The performance heuristic: a misguided reliance on past success when predicting prospects for improvement.

In estimating whether they are likely to improve on a performance task, people lean on a performance heuristic. That is, people rely on their previous performance success as a positive cue when estimating their prospects for performance improvement. Participants whose initial performance was better--either at a darts game (Study 1) or an anagram task (Study 2)-bet more money (Study 1) or estimated a higher subjective likelihood (Study 2) that their subsequent performance would show a specified amount of improvement. Reliance on the heuristic was unwise, for initial performance did not positively predict (and, in fact, negatively predicted) performance improvement. Study 2 suggests that the performance heuristic emerges because forecasters engage in attribute substitution, naturally focusing on their demonstrated performance instead of whether they have already maxed out their potential for improvement on the task. Self-assessments of their initial performance mediated the performance heuristic, but focusing participants on how much performance potential lay before them disrupted it (Study 2). Study 3 showed that the performance heuristic is a general-purpose heuristic that is used not merely to predict one's own prospects for improvement, but the prospects for other improvement (e.g., mutual funds' rate of return) as well.