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

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GeoConvert Creating that Spatial
Relationship David RawnsleyMimas, University
of Manchester
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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.

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The Problem

• Many types of geography in the UK
• Administrative
• Electoral
• Postal
• Health
• European
• Census
• Statistical

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A Little UK Geography
Strategic Health Authorities - 2006
Parliamentary Constituencies 2005
Counties, Districts, Unitary Authorities - 1998
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Further Complication
UK
Wales
Scotland
England
Northern Ireland
Unitary Authority
GOR
Council Area
District Councils
UA
County
ST Electoral Division
ST Postcode Sector
CAS Postcode Sector
LLSOA
District
Ward
CAS Electoral Division
Intermediate Zones
ST Ward
MSOA
Data Zones
LSOA
CAS Ward
English and Welsh Output Areas
Scottish Output Areas
Northern Irish Output Areas
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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

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Problems With The NSPD

• Its huge 1.37 Gb at last count
• Its cumbersome flat file with many rows or
  basic Access database
• Horrible variable names OSHLTHAU
• It keeps changing
• Very little support from ONS
• Why cant someone tame it?

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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

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GeoConvert
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What Does It Actually Do?

• 3 functions
• Postcode related information
• Geography matching
• Geographical data conversion

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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

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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

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Isnt 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

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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
• http//geoconvert.mimas.ac.uk