Choosing colors for map display icons using models of visual search.

Objective: We show how to choose colors for icons on maps to minimize search time using predictions of a model of visual search. Background: The model analyzes digital images of a search target (an icon on a map) and a search display (the map containing the icon) and predicts search time as a function of target-distractor color distinctiveness and target eccentricity. Method: We parameterized the model using data from a visual search task and performed a series of optimization tasks to test the model's ability to choose colors for icons to minimize search time across icons. Map display designs made by this procedure were tested experimentally. In a follow-up experiment, we examined the model's flexibility to assign colors in novel search situations. Results: The model fits human performance, performs well on the optimization tasks, and can choose colors for icons on maps with novel stimuli to minimize search time without requiring additional model parameter fitting. Conclusion: Models of visual search can suggest color choices that produce search time reductions for display icons. Application: Designers should consider constructing visual search models as a low-cost method of evaluating color assignments.