1. Web Access to Census Interaction Data John Stillwell and Oliver Duke-Williams Centre for Computational Geography University of Leeds, Leeds LS2 9JT Paper presented at XVI AESOP Congress, Track 6: Information Technology in Planning, Volos, 10-15 July 2002

2. Focus §The provision and development of a Census Interaction Data Service (CIDS) §The development of a web-based information system (WICID) that allows researchers to extract data on interaction flows between origins and destinations

3. Presentation §The challenge: aims and objectives §Census based interaction data sets §Importance of interaction data in planning §System architecture and metadata structure §Features of the interface §Some examples of data extraction

4. Acknowledgements §Funded by ESRC and JISC under the 2001 Census of Population Programme (Award number H507 255177) §Began: 1 August 2001 §Ends: 31 July 2006 §Paul Boyle and Zhiqiang Feng, University of St Andrews

5. The Challenge §Aim is to increase the use of the Origin- Destination (interaction) data sets that will be produced as outputs from the 2001 UK Census (as well as the equivalent special migration and commuting data sets produced from 1991 and 1981 censuses)

6. Objectives §To provide users with access to existing census based interaction data sets (for 1991 and 1981) via the Internet §To develop an ‘user-friendly’ interface for query building and data extraction §To develop a flexible system that allows new data sets (e.g. 2001 Census interaction data) to be added without any major system redesign

7. Objectives §To allow users the option of constructing queries that involve the selection of origin and destination areas at different spatial scales §To produce a library of popular sub-sets of interaction data for quick extraction and downloading §To provide facilities to download the data in alternative formats

8. Interaction Data Sets for 1991 Original data sets §SMS Set 1 (2 tables, 12 counts, wards) §SMS Set 2 (12 tables, 93 counts, districts) §SWS Set C (9 tables, 274 counts, wards) §Table 100 (2 tables, 47 counts, districts) Derived data sets §SMS Set 1 Tables 3-10 (adjusted by Rees and Duke- Williams) so-called SMSGAPS §SMS Set 1 Table 3 (adjusted by Simpson and Middleton) so called SMS-MIGPOP

9. Interaction Data Sets for 1981 §1981 SMS Set 2 (Male and female migrants between wards in 1991) §1981 SWS Set C (Five tables - 172 counts - of journey to work flows between wards in 1991) §all re-estimated for 1991 ward geography by Boyle and Feng as part of a Census Development Programme project

10. Importance of interaction data in planning §Interaction data sets are very important because they provide information on migration and commuting flows between small areas (wards) §e.g. migration data used for population estimation and projection by central and local government agencies §e.g. commuting data used to define TTWAs and in transport planning

11. System Architecture

12. Metadata Structure

13. Features of the WICID Interface Login in screen

14. WICID General Query screen

15. WICID Area Selection Tools

17. WICID List Area Selection Tool

18. WICID Data Selection Tools

19. WICID Data Selection Options

20. WICID Table Selection for 1991 SMS 2

21. WICID Variable Selection with Table 1 of 1991 SMS 2

22. WICID Data extraction

23. WICID Output Planner

24. WICID Output Previewer

25. Some examples of data extraction: Query 1: Migrants from Greece to GB by age

26. Age profile of migrants from Greece, 1990-91 Source: 1991 Census Crown Copyright: ESRC/JISC Purchase

27. Query 2: Migrants to districts in GB from Greece, 1990-91

28. Districts receiving most migrants from Greece, 1990-91 Source: 1991 Census Crown Copyright: ESRC/JISC Purchase

29. Social structure of Leeds and surrounding districts using 1991 SWS

30. Query: Journey to work flows between zones by social class, 1991

31. Social class structure of commuters in Leeds and between Leeds and surrounding districts, 1991 Source: 1991 Census Crown Copyright: ESRC/JISC Purchase

32. Source: 1991 Census Crown Copyright: ESRC/JISC Purchase Proportions of commuters to Central Leeds from other wards and surrounding districts by social class, 1991 Professional Managerial and Technical

33. Source: 1991 Census Crown Copyright: ESRC/JISC Purchase Skilled Non-manual Skilled Manual

34. Source: 1991 Census Crown Copyright: ESRC/JISC Purchase Partly Skilled Unskilled

35. Conclusions/Next steps §CIDS now up and running §Flexible metadata structure of WICID will allow 2001 Census results to be included in the system §WICID will be used to verify the 2001 data in 2003 §Mapping option for geographical area selection now being developed §Analysis and modelling facilities intended but raises difficult questions