Regional Portrayal With Multi-Pattern Color Dot Maps

Abstract

Methods of portraying multiple distributions in the same map space are limited to a few, largely untested symbolization techniques. This paper investigates one of those techniques, the multi-pattern color dot map. A perception test is employed comparing the relative effectiveness of the multi-pattern map to single distribution dot maps in conveying'regional distribution information to map readers. Responses are analyzed with two measures: the consistency with which subjects defined region boundaries within the map; and the internal accuracy of regions identified. Results suggest that color dot maps are at least as effective as several single black and white dot maps in portraying regions.