Overconfidence effect

The overconfidence effect is a well-established bias in which a person's subjective confidence in their judgments is reliably greater than the objective accuracy of those judgments, especially when confidence is relatively high.[1][2] Overconfidence is one example of a miscalibration of subjective probabilities. Throughout the research literature, overconfidence has been defined in three distinct ways: (1) overestimation of one's actual performance; (2) overplacement of one's performance relative to others; and (3) overprecision in expressing unwarranted certainty in the accuracy of one's beliefs.[3][4]

The most common way in which overconfidence has been studied is by asking people how confident they are of specific beliefs they hold or answers they provide. The data show that confidence systematically exceeds accuracy, implying people are more sure that they are correct than they deserve to be. If human confidence had perfect calibration, judgments with 100% confidence would be correct 100% of the time, 90% confidence correct 90% of the time, and so on for the other levels of confidence. By contrast, the key finding is that confidence exceeds accuracy so long as the subject is answering hard questions about an unfamiliar topic. For example, in a spelling task, subjects were correct about 80% of the time, whereas they claimed to be 100% certain.[5] Put another way, the error rate was 20% when subjects expected it to be 0%. In a series where subjects made true-or-false responses to general knowledge statements, they were overconfident at all levels. When they were 100% certain of their answer to a question, they were wrong 20% of the time.[6]

  1. ^ Pallier, Gerry; Wilkinson, Rebecca; Danthiir, Vanessa; Kleitman, Sabina; Knezevic, Goran; Stankov, Lazar; Roberts, Richard D. (2002). "The Role of Individual Differences in the Accuracy of Confidence Judgments". The Journal of General Psychology. 129 (3): 257–299. doi:10.1080/00221300209602099. PMID 12224810. S2CID 6652634.
  2. ^ Moore, Don A.; Healy, Paul J. (April 2008). "The trouble with overconfidence". Psychological Review. 115 (2): 502–517. doi:10.1037/0033-295X.115.2.502. ISSN 1939-1471. PMID 18426301.
  3. ^ Moore, Don A.; Healy, Paul J. (2008). "The trouble with overconfidence". Psychological Review. 115 (2): 502–517. CiteSeerX 10.1.1.335.2777. doi:10.1037/0033-295X.115.2.502. PMID 18426301. Archived from the original on 2014-11-06.
  4. ^ Moore, Don A.; Schatz, Derek (August 2017). "The three faces of overconfidence". Social and Personality Psychology Compass. 11 (8): e12331. doi:10.1111/spc3.12331. ISSN 1751-9004.
  5. ^ Adams, P. A.; Adams, J. K. (1960). "Confidence in the recognition and reproduction of words difficult to spell". The American Journal of Psychology. 73 (4): 544–552. doi:10.2307/1419942. JSTOR 1419942. PMID 13681411.
  6. ^ Lichtenstein, Sarah; Fischhoff, Baruch; Phillips, Lawrence D. (1982). "Calibration of probabilities: The state of the art to 1980". In Kahneman, Daniel; Slovic, Paul; Tversky, Amos (eds.). Judgment Under Uncertainty: Heuristics and Biases. Cambridge University Press. pp. 306–334. ISBN 978-0-521-28414-1.