Research Article Overconfidence in an Objective Anticipatory Motor Task

ABSTRACT—Overconfidence can place humans in hazard-ous situations, and yet it has been observed in a variety of cognitive tasks in which participants have to rate their own performance.We demonstrate here that overconfidence can be revealed in a natural and objective visuo-motor task. Participants were asked to press a key in synchrony with a predictable visual event and were rewarded if they suc-ceeded and sometimes penalized if they were too quick or too slow. If they had used their own motor uncertainty in anticipating the timing of the visual stimulus, they would have maximized their gain. However, they instead dis-played an overconfidence in the sense that they underesti-mated the magnitude of their uncertainty and the cost of their error. Therefore, overconfidence is not limited to subjective ratings in cognitive tasks, but rather appears to be a general characteristic of human decision making. Overconfidence refers to the human tendency to overestimate one’s own abilities and knowledge (Alpert & Raiffa, 1982; Osk-amp, 1965). Overconfidence is believed to have dramatic con-sequences in such diversified areas as warfare (Johnson et al., 2006), stock-exchange trading (Statman, Thorley, & Vorkink, 2006), and driving (Svenson, 1981). One methodological diffi-culty that has hampered research in this field, to the point that the very existence of overconfidence has been challenged (Ayton &amp