GeoConvert: Creating that Spatial Relationship David Rawnsley Mimas, University of Manchester

Overview GeoConvert is an online geography matching and conversion tool for UK academics. GeoConvert allows registered users to obtain and manipulate complex geographical and postcode data in a straightforward way. A solution to a specific UK problem but it can be applied to any country.

The Problem Many types of geography in the UK  Administrative  Electoral  Postal  Health  European  Census  Statistical

A Little UK Geography Counties, Districts, Unitary Authorities Strategic Health Authorities Parliamentary Constituencies 2005

Further Complication WalesScotland England UA ST Ward CAS Ward Ward Unitary Authority ST Electoral Division CAS Postcode Sector MSOA LSOA LLSOA Intermediate Zones English and Welsh Output Areas Scottish Output Areas Northern Irish Output Areas GOR District County Council Area Data Zones District Councils CAS Electoral Division Northern Ireland UK ST Postcode Sector

A Partial Solution The NSPD  Produced by the Office for National Statistics  A long list of UK Postcodes  Also has other geographical zones  Postcode metadata  New version every quarter

Problems With The NSPD  It’s huge – 1.37 Gb at last count  It’s cumbersome – flat file with many rows or basic Access databaseflat file with many rowsbasic Access database  Horrible variable names – ‘OSHLTHAU’  It keeps changing  Very little support from ONS Why can’t someone tame it?

Our Hero At Last What is it?  Online web based access to NSPD  Range of functions  Provides a framework for integrating data  Regularly updated  Help and support provided FAQs Original documentation Glossary User Guides

GeoConvert

What Does It Actually Do? 3 functions  Postcode related information  Geography matching  Geographical data conversion

Why Should I Use It?  Prizes!  It enables datasets to be linked much more easily  It enables researchers to link their own data to many more datasets  It enables data to be linked historically  It allows users to quickly and easily get access to widely used deprivation and classification data

How Does It Do It? Postcode information direct from NSPD Use postcodes as a population proxy Dissection and re-aggregation of filtered postcodes between zones to achieve measure of proportional distribution of population Lots of complicated database stuff Lots of complicated interface stuff UK specific but the solution can be applied to any country

Isn’t Some Of That A Bit Dodgy? Dependent on accuracy of ‘how much?’ and ‘where?’ Boundary fuzziness due to unique allocation of postcodes Ideal data is population related with homogenous distribution male, female = good clusters of cancer patients = bad Based on current population current to historical works best Partial input = partial output

What Might It Do Next? A better population proxy? Different population proxies More metadata Confidence measures Standards based XML output Integration with external data sources Machine to machine Pipetastic