21666 0.11298 0.21666
Prm5 -0.11298 -0.002293 -0.002293 -0.002293 0.002293 0.002293
Prm6 11.77476 0.24114 0.15827 0.11298 -0.31988 -0.24114
Prm7 20.73424 0.24114 0.11298 0.21666 -0.24114 -0.42018
Prm8 0.24114 0.004984 0.002293 0.002293 -0.004984 -0.004984
Prm9 0.11298 0.002293 0.003212 0.002293 -0.003212 -0.002293
Prm10 0.21666 0.002293 0.002293 0.004360 -0.002293 -0.004360
Prm11 -0.24114 -0.004984 -0.003212 -0.002293 0.006610 0.004984
Prm12 -0.42018 -0.004984 -0.002293 -0.004360 0.004984 0.008589
Analysis Of Initial Parameter Estimates
Standard Wald 95% Confidence Chi-
Parameter DF Estimate Error Limits Square Pr > ChiSq
Intercept 1 0.7404 2.3679 -3.9005 5.3814 0.10 0.7545
father 1 2.8850 3.4314 -3.8405 9.6105 0.71 0.4005
year1990 1 -1.6792 2.8025 -7.1720 3.8136 0.36 0.5490
year1995 1 2.6716 3.2928 -3.7822 9.1253 0.66 0.4172
BIRTH 1 0.0465 0.0479 -0.0474 0.1403 0.94 0.3320
father1990 1 -0.4406 3.9527 -8.1877 7.3065 0.01 0.9112
father1995 1 -0.0413 4.5535 -8.9660 8.8834 0.00 0.9928
fatherbirth 1 -0.0480 0.0706 -0.1864 0.0903 0.46 0.4962
birth1990 1 0.0115 0.0567 -0.0995 0.1226 0.04 0.8385
birth1995 1 -0.0568 0.0660 -0.1862 0.0727 0.74 0.3900
father1990birth 1 0.0016 0.0813 -0.1577 0.1610 0.00 0.9840
father1995birth 1 -0.0139 0.0927 -0.1956 0.1677 0.02 0.8804
Scale 0 1.0000 0.0000 1.0000 1.0000
NOTE: The scale parameter was held fixed.
GEE Model Information
Correlation Structure Unstructured
Within-Subject Effect YEAR(PARENT) (6 levels)
Subject Effect FAMNR (573 levels)
Number of Clusters 573
Correlation Matrix Dimension 6
Maximum Cluster Size 6
Minimum Cluster Size 6
Algorithm converged.
Working Correlation Matrix
Col1 Col2 Col3 Col4 Col5 Col6
Row1 1.0000 0.2508 0.1414 0.3160 0.1403 0.0303
Row2 0.2508 1.0000 0.2823 0.1630 0.2344 0.1535
Row3 0.1414 0.2823 1.0000 0.1709 0.1551 0.2162
Row4 0.3160 0.1630 0.1709 1.0000 0.2242 0.0382
Row5 0.1403 0.2344 0.1551 0.2242 1.0000 0.1361
DATASET 6. MARITAL SATISFACTION DATA 271
Row6 0.0303 0.1535 0.2162 0.0382 0.1361 1.0000
Analysis Of GEE Parameter Estimates
Empirical Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.6317 1.9889 -3.2664 4.5298 0.32 0.7508
father 3.6371 2.6703 -1.5966 8.8708 1.36 0.1732
year1990 -1.2479 2.3786 -5.9098 3.4140 -0.52 0.5998
year1995 3.0881 2.5941 -1.9963 8.1725 1.19 0.2339
BIRTH 0.0487 0.0403 -0.0304 0.1277 1.21 0.2275
father1990 -1.2229 3.1118 -7.3218 4.8761 -0.39 0.6943
father1995 -0.4566 3.8246 -7.9526 7.0394 -0.12 0.9050
fatherbirth -0.0637 0.0544 -0.1704 0.0429 -1.17 0.2415
birth1990 0.0029 0.0482 -0.0917 0.0974 0.06 0.9528
birth1995 -0.0651 0.0524 -0.1679 0.0377 -1.24 0.2145
father1990birth 0.0177 0.0639 -0.1076 0.1430 0.28 0.7824
father1995birth -0.0053 0.0773 -0.1568 0.1461 -0.07 0.9448
Analysis Of GEE Parameter Estimates
Model-Based Standard Error Estimates
Standard 95% Confidence
Parameter Estimate Error Limits Z Pr > |Z|
Intercept 0.6317 2.3328 -3.9406 5.2040 0.27 0.7866
father 3.6371 3.1326 -2.5028 9.7769 1.16 0.2456
year1990 -1.2479 2.7294 -6.5975 4.1017 -0.46 0.6475
year1995 3.0881 3.0585 -2.9064 9.0826 1.01 0.3126
BIRTH 0.0487 0.0472 -0.0439 0.1412 1.03 0.3026
father1990 -1.2229 3.5778 -8.2353 5.7896 -0.34 0.7325
father1995 -0.4566 3.9644 -8.2267 7.3136 -0.12 0.9083
fatherbirth -0.0637 0.0643 -0.1897 0.0622 -0.99 0.3213
birth1990 0.0029 0.0552 -0.1054 0.1111 0.05 0.9588
birth1995 -0.0651 0.0613 -0.1853 0.0550 -1.06 0.2882
father1990birth 0.0177 0.0733 -0.1261 0.1614 0.24 0.8097
father1995birth -0.0053 0.0804 -0.1630 0.1523 -0.07 0.9470
Scale 1.0000 . . . . .
