Guys both those 15% and 50% reliability figures for MBTI come from their own data:


Only half the people re-taking the test end up with the same of the 16 types (Table 12, p. 7). Absurdly, the claim that only 15% of the test-takers get different results seems based on test-reliability if you treat each of the sub-scales as continuous measures (p. 7).

When it's a coin toss whether you'll end up with the same type, it's not surprising that personality-career match isn't linked to greater success or satisfaction. This has been studied to death for decades. There's so much $ spent on MBTI subscriptions that it's implausible to me the test predicts something but we've missed it. This test is a scam.

Tom described these sorts of theory-driven tests as "making stuff up," but that's not the problem. It's fine to create tests based on a theory and see if they predict what you'd expect from your theory. The problem with MBTI is that it's predictions are repeatedly disconfirmed. But MBTI is a huge industry. This is textbook over-hyped bad science with a massive conflict of interests. You went too easy on it.

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Good episode! Emotional intelligence up next.

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And I call hindsight bias on how you ended this episode. The factor analysis approaches did not yield obvious results, and there was no reason to think ahead of time that they’d predict our behavior as well as they do.

For one thing, the traits that go into the 5 or 6 factors aren’t intuitive. People don’t guess that they cluster together in advance. It’s just like the general factor of intelligence. People think it’s obvious now but there was no reason to expect different domains of cognitive performance would be correlated.

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I am skeptical about universal personality measures. I was always an “introvert” and thought that was my “natural personality” until I lost weight: then I found myself being more extroverted because suddenly everyone was acting nicely toward me! I discovered this is very common among people who have gotten cosmetic surgery or otherwise changed their outward appearance. Personality is to a certain extent learned behavior: if people have always treated you badly, then you probably don’t feel energized or motivated being around them.

I also wonder about the role of pain in “personality.” I’ve worked with animals who were described as having angry or reactive personalities when it turned out they were just injured in ways that were not immediately visible. Many “disagreeable” people I know also turned out to have underlying health conditions.

Also I can’t believe the field of personality studies relies on people to assess themselves. How would we know what we are really like, when we have never been anyone else? The most narcissistic and dysfunctional people I know would describe themselves as agreeable and conscientious—because everyone in their lives is too busy avoiding them to set the record straight.

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Fun episode! One quibble is that you sometimes slip on the distinction between factors and clusters; they are quite different and you can find different numbers of clusters within a 5-factor model... e.g. https://psycnet.apa.org/record/2011-23215-004 .

Factors are best thought of as independent dimensions -- so imagine some axes with Conscientiousness on the X axis, Agreeableness on the Y axis, Openness to experience on the Z axes, (and two more axes that are hard to visualise). The clusters are clusters of individuals with similar CANOE scores.

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Interesting episode. Was struck by the fact that personality does change over time, but still keeps within the overall traits of an individual person (hope I got that right!) It did leave me wondering how much of the ‘self improvement’ type of change you see on social media is real - how to become more calm, more assertive etc. You’re really fighting against a set of personality traits that aren’t going to budge however much mindfulness you practice....

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Great episode! Since you discussed problems with the Myers-Briggs, I recommend this really nice article summarizing issues with the test (It was written by my master's advisor, so I may be biased): https://areomagazine.com/2021/03/09/should-you-trust-the-myers-briggs-personality-test/

You also discussed a paper by Gurven et al. showing that the Big Five did not replicate in a small-scale society. He and his colleagues published a more recent paper advancing a theory for why that may happen: https://www.nature.com/articles/s41562-019-0730-3

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