Abstract

Two experiments were performed for the purpose of identifying the differences between inferences of ability and of effort in adults. In experiment 1. subjects were given the single information about target person's performance or ability or effort, and were asked to infer the degree of target's effort and ability and to predict target's performance. One-third of the subjects in experiment 2 were given the combined information about ability and effort, and were asked to predict target's performance. The other two groups of subjects were given the combined information about one cause(i.e., ability, effort) and effect(i.e., performance), and were asked to infer the degree of the other cause(i.e., effort, ability). The results were as follows : (1) When the target's ability or effort was high, subjects discounted the degree of effort more than that of ability regardless of performance information. (2) Subjects, as a whole, predicted more degree of performance under high ability condition than under high effort condition. (3) Finally, on subjects' true-false judgments about ability-effort relations, it appeared that people believed that effort is both directly and inversely proportional to ability, but ability is only directly proportional to effort. Based on the above differences, it was discussed that as a cause of performance, ability is distinct from effort in some respects.