The Sunday Magazine

How ignorance makes us cocky

It's called the Dunning-Kruger Effect. When social psychologists David Dunning and Justin Kruger first wrote about it in 1999, it wasn't taken seriously. Now it's seen as a phenomenon that is having a very real impact on world events, from the 2008 financial crisis to the election of Donald Trump. Dunning, a professor of psychology at the University of Michigan, elaborates on his research.

Why people who know the least about a given topic are as confident as actual experts

Psychological research showed that many students who did poorly on a test assumed their grade would be higher than that of their classmates. (Frederick Florin/AFP/Getty Images)

Originally published February 15, 2019.

David Dunning is a professor of psychology at the University of Michigan, with a special focus on social psychology, cognition and decision making. (Submitted by David Dunning)

When social psychologists David Dunning and Justin Kruger first introduced the Dunning-Kruger Effect in 1999, their work didn't exactly set the world of psychological research ablaze with interest.

The Dunning-Kruger Effect is described as a cognitive quirk in which people with the least amount of knowledge or skill in a given field are as confident as those with the most expertise. At the time, it was treated largely as a curiosity, but not as terribly consequential research.

Twenty years later, the Dunning-Kruger Effect has been used to make sense of all manner of egregious errors in judgment, some with disastrous consequences, such as the sub-prime mortgage meltdown and financial crisis of 2008, or the Iraq War.

It's been cited as an explanation of why a majority of people believe they have above-average intelligence (a phenomenon long known to psychology, but a statistical impossibility) and why McArthur Wheeler, a notoriously incompetent bank robber, was convinced he could foil security cameras by rubbing lemon juice on his face. (He was arrested shortly after security cameras did, indeed, capture a clear image of his face during a robbery.)

The Dunning-Kruger Effect hinges on the fact that many people simply don't know what they don't know, even in areas where they're completely out of their depth.

Sooner or later, it's a phenomenon that's going to hit all of us.- David Dunning, psychologist

"You need expertise to be able to recognize lack of expertise accurately," Dunning told The Sunday Edition host Michael Enright.

"So those who lack expertise lack the knowledge to know that they're lacking [expertise]."

Dunning cautions against anyone feeling smug when they hear about spectacular examples of the Dunning-Kruger Effect.

"The key to this phenomenon is that this is one that visits all of us. All of us are vulnerable sooner or later somewhere to the Dunning-Kruger Effect," he said.

"Some people may be more immune to it than others, and some people, when they fall prey to the Dunning-Kruger Effect, might be more flamboyant than others. But sooner or later, it's a phenomenon that's going to hit all of us. It is just a part of the human condition."

As part of their research, Dunning and Kruger had university students assess how they performed on tests relative to their peers. They found not only that most students thought they did above average, but that students who were among the worst performers on the tests also tended to be highly confident that they were near the top of their class.

Their research has also found that the phenomenon results more from misinformation and misbelief rather than being uninformed.

"About a third of Americans, it's been shown, believe they know as much about vaccines and vaccination as experts and scientists. And it turns out that people who claim equal knowledge [to experts and scientists] tend to do the worst on actual tests of actual knowledge," Dunning said. 

The professor admits to being a little puzzled by the surge in interest in the Dunning-Kruger Effect of late. It could stem in part from the roles that the internet and social media have played in spreading misinformation, sowing distrust of experts and elites and fostering a sense that everyone's opinion is equally valid, however misinformed.

This graph illustrates how people's confidence levels can be driven by their level of skill and knowledge — or lack thereof. (David Dunning and Justin Kruger)

But Dunning thinks the interest has been amplified by the current political climate.

"I think it became bigger in politics because partisanship has become bigger, at least in the U.S. There's much more divisiveness in terms of the beliefs people have in the political sphere and what they're willing to say about the other side. And what they're willing to believe to support their own side."

Click 'listen' above to hear the interview.


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