NOTE: The scale parameter was held fixed.
Score Statistics For Type 3 GEE Analysis
Chi-
Source DF Square Pr > ChiSq
father 1 1.56 0.2113
year1990 1 0.26 0.6134
year1995 1 1.22 0.2687
BIRTH 1 1.28 0.2587
father1990 1 0.14 0.7110
father1995 1 0.01 0.9123
fatherbirth 1 1.16 0.2810
birth1990 1 0.00 0.9546
birth1995 1 1.34 0.2475
father1990birth 1 0.07 0.7951
father1995birth 1 0.00 0.9491
...
COMBINING 5 GEE ANALYSES: The MIANALYZE Procedure
Model Information
DATASET 6. MARITAL SATISFACTION DATA 272
PARMS Data Set WORK.GMPARMS
PARMINFO Data Set WORK.GMPINFO
COVB Data Set WORK.GMCOVB
Number of Imputations 5
Multiple Imputation Variance Information
-----------------Variance-----------------
Parameter Between Within Total DF
intercept 1.788537 4.805738 6.951982 41.968
father 4.173570 8.063189 13.071473 27.248
year1990 1.699900 7.032767 9.072646 79.126
year1995 2.487329 8.335452 11.320247 57.536
BIRTH 0.000976 0.001992 0.003163 29.186
father1990 4.315186 11.839142 17.017365 43.2
father1995 2.981649 13.968385 17.546364 96.196
fatherbirth 0.001995 0.003403 0.005796 23.456
birth1990 0.001008 0.002903 0.004113 46.236
birth1995 0.001451 0.003389 0.005131 34.712
father1990birth 0.002074 0.004995 0.007483 36.169
father1995birth 0.001529 0.005805 0.007640 69.369
Multiple Imputation Variance Information
Relative Fraction
Increase Missing Relative
Parameter in Variance Information Efficiency
intercept 0.446600 0.339469 0.936423
father 0.621130 0.423933 0.921840
year1990 0.290054 0.243716 0.953522
year1995 0.358084 0.287996 0.945538
BIRTH 0.587815 0.409338 0.924328
father1990 0.437382 0.334408 0.937311
father1995 0.256148 0.219966 0.957861
fatherbirth 0.703448 0.457334 0.916198
birth1990 0.416694 0.322804 0.939354
birth1995 0.513919 0.374494 0.930320
father1990birth 0.498249 0.366634 0.931683
father1995birth 0.316017 0.261131 0.950366
Multiple Imputation Parameter Estimates
Parameter Estimate Std Error 95% Confidence Limits DF
intercept -0.338938 2.636661 -5.6601 4.98218 41.968
father 2.879104 3.615449 -4.5360 10.29424 27.248
year1990 -0.639482 3.012083 -6.6347 5.35577 79.126
year1995 2.791960 3.364557 -3.9441 9.52801 57.536
BIRTH 0.059730 0.056242 -0.0553 0.17473 29.186
father1990 -0.287554 4.125211 -8.6057 8.03061 43.2
father1995 -1.685472 4.188838 -10.0000 6.62909 96.196
fatherbirth -0.059170 0.076132 -0.2165 0.09815 23.456
birth1990 -0.001177 0.064135 -0.1303 0.12790 46.236
birth1995 -0.062871 0.071631 -0.2083 0.08259 34.712
father1990birth 0.008734 0.086507 -0.1667 0.18415 36.169
DATASET 6. MARITAL SATISFACTION DATA 273
father1995birth 0.032184 0.087407 -0.1422 0.20654 69.369
Multiple Imputation Parameter Estimates
t for H0:
Parameter Minimum Maximum Theta0 Parameter=Theta0 Pr > |t|
intercept -1.883722 1.128103 0 -0.13 0.8983
father 0.466879 5.716576 0 0.80 0.4327
year1990 -2.049814 0.944915 0 -0.21 0.8324
year1995 1.105505 4.815376 0 0.83 0.4101
BIRTH 0.033510 0.109385 0 1.06 0.2969
father1990 -3.200129 2.258947 0 -0.07 0.9447
father1995 -2.984348 0.744977 0 -0.40 0.6883
fatherbirth -0.121201 -0.008756 0 -0.78 0.4448
birth1990 -0.051380 0.023826 0 -0.02 0.9854
birth1995 -0.109385 -0.017590 0 -0.88 0.3861
father1990birth -0.045218 0.072547 0 0.10 0.9201
father1995birth -0.017459 0.061564 0 0.37 0.7138
9. Binary Response: Procedure NLMIXED: CC (LOGISTIC Start Par)
Analysis of Maximum Likelihood Estimates
