Debunking the Dunning-Kruger Effect

It might be time to debunk the Dunning-Kruger effect.

For those who may not be familiar, in the 1990s Cornell University professors David Dunning and Justin Kruger conducted a now-famous experiment to test whether incompetent people were unaware of their incompetence. In the study, the lowest-scoring participants estimated they did better than 62% of everyone else, while the highest-scoring participants thought they scored better than 68%. As the researchers wrote, the least-skilled were both “unskilled and unaware.”

In the years after this initial study, many other researchers validated the effect and it was supported by other learning models like “unconsciously incompetent.” The Dunning-Kruger effect became so accepted that the arrogant fool became a stereotype in books and movies.

However, the Dunning-Kruger effect might have been debunked. Through a series of experiments, researchers have recently demonstrated the effect is an artifact of the research design, and not a flaw in how the brain processes information.

To prove this, they designed an experiment using random data and fictional test-takers. The results showed the fictional test-takers with the worst scores overestimated their performance the most, just like real humans did in other experiments. This is because the fictional test-takers had results which were the furthest from a perfect score.

In a follow-up study with real humans, only 16.5% of those who scored in the bottom quartile significantly overestimated their abilities; in fact, 3.9% significantly underestimated their score. In other words, 80% of unskilled participants were good at estimating their real ability – “a far cry from the idea put forth by Dunning and Kruger that the unskilled consistently overestimate their skills”.

While this research shows people do have an innate ability to gauge their competence and knowledge, it didn’t debunk the entire Dunning-Kruger effect. Most of the participants reported they were better than the other participants; the illusory superiority effect.

Like the children in Lake Woebegone, everyone thinks they are above average.