Incompetence
“Not only do they reach erroneous conclusions and make unfortunate choices, but their incompetence robs them of the ability to realize it,” wrote Kruger.
In a series of studies, Kruger and Dunning found that subjects who scored in the lowest quartile on tests of logic, English grammar and humor were also the most likely to “grossly overestimate” how well they had performed.
In all 3 tests, subjects’ ratings of their ability were positively linked to their actual scores. But the lowest-ranked participants showed much greater distortions in their self-estimates.
Asked to evaluate their performance on the test of logical reasoning, subjects who scored only in the 12th percentile guessed that they had scored in the 62nd percentile, and deemed their overall skill at logical reasoning to be at the 68th percentile.
Similarly, subjects who scored at the 10th percentile on the grammar test ranked themselves at the 67th percentile in the ability to “identify grammatically correct standard English,” and estimated their test scores to be at the 61st percentile.
On the humor test, in which participants were asked to rate jokes according to their funniness (subjects’ ratings were matched against those of an “expert” panel of professional comedians), low-scoring subjects were also more apt to have an inflated perception of their skill. But the results were less conclusive.
Unlike unskilled counterparts, the most able subjects in the study were likely to underestimate their competence.
When high-scoring subjects were asked to “grade” the grammar tests of their peers, however, they quickly revised their evaluations of their own performance. The self-assessments of those who scored badly themselves were unaffected by the experience of grading others; some subjects even further inflated their estimates of their own abilities.
A short training session in logical reasoning improved the ability of low-scoring subjects to assess their performance realistically.
Other studies have found that the vast majority of people rate themselves as “above average” on a wide array of abilities. And this overestimation is more likely for tasks that are difficult than for those that are easy.
“Incompetent People Really Have No Clue, Studies Find They’re blind to own failings, others’ skills,” by Erica Goode