Dunning-Krueger Effect

From Wikipedia, the free encyclopedia

The Dunning–Kruger effect is a cognitive bias in which "people reach erroneous conclusions and make unfortunate choices but their incompetence robs them of the metacognitive ability to realize it."[1] The unskilled therefore suffer from illusory superiority, rating their own ability as above average, much higher than it actually is, while the highly skilled underrate their abilities, suffering from illusory inferiority. This leads to the perverse situation in which less competent people rate their own ability higher than more competent people. It also explains why actual competence may weaken self-confidence: because competent individuals falsely assume that others have an equivalent understanding. "Thus, 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." “In the modern world the stupid are cocksure while the intelligent are full of doubt.”

The phenomenon was demonstrated in a series of experiments performed by Justin Kruger and David Dunning, then both of Cornell University. However, the phenomenon had been assumed by many philosophers for nearly a century prior to Kruger and Dunning's study.

Kruger and Dunning noted a number of previous studies which tend to suggest that in skills as diverse as reading comprehension, operating a motor vehicle, and playing chess or tennis, "ignorance more frequently begets confidence than does knowledge" (as Charles Darwin put it). They hypothesized that with a typical skill which humans may possess in greater or lesser degree: Incompetent individuals tend to overestimate their own level of skill. Incompetent individuals fail to recognize genuine skill in others. Incompetent individuals fail to recognize the extremity of their inadequacy. If they can be trained to substantially improve their own skill level, these individuals can recognize and acknowledge their own previous lack of skill. The authors draw an analogy with anosognosia—a condition in which a person who suffers a physical disability due to brain injury seems unaware of or denies the existence of the disability. This may include unawareness of quite dramatic impairments, such as blindness or paralysis.

Kruger and Dunning set out to test these hypotheses on human subjects consisting of Cornell undergraduates who were registered in various psychology courses. In a series of studies, they examined self-assessment of logical reasoning skills, grammatical skills, and humor. After being shown their test scores, the subjects were again asked to estimate their own rank, whereupon the competent group accurately estimated their rank, while the incompetent group still overestimated their own rank. As Dunning and Kruger noted, Across four studies, the authors found that participants scoring in the bottom quartile on tests of humor, grammar, and logic grossly overestimated their test performance and ability. Although test scores put them in the 12th percentile, they estimated themselves to be in the 62nd. Meanwhile, people with true knowledge tended to underestimate their competence. Roughly, participants who found tasks to be relatively easy erroneously assumed, to some extent, that the tasks must also be easy for others. A follow-up study suggests that grossly incompetent students improve both their skill level and their ability to estimate their class rank only after extensive tutoring in the skills they had previously lacked. They won Ig Nobel Prizes in Psychology in 2000 with their report, "Unskilled and Unaware of It: How Difficulties in Recognizing One's Own Incompetence Lead to Inflated Self-Assessments". In 2003 Dunning and Joyce Ehrlinger, also of Cornell University, published a study that detailed a shift in people's views of themselves influenced by external cues. Participants in the study (Cornell University undergraduates) were given tests of their knowledge of geography, some intended to positively affect their self-views, some intended to affect them negatively. They were then asked to rate their performance, and those given the positive tests reported significantly better performance than those given the negative. Daniel Ames and Lara Kammrath extended this work to sensitivity to others, and the subjects' perception of how sensitive they were. Work by Burson Larrick and Joshua Klayman has suggested that the effect is not so obvious and may be due to noise and bias levels. Dunning, Kruger, and coauthors' latest paper on this subject comes to qualitatively similar conclusions after making some attempt to test alternative explanations.

^ a b c Kruger, Justin; David Dunning (1999). "Unskilled and Unaware of It: How Difficulties in Recognizing One's Own Incompetence Lead to Inflated Self-Assessments". Journal of Personality and Social Psychology 77 (6): 1121–34. doi:10.1037/0022-3514.77.6.1121. PMID 10626367. ^ Bertrand Russell, The Triumph of Stupidity (1933-05-10) in Mortals and Others: Bertrand Russell's American Essays, 1931-1935 (Routledge, 1998, ISBN 0-415-17866-5), p. 28 ^ http://en.wikiquote.org/wiki/Bertrand_Russell#Sourced ^ Dunning, David; Kerri Johnson, Joyce Ehrlinger and Justin Kruger (2003). "Why people fail to recognize their own incompetence". Current Directions in Psychological Science 12 (3): 83–87. doi:10.1111/1467-8721.01235. ^ Charles Darwin (1871). "The Descent of Man" (w). pp. Introduction, page 4. Retrieved 2008-07-18. ^ Joyce Ehrlinger; David Dunning (January 2003). "How Chronic Self-Views Influence (and Potentially Mislead) Estimates of Performance". Journal of Personality and Social Psychology (American Psychological Association) 84 (1): 5–17. doi:10.1037/0022-3514.84.1.5. ^ Daniel R. Ames; Lara K. Kammrath (September 2004). "Mind-Reading and Metacognition: Narcissism, not Actual Competence, Predicts Self-Estimated Ability". Journal of Nonverbal Behavior (Springer Netherlands) 28 (3): 187–209. doi:10.1023/B:JONB.0000039649.20015.0e. ^ Burson, K.; Larrick, R.; Klayman, J. (2006). "Skilled or unskilled, but still unaware of it: how perceptions of difficulty drive miscalibration in relative comparisons". Journal of personality and social psychology 90 (1): 60–77. doi:10.1037/0022-3514.90.1.60. PMID 16448310. edit ^ Ehrlinger, Joyce; Johnson, Kerri; Banner, Matthew; Dunning, David; Kruger, Justin (2008). "Why the unskilled are unaware: Further explorations of (absent) self-insight among the incompetent" (PDF). Organizational Behavior and Human Decision Processes (105): 98–121.