Census interaction data from CIDS to CIDER John

Census interaction data: from 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

CIDS • 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

Presentation 1 Introduction Census interaction data Developments from 1991 CIDS data holdings 2 WICID: How does it work? Building queries Analysis tools 3 From CIDS to CIDER CIDS useage CIDER objectives 4 UPTAP Overview

1 Introduction: Census 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: Patterns of net migration for London boroughs, 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 migration for London boroughs, 2000 -01 Net rates of migration for boroughs within London Net rates of migration for boroughs with the rest of GB Source: 2001 Census SMS level 1

Developments 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 a similar number of tables but: (1) considerably more counts in 2001, (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 11 tables, 94 counts 2 tables, 12 counts - 2001 SWS 7 tables, 936 counts 6 tables, 354 counts 1 table, 36 counts 1991 SWS* - Set C: 9 tables, 274 counts - 2001 STS 7 tables, 1, 176 counts 6 tables, 478 counts 1 table, 50 counts * 10% sample

Geographical units used in 2001 SMS/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 Output areas (10, 608) (223, 060)

Adjustment 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? Seven different counts of total migration in 2001 SMS for 2000 -01 period: Table Level 3 Table 1 (Total): Level from which total derived Level 1 Level 2 6, 202, 016 Table 2 (Family status): 6, 204, 876 Table 3 (Ethnicity): 6, 206, 216 Table 4 (LTL illness): 6, 205, 128 6, 267, 740 6, 164, 996 na 6, 190, 926 na na na Source: 2001 Census SMS tables na

CIDS 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 Derived MIGPOP, SMSGAPS Derived SWS (Sets A, B, C) 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) Derived SMS Set 2 for 2001 areas SWS Set C for 2001 areas Derived SMS Set 2 for 1991 areas SWS Set C for 1991 areas

2 WICID CIDS homepage: http: //cids. census. ac. uk/

WICID home page

WICID general query interface See paper in Environment and Planning A (2003) for further details

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

Map selection window in WICID uses Post GIS extended Postgres. SQL database and Map. Server library components

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

Analytical Tools Some basic statistics Suite of indicators Some 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 effectiveness by ethnic group for regions, 2000 -01

Connectivity of London boroughs by ethnic group Out-migration In-commuting Source: 2001 Census SMS and SWS level 1

3 From CIDS to CIDER (Centre for Interaction Data Estimation and Research • CIDS useage statistics

Objectives 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

Acknowledgement CIDS is funded by the ESRC/JISC under Census Programme Research Grant H 507255177 CIDER is funded by the ESRC under Census Programme Research Grant RES-348 -25 -0005

4 UPTAP: Overview

Primary 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

Principal objectives of UPTAP • 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 largescale 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

Other ESRC initiatives • 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 (NCe. SS)

Initial UPTAP awards • 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

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

Those projects underway in 2005 • 1 October 2005 Saffron 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 2005 Roona 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 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 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 wellbeing: a European perspective

Those projects commencing in last 6 months • 1 February 2006 Paula Surridge: The making of social values: social attitudes and social change • 1 March 2006 Patrick Sturgis and Nick Allum: Social and political trust: a longitudinal and comparative perspective • 1 June 2006 Paul Boyle, Vernon Gayle, Elspeth Graham and Ali Zohoor: Does stepparenting influence mental health?

Those projects yet to commence • 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 2006 Michelle 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 2007 Claudia Thomas: How does employment affect cardiovascular risk? A life-course approach in the 1958 cohort

UPTAP web site: www. uptap. net