1 kuo-hsien su, national taiwan university nan lin, academia sinica and duke university measurement...
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3 Differences between the sets of accessed positions during two interviews may reflect… Genuine changes in network Measurement Error Observed change of accessed positionsTRANSCRIPT
1Kuo-hsien Su, National Taiwan UniversityNan Lin, Academia Sinica and Duke University
Measurement of Social Capital: Recall Errors and Bias Estimations
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-20 -10 0 10 20Differences in number of positions accessed (wave II - wave I)
Change in number of positions accessed from wave I to wave II (N=2,707 respondents)
No change : 12%
Decrease : 52.9%
Increase : 35%
3
Differences between the sets of accessed positions during two interviews may reflect…
4Motivations Measurement instability poses a serious
challenge to the study of network changes. Need a clear measurement or better
understanding of the possible sources of error. The two periods panel survey provided an
opportunity (1) to model factors associated with changes in accessed position (2) to detect whether the respondent forgot a subsequently/previously named contact .
5Prior research Forgetting is a pervasive
phenomenon in the elicitation of network contacts.
Research on forgetfulness has been disproportionately based on name generator instrument.
Little research on the reliability of position generator.
6Tasks
7Data Social Capital Project: the Taiwan
Survey, conducted in late 2004 and 2006 Consists of 1,695 men and 1,585 women
aged 20-65.
8Problem of Non-response
Wave I2004N =
3,280
Wave II2006N =
2,710Re-interview = 82.6%Non-response = 17.4%
9
Table 1. Characteristics of the follow-up and non-response sub-sample Full sample Follow-up Non-response
sample (N=3280) (N=2710) (N=570) Mean % Mean % Mean %Gender Male 51.7% 51.5% 52.5% Female 48.3% 48.5% 47.5%Age 41.3 41.7 39.5 Years of schooling 11.7 11.7 11.8 Marital Status Single 23.9% 22.8% 29.1% Married/cohab 70.2% 71.4% 64.4% Widow/divorced 6.0% 5.8% 6.5%Network resource indices Extensity 8.5 8.5 8.2 Upper reachability 62.4 62.8 60.4 Range of prestige 36.7 37.0 35.1
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Three types of research designs (Brewer, 2000).
11Limitations of our data Our survey was not designed to
examine forgetting specifically. No recognition data or objective
records to compare with. Two years interval is too long: Test-
retest design is usually within a very short time interval.
12
Revised method C: Comparison of accessed positions elicited in two separate interviews
Wave II2006
Wave I2004
How many years have you known this person ?
2005
Forgetting = (Contact mentioned in wave II but not mentioned in wave I) AND (duration >= 3 years)Assumption: durations reported in wave II are more or less accurate.
Whether the respondent forgot a subsequently named contact?
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Coding scheme for tie changes
Wave II (2006)NO YES
Wave I (2004)
NO
(1) Consistent “NO”
(2) New contacts (less than 3 years)
(3) Forgetting at wave I (more than 3 years)
YES(4) Lost
contact /Forgetting at wave II
(5) Consistent “YES”
The distribution of length of relationship of forgotten ties (N=4,332 dyads, 7.3%)0
.02
.04
.06
.08
.1D
ensi
ty
0 20 40 60Length of relationship (in years)
The average duration of ties forgotten is 13 years
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How much does the respondent forget?Wave I Wave II know more
than 3 years? Categories N Percent
YES YES Consistent "YES" 14,330 49.9%
NO YES NO New contact 1,240 4.3%
YES Forgotten at wave I 4,332 15.1%
YES NO Contact lost/Forgotten at wave II
8,794 30.7%
Total 28,696 100%
approximately 15% of forgetting
Unique= 51.1%
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Distribution of respondents by number of ties forgotten (N=2707 respondents)0
1020
3040
Per
cent
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20Number of forgotten ties in wave 1
35.6% of the respondents did not forget any ties
64.4 %of the respondents failed to mention at least one contact, with an average of 1.6 forgotten ties per respondent.These numbers suggest that
forgetting a contact was not a rare occurrence.
17Analytical Strategies
What factors are associated with forgetting?
Unit of analysis: person-contacts dyads
Model : Multilevel logit
Whether “forgetting” affects estimates of network resources ?
Unit of analysis: person
Model predicting “forgetting”
Analysis for the effect of forgetting on estimates of accessibility
18Sample A multi-level logit approach The models estimate the odds of “forgetting”
versus “not forgetting”; the reference population consisted of all contacts mentioned in the first interview (2004).
Data structure
Positions nested within individuals
LEVEL 2 LEVEL 1
The final sample consists of 2,682 respondents and 28,343 person-contact dyads.
The multi-level approach requires us to transform the individual-based data to person-contacts observations.
