McNabb, LiamLaramee, Robert S.Wilson, Max{Tam, Gary K. L. and Vidal, Franck2018-09-192018-09-192018978-3-03868-071-0https://diglib.eg.org:443/handle/10.2312/cgvc20181221https://doi.org/10.2312/cgvc.20181221Choropleth maps are an invaluable visualization type for mapping geo-spatial data. One advantage to a choropleth map over other geospatial visualizations such as cartograms is the familiarity of a non-distorted landmass. However, this causes challenges when an area becomes too small in order to accurately perceive the underlying color. When does size matter in a choropleth map? We conduct an experiment to verify the relationship between choropleth maps, their underlying color map, and a user's perceivability. We do this by testing a user's perception of color relative to an administrative area's size within a choropleth map, as well as user-preference of fixed-locale maps with enforced minimum areas. Based on this initial experiment we can make the first recommendations with respect to a unit area's minimum size in order to be perceivably useful.Humancentered computingUser studiesGeographic visualizationInformation visualizationComputing methodologiesVisibilityPerception10.2312/cgvc.20181221163-171