People are often faced with decisions involving uncertain outcomes. Rather than making judgments in accord with probability theory, past research suggests that people use a limited number of heuristics. There has been little research, however, on the process by which heuristics are selected. This proposal for a Research Planning Grant examines the question of when each heuristic is used. The principal investigator proposes that people have multiple heuristics, but that one occupies a default position. The plan is to development an experimental methodology for measuring heuristic use in probability judgment. This methodology will be used to examine factors which influence heuristic selection. The project will identify conditions which can improve the accuracy of probability estimation and enhance the quality of decisions involving uncertainty.
