Dunning-Kruger Effect

In Study 2 of Kruger and Dunning’s original article (Kruger and Dunning 1999), the authors gave college students a twenty-item test of logical reasoning with questions drawn from the Law School Admissions Test.

After completing the test, each student was asked to rate their performance relative to others on a percentile scale and also to predict the number of items they got correct. In presenting the results, Kruger and Dunning grouped the participants into quartiles (e.g., lowest 25 percent of scorers, next 25 percent of scorers, etc.). The classic finding is shown in Figure 1, a hypothetical graph that I created on my computer. People who scored low relative to other people greatly overestimated how well they did. Conversely, the people who scored in the top quartile slightly underestimated their performance. This kind of finding has been replicated many times by researchers in different laboratories with tests on a variety of subjects.

This coincides perfectly with the goal-setting literature, one of my major interests in my fifty years in higher academe. Basically, high performers tend to underestimate their performance, i.e., they have higher self-set goals or expectations of/for themselves, while lower performers over-estimate their performance, i.e., they have lower expectations and higher self-esteem.