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Dunning-Kruger Effect

In the field of psychology, the Dunning-Kruger Effect is a cognitive bias in which people with low ability at a task overestimate their ability. It is related to the cognitive bias of illusory superiority and comes from the inability of people to recognize their lack of ability. Without the self-awareness of metacognition, people cannot objectively evaluate their competence or incompetence.

As described by social psychologists David Dunning and Justin Kruger, the bias results from an internal illusion in people of low ability and from an external misperception in people of high ability; that is, the miscalibration of the incompetent stems from an error about the self, whereas the miscalibration of the highly competent stems from an error about others. Colloquially, people experiencing this bias are said to be at the top of "Mount Stupid," although this is not used in scientific articles about the Dunning-Kruger effect.

The psychological phenomenon of illusory superiority was identified as a form of cognitive bias in Kruger and Dunning's 1999 study, "Unskilled and Unaware of It: How Difficulties in Recognizing One's Own Incompetence Lead to Inflated Self-Assessments".The identification derived from the cognitive bias evident in the criminal case of McArthur Wheeler, who, on April 19, 1995, robbed two banks while his face was covered with lemon juice, which he believed would make it invisible to the surveillance cameras. This belief was based on his misunderstanding of the chemical properties of lemon juice as an invisible ink.

Other investigations of the phenomenon, such as "Why People Fail to Recognize Their Own Incompetence" (2003), indicate that much incorrect self-assessment of competence derives from the person's ignorance of a given activity's standards of performance. Dunning and Kruger's research also indicates that training in a task, such as solving a logic puzzle, increases people's ability to accurately evaluate how good they are at it.

In Self-insight: Roadblocks and Detours on the Path to Knowing Thyself (2005), Dunning described the Dunning-Kruger effect as "the anosognosia of everyday life", referring to a neurological condition in which a disabled person either denies or seems unaware of his or her disability. He stated: "If you're incompetent, you can't know you're incompetent ... The skills you need to produce a right answer are exactly the skills you need to recognize what a right answer is."

In 2011, Dunning wrote about his observations that people with substantial, measurable deficits in their knowledge or expertise, lack the ability to recognize those deficits and, therefore, despite potentially making error after error, tend to think they are performing competently when they are not: "In short, those who are incompetent, for lack of a better term, should have little insight into their incompetence—an assertion that has come to be known as the Dunning–Kruger effect". In 2014, Dunning and Helzer described how the Dunning–Kruger effect "suggests that poor performers are not in a position to recognize the shortcomings in their performance".

The Dunning-Krugger effect

Dunning and Kruger tested the hypotheses of the cognitive bias of illusory superiority on undergraduate students of introductory courses in psychology by examining the students' self-assessments of their intellectual skills in logical reasoning (inductive, deductive, abductive), English grammar, and personal sense of humor. After learning their self-assessment scores, the students were asked to estimate their ranks in the psychology class. The competent students underestimated their class rank, and the incompetent students overestimated theirs, but the incompetent students did not estimate their class rank as higher than the ranks estimated by the competent group. Across four studies, the research indicated that the study participants who scored in the bottom quartile on tests of their sense of humor, knowledge of grammar, and logical reasoning, overestimated their test performance and their abilities; despite test scores that placed them in the 12th percentile, the participants estimated they ranked in the 62nd percentile.

Moreover, competent students tended to underestimate their own competence, because they erroneously presumed that tasks easy for them to perform were also easy for other people to perform. Incompetent students improved their ability to estimate their class rank correctly after receiving minimal tutoring in the skills they previously lacked, regardless of any objective improvement gained in said skills of perception. The study "Mind-Reading and Metacognition: Narcissism, not Actual Competence, Predicts Self-estimated Ability" (2004) extended the cognitive-bias premise of illusory superiority to test subjects' emotional sensitivity toward other people and their own perceptions of other people.

The study "How Chronic Self-Views Influence (and Potentially Mislead) Estimates of Performance" (2003) indicated a shift in the participants' view of themselves when influenced by external cues. The participants' knowledge of geography was tested; some tests were intended to affect the participants' self-view positively and some were intended to affect it negatively. The participants then were asked to rate their performances; the participants given tests with a positive intent reported better performance than did the participants given tests with a negative intent.

To test Dunning and Kruger's hypotheses, "that people, at all performance levels, are equally poor at estimating their relative performance", the study "Skilled or Unskilled, but Still Unaware of It: How Perceptions of Difficulty Drive Miscalibration in Relative Comparisons" (2006) investigated three studies that manipulated the "perceived difficulty of the tasks, and, hence, [the] participants' beliefs about their relative standing". The investigation indicated that when the experimental subjects were presented with moderately difficult tasks, there was little variation among the best performers and the worst performers in their ability to predict their performance accurately. With more difficult tasks, the best performers were less accurate in predicting their performance than were the worst performers. Therefore, judges at all levels of skill are subject to similar degrees of error in the performance of tasks.

In testing alternative explanations for the cognitive bias of illusory superiority, the study "Why the Unskilled are Unaware: Further Explorations of (Absent) Self-insight Among the Incompetent" (2008), reached the same conclusions as previous studies of the Dunning–Kruger effect: that, in contrast to high performers, "poor performers do not learn from feedback suggesting a need to improve".

Individuals of relatively high social class are more overconfident than lower-class individuals

With thanks to Wikipedia and Scott Adams

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