Research and teaching with the SHS data

Gillian Raab

Professor of Applied Statistics

Napier University

Welcome to SHS lite!

Lots of good points

An excellent start

But it could go even further

Summary

• Some recent research projects

• Some thoughts on the present state of survey research

• An introduction to a web resource being developed at Napier along with the National Centre for Social Research

Research projects using SHS

• Older people• Training in the workplace• Income distributions

– SHS compares favourably with the FRS

– Sample size is larger

– This results in an improvement by a factor of two in precision

– BUT questions less detailed and not everyone is asked

– Something COULD be done about this

Differences between Scottish surveys and FRS

-7,000

-6,000-5,000

-4,000

-3,000

-2,000-1,000

0m

ean

5th

10th

25th

med

ian

75th

90th

95th

SHS-HBAI SHCS-HBAI

Possible need to improve the weighting of the SHS age distribution for single person households

0.0%

2.0%

4.0%

6.0%

8.0%

10.0%

12.0%

14.0%

16.0%

15-1

9

20-2

4

25-2

9

30-3

4

35-3

9

40-4

4

45-4

9

50-5

4

55-5

9

60-6

4

65-6

9

70-7

4

75-7

9

80 an

d ov

er

hbai shs shcs hbai unweighted

SHS features

• Complicated design

• Uses several design features to get a better sample

• Needs to be analysed with weighting

• Do we do all of this justice in the way we analyse the data?

We do need to weight

10.00 15.00 20.00 25.00 30.00 35.00 40.00

Glasgow City

West Lothian

North Lanarkshire

Scottish Borders

Orkney

Aberdeenshire

East Dumbartonshire

East Renfrewshire

weighted unweighted

But we should really do more than this

• Methods for designing surveys were developed in the 1950s

• There were a parallel developments in survey analysis at the same time

• But most of the expertise for this (at least in the UK) stayed within survey organisations

Packages for survey analysis

• Until recently general packages pretty limited and had few methods

• Now much better• SPSS complex surveys was launched this

year with version 12 of SPSS– But it will have more facilities– It costs a little extra– And is not very easy to use

PEAS project• Funded under the ESRC research methods

programme• to develop a Practical web-based resource which

will take the survey analyst through Exemplars of the use of different methods that are currently available for the Analysis of complex Surveys

• The web site also contains a guide to survey design and analysis linked to the exemplars

What will these procedures do?• Design effects – design factors

– Tell you how precise your survey estimates are

• Can get them from tables– But tables are limited– They are a nuisance to use– Don’t work for anything but the simplest cases

• Much better if your analysis package will give you the answer right away including– Tables with chi square tests– Confidence intervals– Correct regressions

Design factors vary from close to 1.0 in cities to over 1.6 in Orkney

Largely due to clustering in rural areas

Site is still being finalised

• We would welcome constructive feedback

• Temporary site is

http://www.napier.ac.uk/depts/

fhls/CommHealth/staff/gillianr/peas/home.htm