Research Team: R. Maheswaran, R. Haining, S. Wise, P. Brindley, P. Fryers.
Funding: Trent regional Health Authority.
Abstract
The development of Geographic Information Systems (GIS) has been assisted by the recent expansion in the availability of digital data. However, this has also highlighted a number of problems including technical issues associated with incompatible zonal systems. The issue arises when data values for one zoning system are required for another, but the boundaries of the datasets do not align. The well-documented solution is areal interpolation, whereby data from existing source zones are re-estimated for the required target units. However, there are numerous methods of areal interpolation each with their own assumptions which directly affect estimates. This aspect of the wider project examining the relationship between air quality and hospital admissions and mortality for respiratory conditions examines the different ways of attaching grid air quality data to enumeration districts.
Illustrations:
Figure 1 : The data utilised within the project.
Figure 2: The results of varying methods of areal interpolation.
Further reading:
- Brindley P., S. W., P. Fryers, R. Maheswaran, and R. Haining (2001). An empirical study to assess the accuracy of simple areal interpolation methods. AGILE conference on GIS, Brno.
- Sheffield Centre for Geographic Information and Spatial Analysis
- The University of Sheffield – Public Health GIS Unit