Standard Wald
Parameter DF Estimate Error Chi-Square Pr > ChiSq
Intercept 1 -3.0258 1.7634 2.9445 0.0862
PARENT 0 1 -0.0187 1.7634 0.0001 0.9915
YEAR 1990 1 -1.5265 2.3326 0.4283 0.5128
YEAR 1995 1 -0.9470 2.6876 0.1242 0.7246
BIRTH 1 0.00830 0.0360 0.0532 0.8176
YEAR*PARENT 1990 0 1 1.1360 2.3326 0.2372 0.6263
YEAR*PARENT 1995 0 1 3.1353 2.6876 1.3609 0.2434
BIRTH*PARENT 0 1 0.00158 0.0360 0.0019 0.9651
BIRTH*YEAR 1990 1 0.0379 0.0474 0.6391 0.4240
BIRTH*YEAR 1995 1 0.0102 0.0547 0.0350 0.8516
BIRTH*YEAR*PARENT 1990 0 1 -0.0241 0.0474 0.2590 0.6108
BIRTH*YEAR*PARENT 1995 0 1 -0.0650 0.0547 1.4103 0.2350
10. Binary Response: Procedure NLMIXED: CC
Specifications
Data Set WORK.MSDCC
Dependent Variable BSAT
Distribution for Dependent Variable Binary
Random Effects g1
Distribution for Random Effects Normal
Subject Variable FAMNR
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 732
Observations Not Used 0
Total Observations 732
Subjects 122
Max Obs Per Subject 6
Parameters 13
DATASET 6. MARITAL SATISFACTION DATA 274
Quadrature Points 10
Parameters
b0 b1 b2 b3 b4 b5 b6 b7 b8
-3 -1.5 -0.9 0.1 0.008 1.1 3.1 0.002 0.04
Parameters
b9 b10 b11 V1 NegLogLike
0.01 -0.02 -0.065 2.3662 467.173863
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 4 251.192538 215.9813 2160.479 -329682
2 5 186.808564 64.38397 727.3123 -99.2999
3 6 173.65153 13.15703 218.1587 -20.2009
...
29 54 162.032463 0.000014 0.176163 -1.23E-6
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 324.1
AIC (smaller is better) 350.1
AICC (smaller is better) 350.6
BIC (smaller is better) 386.5
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
b0 1.7898 6.8875 121 0.26 0.7954 0.05 -11.8458 15.4255 -0.04705
b1 1.9448 8.1297 121 0.24 0.8113 0.05 -14.1501 18.0398 -0.07148
b2 -0.06616 9.3099 121 -0.01 0.9943 0.05 -18.4976 18.3653 -0.03293
b3 3.1077 7.9848 121 0.39 0.6978 0.05 -12.7004 18.9158 0.127968
b4 0.05051 0.1388 121 0.36 0.7165 0.05 -0.2243 0.3253 0.060808
b5 2.5654 10.4361 121 0.25 0.8062 0.05 -18.0955 23.2263 0.143268
b6 2.7611 11.9853 121 0.23 0.8182 0.05 -20.9669 26.4891 0.16376
b7 -0.07193 0.1635 121 -0.44 0.6608 0.05 -0.3957 0.2518 0.112962
b8 -0.05337 0.1636 121 -0.33 0.7448 0.05 -0.3773 0.2705 0.169062
b9 0.007904 0.1880 121 0.04 0.9665 0.05 -0.3643 0.3801 -0.08336
b10 -0.04318 0.2131 121 -0.20 0.8397 0.05 -0.4650 0.3786 0.176163
b11 -0.04736 0.2456 121 -0.19 0.8474 0.05 -0.5336 0.4389 0.00573
V1 2.1570 0.3846 121 5.61 <.0001 0.05 1.3956 2.9183 -0.00899
11. Binary Response: Procedure NLMIXED: Direct Likelihood
Specifications
Data Set WORK.MSDIC
Dependent Variable BSAT
Distribution for Dependent Variable Binary
Random Effects g1
Distribution for Random Effects Normal
Subject Variable FAMNR
Optimization Technique Dual Quasi-Newton
Integration Method Adaptive Gaussian
Quadrature
Dimensions
Observations Used 2102
DATASET 6. MARITAL SATISFACTION DATA 275
Observations Not Used 1336
Total Observations 3438
Subjects 573
Max Obs Per Subject 6
Parameters 13
Quadrature Points 10
Parameters
b0 b1 b2 b3 b4 b5 b6 b7 b8
-3 -1.5 -0.9 0.1 0.008 1.1 3.1 0.002 0.04
Parameters
b9 b10 b11 V1 NegLogLike
0.01 -0.02 -0.065 2.3662 1620.89446
Iteration History
Iter Calls NegLogLike Diff MaxGrad Slope
1 5 765.515534 855.3789 2996.607 -5010959
2 6 647.589176 117.9264 1287.777 -166.939
3 7 632.241291 15.34789 860.1845 -44.1928
...
