The question
When two advisors have made the same underlying calls, does the one who states them with more confidence look more competent?
The method
In three experiments, college students studied two fictional financial advisors’ stock-direction judgments paired with the actual outcomes, then said which advisor they’d hire — one advisor (“moderate”) was reasonably well-calibrated, the other (“extreme”) was overconfident but built to have identical discrimination and identical categorical correctness (both were right 75% of the time in Experiment 3) [1].
The findings
Participants preferred the overconfident advisor in all three experiments — 71% in Experiment 1 [1], 64% in Experiment 2 [1], 63% in Experiment 3 [1] — even though the two advisors’ actual accuracy was held equal by design. Experiment 2 showed this tracked a belief about knowledge: participants who preferred the extreme advisor mostly rated him more knowledgeable, with no matching pattern for who was “more honest” [1]. Experiment 3 pinned down the mechanism directly: participants overestimated the confident advisor’s percentage of correct calls and underestimated the moderate advisor’s, even though both were correct exactly 75% of the time [1] — the authors call this the confidence heuristic, and present a quantitative model in which each point of perceived confidence gap buys the more confident advisor roughly 0.21 points of assumed correctness advantage [1]. A secondary result: participants high in both need for cognition and right-wing authoritarianism were most likely to prefer the extreme advisor (86% vs. 54% for everyone else) [1].
The limits
This is a lab paradigm with fictional advisors and no personal stakes beyond course credit and a small bonus; the paper doesn’t test whether the effect survives repeated real-world feedback over many more trials, and the authors themselves note 48 trials may be too few for genuine calibration-learning to set in [1].