20Variables Level 2 (respondent level):
Age Years of schooling Marital status (married) Employment status (employee) Occupational prestige score Size of daily contact
21Variables
Level 1 (ties level): Type of relationships
Group into six categories: kin, neighbor, school tie, work-related ties, friends, indirect tie
Length of relations (in years) Closeness Gender homophily Status difference
Status distance = absolute difference between respondent’s prestige score and contact’s prestige scores
Status disparity = respondent’s prestige score – contact’s prestige score
Descriptive statistics (individual level)Level-2 Total Male Female (N=2676) (N= 1383) (N=1293)Age(in years) 41.62 41.46 41.79
(11.66) (11.62) (11.70)Years of education 11.77 12.30 11.19
(4.23) (3.75) (4.63)Marital statussingle 0.23 0.25 0.21 divorced/widowed 0.06 0.03 0.09 married 0.71 0.72 0.71 Employment statusemployee 0.72 0.68 0.76 self-employed/employer 0.18 0.23 0.12 part-timer 0.03 0.03 0.03 family worker 0.08 0.05 0.10 Occupation prestige score 39.88 41.26 38.39
(12.91) (13.13) (12.50)Size of daily contacts 3.42 3.52 3.31
(1.36) (1.31) (1.41)
Descriptive statistics (dyad level)Level-1 Total Forgetting Not
forgetting (N=27,103) (N=4,315 ) (N=22,788)Type of relationshipkin 0.21 0.24 0.21 neighbor 0.07 0.09 0.07 school tie 0.07 0.07 0.08 work-related ties 0.35 0.42 0.33 friends 0.24 0.12 0.26 indirect tie 0.05 0.07 0.05 Same sex 0.61 0.60 0.61 Length of relationship 12.89 12.95 12.88
(11.92) (11.98) (11.91)Closeness 3.46 3.34 3.49
(0.99) (0.99) (0.99)Status Distance 15.79 16.74 15.61
(11.66) (12.21) (11.54)Status Disparity -3.56 -5.89 -3.12 (19.30) (19.87) (19.16)
24 MODEL (1)Level-2 Model
Intercept -1.197***Female (male) -.146***Age (in years) .000Years of schooling -.054***Marital status (married)
Single .105+Divorced/widowed -.168+
Employment status (employee)Self-employed/employer -.080Part-timer -.076Family worker -.048
Occupation prestige scores -.007***
Size of daily contacts -.125***
Multi-level model predicting “forgetting”(level-2 model)
25
Multi-level model predicting “forgetting” (Level-1 model)
MODEL (1) MODEL (2)Level-1 Model
Type of relationship (work-related ties)
Kin .100* .100*
Neighbor .015 .011School ties -.196*** -.197***
Friends -.807*** -.804***
Indrect ties .096 .104+
Same sex -.039+ -.106***
(same-sex)×female .122**
Length of relationship -.008*** -.007***
Closeness -.173*** -.174***
Status Distance .007*** .011 ***
(status distance)×female -.007***
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Multi-level model predicting “forgetting” (Level-1 model)
MODEL (3) MODEL (4)Level-1 Model
Type of relationship (work-related ties)Kin .108* .107*
Neighbor .022 .020School ties -.197*** -.200***
Friends -.814*** -.812***
Indrect ties .098+ .104+
Same sex -.040+ -.106***
(same-sex)×female .119*
Length of relationship -.008*** -.008***
Closeness -.179*** -.181***
Status disparity -.002** -.004***
(status disparity)×female .004**
27Findings Recall error may not be random. Forgetting is more likely among weak
ties. How does recall error affect the
estimation of network-driven indices ?
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Table 4. Discrepancy between “true” (corrected) and “observed” (raw) network resources indices Corrected
scoreRaw score Differences t-test
Extensity Mean 9.9 8.5 1.38 39.2 SD 5.5 5.5 Range Mean 40.6 36.7 3.92 25.8 SD 16.8 18.6 Upper reachability Mean 65.2 62.4 2.83 19.3 SD 15.2 17.6
Because forgetting is more likely among weak ties, position-generator underestimate embedded network resources.
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Table 5. Correlations between “true” (corrected) and observed (raw) network resources indices at wave I (N=3,272)
Corrected indices Raw indices at wave I
Extensity Range Reachability Extensity Range
Corrected indices
Extensity -- Range .817 Reachability .692 .886
Raw indices at
wave I
Extensity .934 .745 .632 Range .792 .884 .776 .832
Reachability .674 .804 .880 .694 .865
30Conclusions Forgetting a contact was not a rare
occurrence; Recall error is largely nonrandom. Status difference appears to govern the
recall process. Position generator systematically
underestimates network-driven resource indices.