Con®dence Judgments by Actors and Observers

We report three experiments comparing con®dence judgments made by actors and by observers. In Experiment 1, actors generated qualitative answers (countries of the world) in a country-identi®cation task; in Experiment 2, actors generated quantitative answers (years) in a historical event-dating task. Both actors and observers indicated their con®dence in the actors' answers. Actors were signi®cantly less con®dent in their answers than were observers in the ®rst experiment. This e€ect was substantially reduced in the second experiment, whether con®dence was measured by judged probability or by credible interval width. Experiment 3 used a control task in which actors attempted to bring an outcome variable into a desired range. In contrast to the ®rst two experiments, actors in the control task were more con®dent than observers. Because subjects were generally overcon®dent in all three experiments, the present results demonstrate that the use of observers can reduce or exacerbate overcon®dence depending on the kind of task and the nature of the event or possibility under evaluation. # 1997 by John Wiley & Sons, Ltd. Journal of Behavioral Decision Making, 10, 221±242 (1997) No. of Figures: 3 No. of Tables: 5 No. of References: 22