Psychology and Relationships

This is the personality test you should take, says psychologist—it's a 'better predictor of behavior'

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Personality tests are often treated as objective assessments of one's innermost intentions. People relish using their results as justification for their less understandable impulses. 

There is something that personality tests such as the Enneagram and Myers-Brigg aren't telling you, though: It is possible to have a bad personality. 

"They don't get into the dirty underbelly of personality," said David Watson, a professor of personality psychology at the University of Notre Dame.

There is one test that might be better at reflecting what personality traits you have and how that could affect your behavior, he said: the International Personality Item Pool Test, or IPIP.

'Academic personality research tends to be trait-based'

Like other tests, the IPIP presents a series of sentences, and respondents denote how much they agree or disagree with them. 

"Have a vivid imagination" and "Get angry easily" are among the dozens of statements you can mark as "very inaccurate," "moderately inaccurate," "neither accurate or inaccurate," "moderately accurate" or "very accurate." 

The test will then tell you how much of the following five personality traits you seem to have: 

  • Extraversion
  • Agreeableness
  • Conscientiousness
  • Neuroticism
  • Openness to experience 

"Academic personality research tends to be trait-based," Watson said. This is often a "better predictor of behavior," he said, than the more popular personality tests. 

[Personality tests] don't get into the dirty underbelly of personality.
David Watson
University of Notre Dame professor of personality psychology

'If you study society, is everybody nice?'

The IPIP test doesn't provide what is probably the most satisfying part of the personality test experience: a type.

Like astrology, many of these personality tests combine characteristics into one neat little box.

"One thing people seem to like are typologies," Watson said. 

It doesn't hurt that the box tends to be very forgiving.  

"The types themselves are all couched in positive terms," Watson said. "The thinker. The creator. They come up with these positive ways of describing people, which are nice for people to hear. But if you study society, is everybody nice?" 

This is especially problematic when people use personality tests to date or hire, both of which happen frequently. 

Some companies hire Enneagram coaches for corporate retreats, believing the results will help workers understand each other's strengths, weaknesses and tendencies better. In South Korea, online daters use Myers-Brigg results to weed out potential duds. 

"The problem with compatibility is that there are a lot of people who don't have an attractive set of traits, and who are they compatible with?" Watson said. "There are people who have more toxic traits." 

If you want to learn more about yourself, the IPIP test is a much better gauge than other personality tests, Watson said.

But as with everything in life, take it with a grain of salt. 

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