On April 19, 1995 two Pittsburgh Banks were robbed in broad daylight. The robber wore no mask and surveillance camera clearly showed him holding a gun to the teller. Obviously, the police became sure about the suspect by watching the video tape. Later that night, the police arrested the suspect McArthur Wheeler. When they showed him the surveillance tapes, Wheeler stared in disbelief. “But I wore the juice,” he mumbled. He believed that if he rubbed his face with lemon juice he would be invisible to security cameras. Wheeler was neither crazy nor using any narcotic drugs. He just did incredible mistake with limited knowledge.
Such incident caught the eyes of the psychologist David Dunning and did some research with Justin Kruger regarding such phenomena. Then the term “Dunning Kruger Effect” emerged. The concept of the Dunning-Kruger effect is based on a 1999 journal published by psychologists David Dunning and Justin Kruger. They tested participants on their logic, grammar and sense of humor, and found that those who performed below average thought they could perform far beyond the average. Dunning-Kruger effect is a cognitive bias in which people wrongly overestimate their knowledge or ability in a specific area. The researchers attributed the trend to a problem of metacognition-the ability to analyze one’s own thoughts or performance. Dunning and Kruger wrote– ‘the individuals with limited knowledge suffer a dual burden; they not only reach mistaken conclusions and make regrettable errors, but their incompetence rob them of the ability to realize it.’