Geographic information systems and the spatial dimensions of American politics

In research on American politics, the use of geographic information systems (GIS) is most often thought of in connection with redistricting and the study of election results. In the past ten years, political scientists have realized that GIS can help them address many research questions and data analysis tasks quite apart from these traditional applications. These include the analysis of point patterns and the detection of clustering; the study of diffusion of influence; and the measurement of spatial relationships involving key constructs such as proximity and distance, flow, and interaction. GIS tools also prove to be the exploratory complements to the suite of tools being used in spatial econometrics to test explicit hypotheses about the impact of geography and spatial arrangement on political outcomes.