Motivational and performance consequences of over-estimating exam performance: notable differences by gender and ethnicity

A well-known finding from popular psychology is the Dunning-Kruger effect – the tendency of low-performers to overestimate their own performance and high performers to underestimate their own performance. In much of the literature on this effect, it is taken as a given that more accurate self-assessments of performance are crucial for not just the success of individuals, but for the success of industries like education and healthcare. Yet, we have not found a study that directly measured differences in outcomes that were correlated with inaccurately estimating one's performance. In the present study, we investigate changes in physics knowledge and physics motivational beliefs that are correlated with overestimating one's performance on physics exams. We find that students who overestimate their exam performance do not see any gains in physics knowledge over the course of a semester, compared with a 0.30 standard deviation increase for students who do not overestimate their performance. In addition, we find that students who overestimate their performance see increases in test anxiety, increased interest in physics, and increased stereotype threat. When we further examine these changes for different demographic groups, we find that women who overestimate their own exam performance are able to self-correct and perform just as well as women who underestimate their performance on the post-test physics knowledge assessment. We further find that ethnic and racial minority students who underestimate their performance see large decreases in test anxiety and stereotype threat, whereas these minoritized students who overestimate their performances see increases on these metrics. In sum, the results suggest that an inability to accurately assess one's own performance may have negative impacts on both learning and motivational beliefs in physics.