Discriminating Strata in Scatterplots
通过行为实验比较散点图中不同符号类型（颜色、字母等）对地层区分速度和准确性的影响，发现颜色最优，且测量反应时对图形感知研究至关重要。
Abstract When multiple groups are shown in a scatterplot each stratum is represented by a different symbol; for example, three strata might be coded using red, green, and yellow circles. Various symbol types were compared by behavioral experiment: Subjects were fastest when strata were coded using different colors and slowest when strata were coded with confusable letters—but there were no differences in accuracy. Accuracy differed only when processing time was restricted, again with different colors and confusable letters representing the two extremes. We conclude that color is the optimal symbol type and show that measuring response latency in addition to accuracy is essential in research on graphical perception.