31 66 597.464496 2.254E-6 0.128487 -4.32E-6
NOTE: GCONV convergence criterion satisfied.
Fit Statistics
-2 Log Likelihood 1194.9
AIC (smaller is better) 1220.9
AICC (smaller is better) 1221.1
BIC (smaller is better) 1277.5
Parameter Estimates
Standard
Parameter Estimate Error DF t Value Pr > |t| Alpha Lower Upper Gradient
b0 0.8072 4.7726 572 0.17 0.8658 0.05 -8.5668 10.1811 -0.00608
b1 -1.6750 5.0301 572 -0.33 0.7393 0.05 -11.5548 8.2048 -0.07512
b2 3.2998 5.6827 572 0.58 0.5617 0.05 -7.8617 14.4613 -0.09102
b3 2.9449 6.2556 572 0.47 0.6380 0.05 -9.3418 15.2316 0.037353
b4 0.05506 0.09610 572 0.57 0.5669 0.05 -0.1337 0.2438 -0.03355
b5 0.9481 6.7158 572 0.14 0.8878 0.05 -12.2425 14.1386 0.034565
b6 5.3107 7.7034 572 0.69 0.4909 0.05 -9.8198 20.4412 0.128487
b7 -0.05733 0.1284 572 -0.45 0.6553 0.05 -0.3095 0.1948 -0.0321
b8 0.02616 0.1014 572 0.26 0.7965 0.05 -0.1730 0.2253 0.00277
b9 -0.05388 0.1142 572 -0.47 0.6373 0.05 -0.2782 0.1704 -0.03374
b10 -0.01817 0.1378 572 -0.13 0.8952 0.05 -0.2889 0.2526 -0.00886
b11 -0.1165 0.1568 572 -0.74 0.4579 0.05 -0.4245 0.1915 -0.024
V1 2.1285 0.2091 572 10.18 <.0001 0.05 1.7177 2.5392 0.001664
6.3.3 Discussion
Part 1
2. Full model with unstructured mean and covariance structure: Consider year and status as categoricalvariables (put them in the class statement), all other covariates can be considered continuous.
DATASET 6. MARITAL SATISFACTION DATA 276
3. Final model after reducing mean structure (for both datasets): Only year, indicating the time at whichthe interview was taken, seems to have a significant effect on the marital satisfaction, both for fathers andmothers, meaning that the marital satisfaction changes over time. Taking a look at the parameter estimates(Tables 6.1-6.2), we can conclude that marital satisfaction increased from 1990 to 1995, and decreased againbetween 1995 and 2000 (but less than the increase 1990-1995), both for father and mother.
Table 6.1: Parameter Estimates for the Final Model for Father
Par. MLE (s.e.)
Year 1990 5.2266 (0.06773)
Year 1995 6.0236 (0.08209)
Year 2000 5.7469 (0.08731)
Table 6.2: Parameter Estimates for the Final Model for Mother
Par. MLE (s.e.)
Year 1990 5.2588 (0.07476)
Year 1995 5.9184 (0.08878)
Year 2000 5.7037 (0.08520)
4. Reducing the covariance structure (for both datasets): The different covariance structures can be putin a nesting scheme (Figure 6.3). When reducing the covariance structure, it is only allowed to reduce toa structure which is connected with (nested in) the original covariance structure. A likelihood ratio testis used to choose the best covariance structure (degrees of freedom equal to the difference in number ofparameters). We performed this reduction both for father and mother. Results are presented in Tables 6.3-6.4. For father, the covariance structure can be reduced to the heterogeneous compound symmetry (CSH),assuming 4 parameters, namely σ2
1 = 0.5793, σ22 = 0.8066, σ2
3 = 0.9165 and ρ = 0.6067. For mother, weborderline choose the compound symmetry (CS) covariance structure with 2 parameters, σ2
1 = 0.4468 andσ2 = 0.3962.
Figure 6.3: Nesting Scheme of the Different Covariance Structures
UN
UN(2) ARH(1) CSH TOEPH
UN(1) AR(1) CS TOEP
SIMPLE
�����������
��
��
��
��
���
�
��
��
��
��
���
?
