People who are quick to lose their temper are also more likely to overestimate their intelligence, a new study reports.

Anger and optimism

Not all negative emotions are created equally. Feelings of anxiety and depression are typically associated with a more negative outlook on life — but anger, one of the study authors explains, is more closely linked to optimism. People who are angrier are just as optimistic as people who are generally happy.

“In a recent project, I examined the relationship between anger and various cognitive functions. I noticed from the literature review that anger differs significantly from other negative emotions, such as sadness, anxiety or depression. Anger is more approach-oriented and associated with optimistic risk perception and generally optimistic bias,” said study author Marcin Zajenkowski of the University of Warsaw.

Zajenkowski was wondering whether anger could influence other characteristics of people, namely how they perceive their own intelligence. So he carried out two studies with a sample size of 528 undergraduate students, assessing their anger, their intelligence, and their self-perceived intelligence. Participants undertook an array of 2-4 fluid intelligence tests (focusing on the ability to solve new problems, use logic in new situations, and identify patterns instead of relying on previously learned knowledge).

Researchers also evaluated the neuroticism and narcissism of the participants, looking for any associations and patterns.

The research revealed that anger was associated with an overestimation of one’s intelligence, though it was unrelated to one’s actual level of intelligence. In other words, if you lose your temper quickly, that doesn’t say anything about your intelligence — but it might say something about your self-perceived intelligence.

Interestingly, neuroticism, which was positively correlated with anger, tends to negatively correlate with self-assessed intelligence — so neuroticism acts as a suppressor for overestimating one’s intelligence.

However, this doesn’t really tell the whole story, due to a familiar problem that’s all too familiar in psychology.

The WEIRD problem

WEIRD stands for Western, Educated, Industrialized, Rich, and Democratic (as in living in a democracy).

Psychology studies overwhelmingly rely on WEIRD participants, which are typically undergrads — 67% of American psychology studies use college students, for example — and this is a problem because undergrads aren’t really representative for the whole population.

It’s easy to understand why researchers do this: gathering a large enough sample is complicated, and studies don’t typically receive that much funding. Undergrads are on campus (so they’re easily available), they often enroll for little or no money, and they can be quite homogeneous as a group — which allows scientists to detect small differences.

So while the study has been peer-reviewed and highlights an intriguing association, it also comes with the significant caveat: it addresses a very particular subset of the population, which may not be representative of the broader situation.

Journal Reference: Marcin Zajenkowski and Gilles Gignac. “Why do angry people overestimate their intelligence? Neuroticism as a suppressor of the association between Trait-Anger and subjectively assessed intelligence.” https://doi.org/10.1016/j.intell.2018.07.003