CIDS

Census interaction data: Census interaction data: from CIDS to CIDERfrom CIDS to CIDER

John Stillwell

School of Geography, University of Leeds, CIDS Director and UPTAP Coordinator

Third International Conference on Population Geographies organised by the RGS-IBG Population Geography

Research Group at the University of Liverpool, 19-21 June 2006

CIDSCIDS

• Census Interaction Data Service • ESRC/JISC funded Data Support Unit under the

Census Programme 2001-2006-2011• Provides registered users throughout the UK

with access to census origin-destination migration and commuting statistics

• Overall aim is to encourage more use to be made of these data sets

• Web-based Interface to Census Interaction Data (WICID) is the online access system

PresentationPresentation

1 IntroductionCensus interaction dataDevelopments from 1991CIDS data holdings

2 WICID: How does it work?Building queriesAnalysis tools

3 From CIDS to CIDERCIDS useageCIDER objectives

4 UPTAPOverview

1 Introduction:1 Introduction:Census interaction dataCensus interaction data

• SMS/SWS/STS involve migration and commuting flow data involving two geographies: origins and destinations

• Extremely rich data sets for use by researchers and practitioners

• Especially valuable because of lack of alternative data sources, especially below district scale

• Territorially comprehensive and reasonably reliable

• Tell us many things about mobility patterns, place connectivity and behavioural processes

Example:Example: Patterns of net migration for London Patterns of net migration for London boroughs, 2000-01boroughs, 2000-01

Aggregate rates of net migration show losses from all but three boroughs (& City of London)

Source: 2001 Census SMS level 1

The importance of disaggregating net The importance of disaggregating net migration for London boroughs, 2000-01migration for London boroughs, 2000-01

Net rates of migration for boroughs with the rest of GB

Net rates of migrationfor boroughs within London

Source: 2001 Census SMS level 1

Developments from 1991Developments from 1991

• Coverage of whole UK (for most interaction data)• 100% data for all interaction data including SWS• Data on journey to place of study in Scotland (STS)• Student migration to, at and from university• Richer data: more tables and detail within tables• Additional sets of tables at ‘output area’ level• Imputation of missing data on workplace and migrants’

origins (if not stated and not ‘no usual address 1 yr ago’• New concept of ‘moving groups’ in SMS• Different approach to disclosure control

In comparison with 1991 Census, there are a similar In comparison with 1991 Census, there are a similar number of tables but: (1) considerably more counts in 2001, number of tables but: (1) considerably more counts in 2001,

(2) all the counts are 100% in 2001, (3) OA level(2) all the counts are 100% in 2001, (3) OA level

Data sets

Level 1 (District)

Level 2(Ward)

Level 3(OA)

2001 SMS

10 tables, 996 counts

5 tables, 96 counts

1 table, 12 counts

1991 SMS


2 tables, 12 counts

-

2001 SWS



1 table, 36 counts

1991 SWS*

- Set C: 9 tables, 274 counts

-

2001 STS

7 tables, 1,176 counts


1 table, 50 counts

* 10% sample

Geographical units used in 2001 Geographical units used in 2001 SMS/SWS/STSSMS/SWS/STS

Country Level 1 Level 2 Level 3

England London Boroughs (33), Metropolitan Districts (36), Unitary Authorities (46), Other Local Authorities (239)

CAS wards (7,969)

Output areas (165,665)

Wales Unitary Authorities (22) CAS wards ( 881) Output areas (9,769)

Scotland Council Areas (32) ST wards ( 1,176) Output areas (42,604)

Northern Ireland

Parliamentary Constituencies (18)

CAS wards (582 ) Output areas (5,022)

Total Districts (426) Interaction wards (10,608)

Output areas (223,060)

Adjustment for disclosure control in 2001Adjustment for disclosure control in 2001

• Various methods used by ONS in 2001– minimum thresholds of people and

households before the release of data– record swapping between areas– small cell adjustment method (SCAM)

• SCAM assumed to adjust values of 1 and 2 to values of 0 and 3

• Significant impact on flows, especially at OA level

How many UK internal migrants? How many UK internal migrants?

