A Measure of Similarity for Cellular Maps

Abstract

This research examines the KHAT coefficient of agreement as a means to compare map patterns stored in cellular data structures. The KHAT measure, used in psychology and remote sensing, is applicable to cartographic products and could provide a valuable service to users of Geographic Information Systems. In an experiment to test the utility of KHAT, subjects were asked to rank simple cell-based displays in terms of their similarity to a referent. Subjects' opinions were then compared to the similarity ratings provided by the KHAT measure. The results indicate that for map pairs agreeing at levels greater than chance, the KHAT coefficient is an excellent predictor of the visual impressions of map readers.