An unlucky feeling: Overconfidence and noisy feedback

How do individuals’ beliefs respond to ego-relevant information? After receiving noisy, but unbiased performance feedback, participants in an experiment overestimate their own scores on a quiz and believe their feedback to be ‘unlucky’, estimating that it under-represents their score by 13%. However, they exhibit no such overconfidence in non-ego-relevant beliefs—in this case, estimates of others’ scores. Comparing subjects’ belief-updating to the Bayesian benchmark, we find that this ‘unlucky feeling’ is largely due to overconfident priors, with biased updating driving overconfidence only among the participants with the worst-calibrated beliefs. This suggests that social comparisons contribute to the biased response to feedback on relative performance observed in other studies. While feedback improves performance estimates, this learning does not translate into improved estimates of subsequent performances. This suggests that beliefs about ability are updated differently than beliefs about a particular performance, contributing to the persistence of overconfidence.

► How does overconfidence about absolute performance arise and persist after feedback?
► Participants overestimate their own scores on a quiz and believe their feedback to be ‘unlucky’.
► They exhibit no such overconfidence in (non-ego-relevant) estimates of others’ scores.
► Most of this overestimation is not explained by deviations from Bayesian updating.
► Feedback improves performance estimates, but this does not help estimates of later performances.