Seven different counts of total migration in 2001 SMS for 2000-01 period:

Level from which total derivedTable Level 1 Level 2 Level 3

Table 1 (Total): 6,202,016 6,267,740 6,164,996

Table 2 (Family status): 6,204,876 na na

Table 3 (Ethnicity): 6,206,216 6,190,926 na

Table 4 (LTL illness): 6,205,128 na na

Source: 2001 Census SMS tables

CIDS interaction data holdingsCIDS interaction data holdings

Type Migration Commuting

2001

Raw SMS (Levels 1, 2, 3) SWS, STS (Levels 1, 2, 3)

1991

Raw SMS (Sets 1 and 2), Table 100 SWS (Sets A, B, C)

Derived MIGPOP, SMSGAPS

Derived SMS Set 1 for 2001 areas SWS Set C for 2001 areas

1981

Raw SMS Set 2 (County and region) SWS Set C (County and region)



2 WICID2 WICIDCIDS homepage: http://cids.census.ac.uk/CIDS homepage: http://cids.census.ac.uk/

WICID home pageWICID home page

WICID general query interfaceWICID general query interface

See paper in Environment and Planning A (2003) for further details

Selection of origins or destinationsSelection of origins or destinationsWhen choosing origins or destinations, users are confronted with a set of alternative selection tools

Map Map selection selection window window in WICIDin WICID

WICID uses Post GIS extendedPostgresSQLdatabase and MapServerlibrary components

Example of a query: Example of a query: to select flows to City of to select flows to City of London from districts in SE and other regionsLondon from districts in SE and other regions

Analytical Analytical ToolsTools

Some basic statistics

Suite of indicatorsSome of which require additional data: e.g. distances populations at risk

Assembly of PARs is currently underway for 2001 data sets: needs specially commissioned counts for some variables

Migration Migration effectiveness effectiveness by ethnic by ethnic group for group for regions, regions,

2000-012000-01

Connectivity of London boroughs by ethnic groupConnectivity of London boroughs by ethnic group

0.00

0.20

0.40

0.60

0.80

1.00

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33

Boroughs ranked by index

Ou

tflo

w C

I (w

ith

in G

L)

White

Indian

Pakistani and OSA

Chinese

Black

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33

Boroughs ranked by index

In-c

om

mu

tin

g C

I (W

ith

in G

L)

White

Black

Indian

Pakistani and OSA

Chinese

Source: 2001 Census SMS and SWS level 1

Out-migration In-commuting

3 From CIDS to CIDER (Centre for 3 From CIDS to CIDER (Centre for Interaction Data Estimation and ResearchInteraction Data Estimation and Research

• CIDS useage statistics

0

200

400

600

800

1000

1200

2003Q1 2003Q2 2003Q3 2003Q4 2004Q1 2004Q2 2004Q3 2004Q4 2005Q1 2005Q2 2005Q3

2001 SWS / STS

2001 SMS

1991 Table 100

1991 SWS

1991 SMS

1981 SWS

1981 SMS

Objectives of CIDERObjectives of CIDER

• To continue delivery of a high quality service• To redesign WICID database structure and

develop user interface• To gather/estimate further UK census-based

data sets (e.g. commissioned tables, SOA-SOA flows)

• To expand WICID to include UK non-census data sets (e.g. from NHSCR, patient registers, HESA)

• To provide training, to upgrade documentation and to disseminate

• To advise on 2011 Census and prepare for inclusion of interaction data sets in WICID

AcknowledgementAcknowledgement

CIDS is funded by the ESRC/JISC under Census Programme Research Grant

H507255177

CIDER is funded by the ESRC under Census Programme Research Grant

RES-348-25-0005

4 UPTAP: Overview4 UPTAP: Overview

Primary aims of UPTAPPrimary aims of UPTAP

• To build capacity in secondary data analysis

• To promote the use of large-scale social science data sets, both qualitative and quantitative

