Decision Fluency and Overconfidence Among Beginners

We investigated the development of overconfidence among beginners completing a multicue probabilistic learning task. Beginners did not start out as overconfident in their judgments, but they rapidly surged to a "beginner's bubble" of overconfidence within just a few trials of experience. This bubble was associated, in part, to increased decision fluency as assessed via decision times. Initially participants were slow to reach decisions, but they sped up rapidly. This naturally occurring pattern predicted their rapidly rising confidence, which was not accompanied by a comparable increase in accuracy. In short, natural changes in decision fluency predicted confidence much more than they served as indicators of accuracy. After a pause, beginner confidence began to rise again as participants stopped spending as much time making decisions or looking at feedback after error, presumably shifting from a "learning" to a "performing" mindset, again reaching decisions with more speed.