Hints and Tips on using the Scottish Household Survey data

Steven Hope, Ipsos MORI

Mairi MacAskill, SHS Project Manager

Background

• Over the past eight years the survey has collected data on 120,000 households

• The data are considered to be complex to analyse – SHS Lite

• Thousands of variables every year

• However there is get potential for secondary analysis

Limitations

• Sample Survey

• Covers private households only

• Is not designed to give results below local authority level

• More sophisticated statistical analysis is problematic due to sample design

• Limited on some topics – e.g. income

SHS Lite vs Full SHS

• Intended as an easier entry point to SHS analysis

• Key differences– Multi-code and ‘loop’ variables summarised– Many detailed variables removed

• Individual components of income• Details of all household members

– Variables organised into analysis sets

Unit of analysis

• Know what level the information was collected at– Household– Person– Random Adult– Random Schoolchild

Data StructureThe Data Archive data is in one flat file –

i.e. one record for each household;

• When analysing Random Adult data there will be around 10% of cases missing

• When analysing at person level the data will have to be transposed

Weighting

• Almost all analysis needs to be weighted– La_wt – local authority weight, to be used for

household analysis– Ind_wt – Individual weight, to be used for adult level

analysis– Other weights for random schoolchild and journey or

stage level analysis

• Mixing variables– Variation in internet use by tenure – tenure is a

household characteristic. Internet use is collected from the random adult. Weighting?

Routing & Streaming

Respondents can be either• Routed around – the question is not

appropriate based on previous answers

• Streamed out – question asked of a sub-sample to save space– Pre-2007 – variable “RANVER”– 2007 onwards – variable “STREAM”

Using SPSS syntax

• Many advantages over the menu system– Analysis can be checked and repeated– Previous analysis can be edited and reused– Faster – run batches on one pass of the data– More options available

• Paste from menus to see structure

• Copy and amend annual report syntax

Questions?