• To improve our understanding of demographic trends and processes which affect society and the population

• To build capacity in secondary data analysis amongst new and mid-career researchers

• To spread knowledge and use of secondary analysis through and beyond the social science community

• To add value to the ESRC investments in the collection, preservation and promotion of large-scale national data sets by encouraging their use and exploitation

• in the longer term, to maximize the knowledge gained about economic and social change from secondary data analysis

Principal objectives of UPTAPPrincipal objectives of UPTAP

• ESRC National centre for Research Methods (NCRM)

• ESRC Research Methods Programme

• ESRC Researcher Development Initiative

• ESRC Census Programme

• ESRC National Centre for e-Social Science (NCeSS)

Other ESRC initiativesOther ESRC initiatives

• 4 Postdoctoral Fellowships• 7 Mid-career Research Fellowships

(including 1 User Fellowship)• 7 Small Research Grants• 3 larger capacity building projects

(with linked studentships)

• In total, 21 projects involving 31 researchers

Initial UPTAP awardsInitial UPTAP awards

THEMESTHEMES

• Demographic change - Residential change

• Fertility - Motherhood - Childlessness• Living arrangements - Childcare• Cohabitation - Mobility• Health - Wellbeing - Employment• Education• Identity - Ethnicity - Segregation• Social and political values

• 1 October 2005Saffron Karlsen and James Nazroo: Being a Muslim in Europe: attitudes and experiences Yaojun Li and Anthony Heath: Socio-economic position and political support of the BMEs in Britain 1971-2004 Paul Norman: The micro-geography of demographic change 1991-2001

• 1 November 2005Roona Simpson: Delayed childbearing and childlessness in Britain : the 1958 and 1970 cohorts compared Eric Kaufman: A dying creed? The demographic contradictions of liberal capitalism

Those projects underway in 2005Those projects underway in 2005

Those projects commencing on 1 Jan 2006Those projects commencing on 1 Jan 2006• Ernestina Coast: Currently cohabiting: relationship attitudes, intentions

and behaviour

• Shu-Li Cheng: The impact of educational qualifications on trends in leisure activities

• Dan Vickers: The changing residential patterns of the UK 1991-2001 • Dimitris Ballas: Exploring geographies of happiness and well-being in

Britain

• Daniel Guinea-Martin: Trends in gender and ethnic occupational segregation in England and Wales: longitudinal evidence

• Kirstine Hansen, Heather Joshi and Denise Hawkes: Motherhood and child outcomes: the consequences of the timing of motherhood and mothers' employment on child outcomes

• Sarah Smith, Anita Ratcliffe and Mike Brewer: Understanding the effect of public policy on fertility; secondary data analysis

• Harriet Young and Emily Grundy: Living arrangements, health and well-being: a European perspective

Those projects commencing in last 6 monthsThose projects commencing in last 6 months

• 1 February 2006Paula Surridge: The making of social values: social attitudes and social change

• 1 March 2006Patrick Sturgis and Nick Allum: Social and political trust: a longitudinal and comparative perspective

• 1 June 2006Paul Boyle, Vernon Gayle, Elspeth Graham and

Ali Zohoor: Does stepparenting influence mental health?

• 1 August 2006

Alison Smith: Intergenerational contributions to childcare across

Europe Oliver Duke-Williams: Links between internal migration, commuting and inter-household relationships

• 1 October 2006Michelle Jackson: Investigating inequalities in educational attainment

Gopalakrishnan Netuveli: Treating longitudinal data as longitudinal: comparing models to describe employment status and health trajectories in British Household Panel Survey

• 1 May 2007Claudia Thomas: How does employment affect cardiovascular risk? A life-course approach in the 1958 cohort

Those projects yet to commenceThose projects yet to commence

UPTAP web site: www.uptap.netUPTAP web site: www.uptap.net

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