CCCCCCCCCCCW
JJ
JJJ
@@
@@
@@
@@
@@
@R
HHHHHHHHHHj�
?
SS
SS
SS
SS
SS
Sw
��
��
� ?
CCCCCCCCCCCW
!!!!!!!!!!!!!)
������������
?
����������������������9
��
��
��
��
��
�
?�Q
Qs
JJJ
JJ
��
��
��
�����������
DATASET 6. MARITAL SATISFACTION DATA 277
Table 6.3: Summary of Covariance Structure Reduction for Father
Model Covariance −2` Par Ref G2 df p-value
1 UN 799.2 6
2 UN(2) 845.3 5 1 46.1 1 < 0.0001
3 ARH(1) 812.1 4 1 12.9 2 0.0016
4 TOEPH 802.7 5 1 3.5 1 0.0614
5 CSH 804.4 4 1 5.2 2 0.0743
4 1.7 1 0.4270
6 CS 814.8 2 5 10.4 2 0.0055
Table 6.4: Summary of Covariance Structure Reduction for Mother
Model Covariance −2` Par Ref G2 df p-value
1 UN 872.0 6
2 UN(2) 902.2 5 1 30.2 1 < 0.0001
3 ARH(1) 880.1 4 1 8.1 2 0.0174
4 TOEPH 873.9 5 1 1.9 1 0.1680
5 CSH 876.3 4 1 4.3 2 0.1220
4 2.4 1 0.3012
6 CS 880.1 2 5 3.8 1 0.0512
7 SIMPLE 976.2 1 6 96.1 1 < 0.0001
5. Modelling longitudinal data of both parents simultaneously: As mean structure, only year, parentand their interaction are included into the model, since year is the only covariate that seemed to have asignificant effect on marital satisfaction, when analyzing father and mother separately. To allow this effectto differ between parents, parent and its interaction with year is also included into the model.When both parents are analyzed together, an extra clustering is present, namely not only three measurementsper person (father or mother), but also both parents in a family. Therefore, the 6 × 6 covariance structurewill now consist of 6 (= 3 × 2) variances and 15 covariances. They can be estimated, using for example afully unstructured covariance matrix. However, it is more natural to estimate the covariance separately forthe two clustering variables (a 2×2 matrix for parent, and a 3×3 matrix for year), and afterwards takingthe Kronecker product of both matrices, also resulting in a 6×6 covariance matrix. In this way, SAS allowsthree possibilities, UN@UN, UN@AR(1) and UN@CS. From Table 6.5, we can conclude that reducing thecovariance structure using these special structures with the Kronecker product, does not fit the data well.Therefore, we stick to the fully 6 × 6 unstructured (UN) covariance matrix. However, this can be reducedalong the edges of Figure 6.3 in a similar way as the data for father and mother separately.
Table 6.5: Summary of Covariance Structure Reduction
Model Covariance −2` Par Ref G2 df p-value
1 UN 1603.4 21
2 UN@UN 1633.8 8 1 30.4 13 0.0041
3 UN@AR(1) 1663.7 4 2 29.9 4 < 0.0001
4 UN@CS 1649.4 4 2 15.6 4 0.0036
DATASET 6. MARITAL SATISFACTION DATA 278
Part 2
1. Covariance structure: Different choices can be considered for the covariance structure, e.g., unstructured,exchangeable or independence. Recall that the parameter estimators are consistent even if the workingcorrelation matrix is incorrect. However, an appropriate choice can improve the efficiency of the estimators.In the LMM analysis, different complicated covariance structures in the form of Kronecker products wereconsidered for the joint analysis of the two clustering variables. Since the covariance structure is treatedas a nuisance parameter in the GEE analysis, as e.g. an unstructured 6 × 6 matrix for the within classcorrelation structure in the REPEATED statement.
2. Univariate vs bivariate: The univariate and bivariate analyses lead essentially to the same final modelfor males and females: for males a very simple model with only an intercept, for females slightly morecomplicated. Note that taking into account the correlation between members of the same family does havean impact on the size of the parameter estimates.
3. Method In this section only the completers were used. However GEE is not a likelihood method and thereforethis model is only valid under MCAR. Other models will have to be considered when this assumption isquestionable.
Part 3
1. Multilevel model formulation: The dataset considered here is a typical example of an hierarchical datastructure with nested classification factors. In particular, a random sample of families has been collected andmarital satisfaction has been recorded in 1990, 1995 and 2000 for both parents resulting in 6 measurementsper family. In this setting, the marital satisfaction is expected to differ from one parent to the other withineach family and from family to family. Thus, the “family” and the “parent” are considered to be nestedclassification factors. A random effects term is then associated with the “family” factor and one with the“parent” factor nested within the “family”. This implies that the probability of marital satisfaction variesfrom family to family and in the same family the probability of marital satisfaction varies from husband towife.
