Secondary Data Analysis Using the Census

Stephen Drinkwater

WISERDSchool of Business and Economics

Swansea University

Background• Although infrequent, the Population Census constitutes a

very important resource for secondary data analysis

• Particularly useful for examining small geographical areas or demographic groups

• Can also be used to examine changes over time, although can only provide snapshots

• Questions and geography also vary across Censuses and UK-wide comparisons can be tricky

• But the 2011 Census is likely to be of most interest => headline figures due to be released in mid-2012

ESRC Census Programme• Some forms of Census data can be downloaded directly from

ONS websites (e.g. Neighbourhood Statistics and NOMIS)

• Academic analysis of Census data for is facilitated by the ESRC funded Census Programme

• The 2006-11 programme was recently evaluated by WISERD

• The programme supports a range of data units which enable academics and students access to several different types of Census data => only need to register with the CRS to do so

• For more details see www.census.ac.uk

Census Units and Data• CDU => Aggregate data: Key Statistics and Census Area

Statistics (close links with UKBorders geo-data)

• CCSR => Census Microdata (SARs in 1991 , SARs, SAM and CAMS in 2001)

• CIDER => Census Flow data on Migration and Commuting

• CELSIUS => Census Longitudinal Study for England and Wales which links 1% of individual records back to 1971

• Other Census data not directly relevant to Wales: NILS (provided through NILS-RSU) SLS (provided through the LSCS)

Informal Caring in the Census

• A question on the provision of informal (unpaid) care was included in the Census for the first time in 2001

• “Do you look after, or give any help or support to family members, friends, neighbours or others because of long-term physical or mental ill-health or disability or problems related to old age?”

Respondents also asked to indicate how many hours they roughly provided per week: No (0); Yes (1-19, 20-49 or 50+)

• These responses were then used to create two variables in Census microdata: a banded one on time spent per week caring and on the number of carers in the household

Research on Informal Caring using 2001 Census Data

• Several studies have used different types of Census data to examine a range of issues connected to informal caring:

Shaw and Dorling (2004) use aggregate Census data for UAs/LAs in England and Wales and find a positive relationship between informal care provision and health need (limiting illness/disability)

Hancock et al. (2009) examine gender differences in care using the SARs and report that caring is much higher for females but that there are differences by age (care increases for elderly males)

Norman and Purdham (2010) analyse the SAM for PCTs in England and Wales and find very different geographies of care for demographic groups and for within and outside household

Drinkwater (2011) uses the SAM to examine the relationship between informal caring and labour market outcomes, focusing specifically on the South Wales Valleys

Gives us a pretty good picture of spatial differences in caring

Limiting long term illness in England and Wales, 2001

Source: Norman and Purdham (2010)

Informal care in England and Wales, 2001

Source: Norman and Purdham (2010)

Informal care within the household in England and Wales, 2001

Source: Norman and Purdham (2010)

Informal care outside the household in England and Wales, 2001

Source: Norman and Purdham (2010)

Informal Care and Labour Market Outcomes (Drinkwater, 2011)

• Uses 2001 Small Area Microdata Sample (SAMS) 5% sample of all Census returns => almost 3 million

observations across the UK Can be used to identify separate LA/UAs Also contains a reasonable range of socio-economic controls

but quite a bit of detail has been suppressed (for confidentiality reasons) e.g. age is banded

Can only focus on employment, hours of work and occupation in terms of labour market outcomes since no earnings information available in Census

Distribution (%) of Hours of Informal Care: 2001

•

• Greater number of hours spent providing care in Wales => Northern Ireland is the only region where caring is higher

• Especially high for females and in the Valley UAs

• Highest in Neath & Port Talbot and Merthyr Tydfil, especially for women. Relatively high in Caerphilly and Torfaen for men

0 <20 20-49 50+ 0 <20 20-49 50+Valley UAs 86.0 9.0 1.8 3.2 81.6 10.8 2.7 4.8Non-Valley UAs 88.2 8.2 1.4 2.2 83.4 10.7 2.2 3.7Wales 87.7 8.4 1.5 1.7 83.0 9.9 1.7 4.0UK 89.6 7.3 1.1 1.7 85.7 9.9 1.7 2.7

FemalesMales

Labour Market Outcomes by Hours of Care: 2001

IRC RoE SWV RoW IRC RoE SWV RoWInactivity Rate: 0 hours of care 10.2 14.2 23.1 16.8 23.4 24.5 33.7 26.4Inactivity Rate: 1-19 hours caring 12.5 14.6 18.8 15.8 23.4 22.2 28.6 23.9Inactivity Rate: 20-49 hours caring 23.4 30.1 38.8 32.6 41.0 43.5 49.8 42.7Inactivity Rate: 50+ hours caring 41.8 52.2 60.7 51.9 62.5 63.6 68.0 62.4Employment Rate: 0 hours of care 84.2 79.9 70.4 77.3 73.1 71.7 62.1 69.9Employment Rate: 1-19 hours caring 83.4 80.8 75.9 79.7 73.6 74.9 68.6 73.6Employment Rate: 20-49 hours caring 69.5 63.3 56.5 61.3 55.5 53.5 47.5 54.2Employment Rate: 50+ hours caring 53.5 42.9 33.3 43.8 35.6 34.6 30.5 35.7Part-time Rate: 0 hours of care 8.8 8.8 7.1 9.7 36.6 43.1 40.8 43.1Part-time Rate: 1-19 hours caring 10.8 9.9 6.5 10.2 45.4 47.8 44.2 46.9Part-time Rate: 20-49 hours caring 11.1 11.2 7.6 10.3 46.6 53.3 48.9 51.7Part-time Rate: 50+ hours caring 10.9 11.8 8.1 10.9 57.1 59.8 55.1 51.2

Males Females

Probit Estimates of Impact of Intensive Levels of Care Provision (20+ hours per week) on

Labour Market Outcomes

M.E. S.E. N M.E. S.E. N M.E. S.E. NLESE -0.147 0.006 306788 -0.195 0.005 292610 0.076 0.008 211144ROE -0.194 0.005 419753 -0.208 0.004 392114 0.074 0.006 277178SVW -0.224 0.026 11043 -0.207 0.021 10406 0.085 0.031 6333ROW -0.192 0.017 30541 -0.205 0.013 28750 0.041 0.019 19731

FemaleEmployment

MalePart-time Females

Conclusions• Hopefully shown a useful example of how the Census can be

used to examine an important contemporary issue Interesting to see how things have changed by 2011 as the

same question on caring was asked

• 2001 data show that informal caring is much higher in Wales than in the rest of UK (except NI) especially in the Valleys

Fairly similar effects of caring on employment and hours of work in the Valleys compared to rest of the UK/Wales but some differences and given that the incidence of care is much higher then informal caring has a larger impact

• But difficult to use Census data to control for the possible endogeneity of caring and labour market outcomes