Symbolizing Quantitative Differences on Color CRTs

摘要

The study examined the use of brightness to encode ordinal differences between symbols on CRT screens. The symbols were either U.S. states on a choropleth map or simple rectangles. The effects of background color and brightness were also measured. These results were related to the conventional practice with printed maps. Subjects compared pairs of symbols with different brightnesses, displayed on three background colors each of which had three brightnesses, and chose as quickly as possible which of the pair of symbols indicated 'more.' On both the maps and the rectangles, subject responses indicated that the darker symbols meant 'more.' These CRT results are consistent with the convention used with printed maps. Keywords: Map design; Luminance contrast; Information display. (JES)