2. Nested random effects results: The solution obtained from fitting the nested random effects modelunder PQL and MQL seems questionable since both methods lead to a non-positive definite random effectscovariance matrix. This could be attributed to the dichotomous nature of the data and the small numberof repeated measurements. On the contrary the fit using the adaptive Gauss Hermite method is successful.The likelihood ratio test suggests that the two-level random effects structure is not statistically significant(p-value = 0.0578). However, caution in needed in using such a test since the null hypothesis lies on theboundary of the parameter space.
3. PQL, MQL under both REML and ML: PQL and MQL behave similarly in parameter estimates andstandard errors under either REML and ML (see Table 6.6). However, it is known that they behave poorly forbinary outcomes with relatively small number of repeated measurements, as is the case in this example with6 measurements per family. Observe also that either in PQL or MQL, ML gives slightly smaller estimatesfor the covariance parameters than REML. This is due to the fact that REML accounts for the variabilityin estimating the fixed-effects coefficients. Finally, the information criteria should be treated with cautionsince they do not refer to the real data but to pseudo data.
4. Gaussian quadrature vs Adaptive quadrature: The number of nodes chosen in the Gaussian and adaptiveGaussian quadrature rule can have a direct impact on the estimated parameters, as it can be seen in Tables6.7 and 6.8. The impact is greater in the simple Gaussian rule than in the adaptive, in which slight changesare observed in the parameter estimates for more than 5 nodes.
5. Approximation methods in GLMMs: Table 6.9 shows severe differences in parameter estimates betweenthe PQL/MQL and the quadrature method. The Laplace approximation method, which is equivalent tothe adaptive Gauss-Hermite with 1 node, gives different estimates from the adaptive Gauss-Hermite with20 nodes revealing the importance of the number of nodes in quadrature methods.
DATASET 6. MARITAL SATISFACTION DATA 279
Table 6.6: PQL and MQL under REML and ML
Parameter PQL (REML) PQL (ML) MQL (REML) MQL (ML)
Int 3.053 (0.8803) 3.050 (0.8773) 2.853 (0.8596) 2.853 (0.8575)
year90 -0.620 (0.4397) -0.620 (0.4387) -0.546 (0.4179) -0.547 (0.4174)
year95 0.347 (0.4058) 0.346 (0.4052) 0.300 (0.3751) 0.300 (0.3750)
parent0 0.137 (0.4310) 0.137 (0.4306) 0.121 (0.3880) 0.121 (0.3881)
parent0×year90 -0.031 (0.4723) -0.031 (0.4718) -0.029 (0.4288) -0.029 (0.4289)
parent0×year95 -0.294 (0.5409) -0.293 (0.5403) -0.266 (0.4914) -0.266 (0.4915)
child90 0.084 (0.0958) 0.083 (0.0955) 0.066 (0.0941) 0.066 (0.0938)
yearsmarr90 -0.029 (0.0296) -0.029 (0.0295) -0.031 (0.0294) -0.031 (0.0293)
σ2
b1.664 (0.2396) 1.639 (0.2370) 2.396 (0.3247) 2.366 (0.3220)
Table 6.7: Gauss Hermite
Parameter Q = 3 Q = 5 Q = 10 Q = 20 Q = 50
Int 4.290 (1.2570) 4.358 (1.2366) 4.320 (1.2595) 4.354 (1.2535) 4.339 (1.2545)
year90 -0.724 (0.5634) -0.758 (0.5597) -0.729 (0.5677) -0.759 (0.5643) -0.755 (0.5658)
year95 0.419 (0.4717) 0.424 (0.4795) 0.471 (0.4825) 0.457 (0.4796) 0.458 (0.4805)
parent0 0.147 (0.4845) 0.173 (0.4801) 0.155 (0.4825) 0.151 (0.4824) 0.151 (0.4824)
parent0×year90 -0.018 (0.5337) -0.045 (0.5287) -0.025 (0.5319) -0.020 (0.5316) -0.020 (0.5315)
parent0×year95 -0.363 (0.5999) -0.387 (0.6021) -0.378 (0.6063) -0.372 (0.6064) -0.372 (0.6063)
child90 0.064 (0.1029) 0.190 (0.1386) 0.164 (0.1425) 0.153 (0.1364) 0.153 (0.1381)
yearsmarr90 -0.048 (0.0411) -0.053 (0.0408) -0.046 (0.0422) -0.046 (0.0424) -0.045 (0.0425)
σb 1.839 (0.1242) 2.131 (0.2011) 2.189 (0.2266) 2.142 (0.2178) 2.137 (0.2191)
