You think you're so good

You think you're so good

What is the Dunning Kruger Effect?

Have you ever known a person who was so bad at something, he didn’t know he was bad? We’ve all seen it: on average, car drivers rate themselves as above average. The busker belts out their song oblivious to the depth of their awfulness.

In a  test, those who scored near the bottom  rated their abilities near the top third.

In a test, those who scored near the bottom rated their abilities near the top third.Credit:Rob Young

Clearly that can’t be right, so David Dunning and Justin Kruger from Cornell University did some research to see if it could be backed up by scientific evidence.

They gave students a grammar test then asked them to estimate how well they scored. Those who scored near the bottom (the 10th percentile) rated their own abilities at towards the top third (the 67th percentile).
In another experiment they asked people to rate how funny different jokes were and, as with the grammar test, those who performed worst grossly overestimated their abilities.


For their report, Unskilled and Unaware of It, Dunning and Kruger were awarded the 2001 Ig Nobel Prize for psychology. It is recognition for applying science to something that has long been observed by others. As my mother says, lack of knowledge is no bar to expertise, and Nietzsche wrote, “Convictions are more dangerous enemies of truth than lies.”

We can feel smug about this, but we all do it at various times. We each can be prone to unconscious incompetence, and therein lies a clue of what to do about it. The answer, of course, is honest self-appraisal.
On that note, I wanted to write that narcissism was likely to be a predictor of this effect because a narcissist is prone to inflated self-assessment, but I found mixed results in the research.

Refinements to this idea are now bringing in greater nuance, such as whether the skill being attempted is easy or difficult. It also matters whether performance has a simple measure such as in a game, because it’s harder to dodge a dodgy score.

Curiously, it’s not just low achievers who misjudge their performance. High achievers are also prone, but in the opposite direction by underrating themselves. That leads to another cognitive bias, “Impostor Syndrome”, which was first described by Pauline Clance and Suzanne Imes in 1978.

For these people, nothing they do is ever good enough, and if they do get recognition, it’s because nobody noticed.

Response: Rod Taylor, Fuzzy Logic

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