GISCIENCE: Addressing Aggregation and Uncertainty

Uncertainty is inevitably embedded in geographic data. While uncertainty can occur in locations and attributes, attribute uncertainty is a concern more frequently than location uncertainty in human geography research. Socio-economic phenomena are often measured based on areal units and utilized in geographic research using GIS and statistical methods, where sampling, measurement, and specification errors are commonly embedded. Because uncertainty in socio-economic variables can result in unreliable results, it is crucial to recognize uncertainty in geographic data, to understand propagation of uncertainty in data processing, and to incorporate uncertainty into data analysis and modeling properly. This chapter discusses uncertainty in data, specifically census data, first and then recent developments in uncertainty visualization, spatial pattern measurement with uncertainty, and uncertainty issues in spatial analysis and modeling.