−2` 1201.9 1205.3 1202.7 1202.9 1203.0
Table 6.8: Adaptive Gauss Hermite
Parameter Q = 3 Q = 5 Q = 10 Q = 20 Q = 50
Int 4.033 (1.1280) 4.246 (1.2074) 4.324 (1.2469) 4.338 (1.2543) 4.339 (1.2545)
year90 -0.741 (0.5269) -0.751 (0.5514) -0.755 (0.5636) -0.755 (0.5657) -0.755 (0.5658)
year95 0.431 (0.4609) 0.442 (0.4725) 0.456 (0.4792) 0.458 (0.4805) 0.458 (0.4805)
parent0 0.152 (0.4733) 0.151 (0.4783) 0.151 (0.4817) 0.151 (0.4824) 0.151 (0.4824)
parent0×year90 -0.022 (0.5214) -0.021 (0.5268) -0.020 (0.5307) -0.020 (0.5315) -0.020 (0.5315)
parent0×year95 -0.354 (0.5938) -0.364 (0.6005) -0.371 (0.6054) -0.372 (0.6063) -0.372 (0.6063)
child90 0.131 (0.1240) 0.145 (0.1322) 0.152 (0.1371) 0.153 (0.1381) 0.153 (0.1381)
yearsmarr90 -0.042 (0.0381) -0.044 (0.0409) -0.045 (0.0422) -0.045 (0.0425) -0.045 (0.0425)
σb 1.786 (0.1652) 2.007 (0.1799) 2.116 (0.2082) 2.137 (0.2189) 2.137 (0.2191)
−2` 1219.0 1205.2 1203.2 1203.0 1203.0
Table 6.9: PQL, MQL, Adaptive Gauss Hermite, Laplace
Parameter PQL MQL AQ (Q = 20) Laplace
Int 3.050 (0.8773) 2.853 (0.8575) 4.338 (1.2543) 6.058 (1.7343)
year90 -0.620 (0.4387) -0.547 (0.4174) -0.755 (0.5657) -0.757 (0.6993)
year95 0.346 (0.4052) 0.300 (0.3750) 0.458 (0.4805) 0.626 (0.5567)
parent0 0.137 (0.4306) 0.121 (0.3881) 0.151 (0.4824) 0.158 (0.5220)
parent0×year90 -0.031 (0.4718) -0.029 (0.4289) -0.020 (0.5315) -0.011 (0.5792)
parent0×year95 -0.293 (0.5403) -0.266 (0.4915) -0.372 (0.6063) -0.458 (0.6614)
child90 0.083 (0.0955) 0.066 (0.0938) 0.153 (0.1381) 0.219 (0.1843)
yearsmarr90 -0.029 (0.0295) -0.031 (0.0293) -0.045 (0.0425) -0.047 (0.0565)
σ2
b1.639 (0.2370) 2.366 (0.3220) 4.565 (0.9354) 16.536 (6.9512)
6. Test for the parent effect: The likelihood ratio test suggests that the parent effect on the maritalsatisfaction is not statistically significant (p-value = 0.8495).
DATASET 6. MARITAL SATISFACTION DATA 280
Part 4
1. Exploring incomplete data.In Table 6.10 an overview of the missingness patterns together with the frequencies with which they occuris shown. The group of dropouts is of considerable magnitude, while the intermittent missingness group ismuch smaller. They are all included into the analyses. We performed analyses on the continuous and binary
Table 6.10: Marital Satisfaction Data. Overview of missingness patterns and the frequencies with whichthey occur. ’O’ indicates observed and ’M’ indicates missing.
Missing Data Patterns
Group 1990 1995 2000 Freq Percent
1 O O O 268 23.39
Dropout
2 O O M 392 34.21
3 O M M 428 37.35
4 M M M 14 1.22
Intermittent Missingness
5 M O O 1 0.09
6 O M O 41 3.58
7 M O M 2 0.17
response. For the continuous response, we compared the complete case analysis with the direct likelihoodapproach and multiple imputation using mixed models. The results of a single imputation are shown forreasons of comparison. For the binary response, GEE on the completers, on the available cases, WGEE andmultiple imputation GEE were performed. In these analyses, the focus was not on model building but ratheron the comparison of the resulting estimates.
2. Continuous response using MIXEDA mixed model using ‘year’, ‘parent’ and their interaction for the mean structure and unstructured (‘parent’)and compound symmetry (‘year’) for the covariance structure is fitted using the complete cases (CC), directlikelihood approach, single and multiple imputation. Table 6.11 shows only moderate differences amongparameter estimates based on the various missing data approaches and the complete cases.
Table 6.11: Marital Satisfaction Data. Parameter estimates and standard errors based on a mixed modelusing the complete cases (CC), direct likelihood approach, single and multiple imputation.
