[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.
By contrast, the key finding is that confidence exceeds accuracy so long as the subject is answering hard questions about an unfamiliar topic.
This subsection of overconfidence focuses on the certainty one feels in their own ability, performance, level of control, or chance of success.
[8] The planning fallacy describes the tendency for people to overestimate their rate of work or to underestimate how long it will take them to get things done.
[10] This may be in part because people engage in more defensive pessimism in advance of important outcomes,[11] in an attempt to reduce the disappointment that follows overly optimistic predictions.
After making a series of item-confidence judgments, if people try to estimate the number of items they got right, they do not tend to systematically overestimate their scores.
The strongest evidence of overprecision comes from studies in which participants are asked to indicate how precise their knowledge is by specifying a 90% confidence interval around estimates of specific quantities.
[16] In fact, hit rates are often as low as 50%, suggesting people have drawn their confidence intervals too narrowly, implying that they think their knowledge is more accurate than it actually is.
[26] Although there is some evidence that optimistic beliefs are correlated with better life outcomes, most of the research documenting such links is vulnerable to the alternative explanation that their forecasts are accurate.
People tend to overestimate what they personally know, unconsciously assuming they know facts they would actually need to access by asking someone else or consulting a written work.
Social psychologist Scott Plous wrote, "No problem in judgment and decision making is more prevalent and more potentially catastrophic than overconfidence.
[32] If corporations and unions were prone to believe that they were stronger and more justified than the other side, that could contribute to their willingness to endure labor strikes.
Oskamp tested groups of clinical psychologists and psychology students on a multiple-choice task in which they drew conclusions from a case study.
Genuine expert intuition is acquired by learning from frequent, rapid, high-quality feedback about the quality of previous judgments.
Those who master a body of knowledge without learning from such expertise are called "respect experts" by Kahneman, Sibony, and Sunstein.
[42] Very high levels of core self-evaluations, a stable personality trait composed of locus of control, neuroticism, self-efficacy, and self-esteem,[43] may lead to the overconfidence effect.