Learning to Adapt Evidence Thresholds in Decision Making

A basic challenge in decision-making is to know how long to search for information, and how to adapt search processes as performance, goals, and the nature of the task environment vary. We consider human performance on two experiments involving a sequence of simple multiple-cue decision-making trials, which allow search to be measured, and provide feedback on decision accuracy. In both experiments, the nature of the trials changes, unannounced, several times. Initially minimal search is required, then more extensive search is required, and finally only minimal search is again required to achieve decision accuracy. We find that people, considered both on aggregate, and as individuals, are sensitive to all of these changes. We discuss the theoretical implications of these findings for modeling search and decision-making, and emphasize that they show adaptation to an external error signal must be accompanied by some sort of internal self-regulation in any satisfactory account of people’s behavior.