Par. CC Direct Single Multiple
Likelihood Imputation Imputation
Year 1990 5.26(0.08) 5.19(0.04) 5.19(0.04) 5.19(0.04)
Year 1995 5.92(0.08) 5.93(0.05) 5.80(0.04) 5.82(0.05)
Year 2000 5.70(0.08) 5.60(0.07) 5.93(0.04) 5.90(0.06)
Parent 0 0.04(0.09) 0.06(0.07) -0.03(0.05) 0.04(0.09)
Year 1990 Parent 0 -0.08(0.09) -0.06(0.07) 0.03(0.06) -0.03(0.09)
Year 1995 Parent 0 0.06(0.09) -0.02(0.07) 0.14(0.07) 0.01(0.11)
3. Binary response using GEEA GEE analysis was performed on the completers and available cases and the resulting parameter estimatescompared with those based on WGEE, single and multiple imputation GEE. The mean structure used,
DATASET 6. MARITAL SATISFACTION DATA 281
consisted of ‘parent year birth parent*year parent*birth birth*year parent*birth*year’ where ‘year’ was takencategorical. Table 6.12 shows considerable differences among the different modelling approaches.By means of logistic regression a dropout model was fitted (Table 6.13). Among the variables considered:previous measurement, parent, year and birth; parent and year contributed significantly. For the now theother variables were retained in the model.
Table 6.12: Marital Satisfaction Data: GEE analyses based on completers, available cases, WGEE, singleand multiple imputation.
Par. CC Available WGEE Single (1) Multiple
Cases Imputation Imputation
Int -3.94(3.49) -1.79(2.41) -3.08(3.63) 0.74(2.37) -0.34(2.64)
Parent 0 8.29(3.64) 6.52(2.87) 14.03(4.90) 2.89(3.43) 2.88(3.62)
Year 1990 10.54(4.20) 1.44(2.64) 2.28(3.67) -1.68(2.80) -0.64(3.01)
Year 1995 11.11(4.99) 6.00(2.93) 10.78(4.85) 2.67(3.29) 2.79(3.36)
Birth 0.13(0.07) 0.08(0.05) 0.13(0.08) 0.05(0.05) 0.06(0.06)
Year 1990 Parent 0 -12.49(4.74) -4.20(3.08) -11.65(5.13) -0.44(3.95) -0.29(4.13)
Year 1995 Parent 0 -17.39(5.29) -3.98(3.90) -14.40(8.10) -0.04(4.55) -1.69(4.19)
Birth Parent 0 -0.18(0.07) -0.13(0.06) -0.29(0.10) -0.05(0.07) -0.06(0.08)
Birth Year 1990 -0.22(0.08) -0.04(0.05) -0.07(0.08) 0.01(0.06) -0.00(0.06)
Birth Year 1995 -0.22(0.10) -0.11(0.06) -0.21(0.10) -0.06(0.07) -0.06(0.07)
Birth Year 1990 Parent 0 0.26(0.10) 0.09(0.06) 0.25(0.11) 0.00(0.08) 0.01(0.09)
Birth Year 1995 Parent 0 0.36(0.11) 0.08(0.08) 0.29(0.16) -0.01(0.09) 0.03(0.09)
Table 6.13: Marital Satisfaction Data: Parameter estimates for the dropout model used to determine theweights for the WGEE.
Par. Estimate
Int -1.32(0.76)
Prev 0.23(0.25)
Parent 1 -4.33(0.71)
Year 1995 -0.33(0.16)
Birth 0.01(0.02)
4. Binary response using GLMMAs an alternative to GEE, a generalized linear mixed model was performed. Again considerable differencesare noted between the complete case estimates and the direct likelihood approach. Note that the estimatesare not comparable to those based on GEE.
5. General Conclusion:Further analyses are needed to investigate the nature of the missingness process and the appropriateness ofthe models used.
DATASET 6. MARITAL SATISFACTION DATA 282
Table 6.14: Marital Satisfaction Data: Parameter estimates based on a generalized linear mixed model usingcompleters and direct likelihood.
Par. CC Direct
Likelihood
Int 1.79(6.89) 0.81(4.77)
Parent 0 3.11(7.98) 2.94(6.26)
Year 1990 1.94(8.13) -1.68(5.03)
Year 1995 -0.07(9.31) 3.30(5.68)
Birth 0.05(0.14) 0.06(0.10)
Year 1990 Parent 0 2.57(10.44) 0.95(6.72)
Year 1995 Parent 0 2.76(11.99) 5.31(7.70)
Birth Parent 0 -0.07(0.16) -0.06(0.13)
Birth Year 1990 -0.05(0.16) 0.03(0.10)
Birth Year 1995 0.01(0.19) -0.05(0.11)
Birth Year 1990 Parent 0 -0.04(0.21) -0.02(0.14)
Birth Year 1995 Parent 0 -0.05(0.25) -0.12(0.16)
Variance 2.16(0.38) 2.13(0.21)