inFact with Brian Dunning inFact with Brian Dunning


Why the Myers-Briggs Test Is Hogwash

The Myers-Briggs personality test is used throughout society and many just assume it to be meaningful. The science shows otherwise.

Share Tweet

At some point in your life you've probably been given the Myers-Brigg Type Indicator test, and been assigned a 4-letter personality type. You were probably given the test by an employer, recruiter, or maybe a coach who hoped to help you find some life direction in which you would be the most successful. The promise is almost like having a crystal ball: will you be a better manager or a better employee? Should you work in this field or that field? In some cases, important life decisions are made for people based only on this test.

The test itself consists of about 100 simple questions, and the results are given as one of two letters in each of four dichotomies: Attitude, Perceiving, Judging, and Lifestyle. So every test taker ends up in one of 16 possible personality types: Executive, Caregiver, Scientist, Idealist, and so on. It seems like it's the miracle solution to making everyone happier and more productive, and every company more successful. Right?

Wrong. The first clue is that there is ONE industry that does not use the test: Psychology! Because they know that it's completely unscientific, and statistically, no better than a horoscope.

Myers and Briggs were not scientists or psychologists; they were a mother and daughter in the early 20th century. Although neither had any training or education in psychology, they were both fans of Carl Jung's writings on psychometry, and they thought they could do a better job. They first developed the test during World War 2 when there were a lot of women entering the workforce for the first time, and Myers and Briggs hoped their test would help them find jobs they would be most effective in. So, a good idea, and well intentioned.

But the test doesn't show your skills or aptitudes, it merely reflects your preferences, and those are two very different things. Half the people who take it again score differently, because our preferences change day-by-day, depending on our mood, our recent experiences, or other factors.

That's reflected in the data, which shows most people land somewhere in the middle of the bell curve for each of the four dichotomies. Take this one, the Introvert-Extravert dichotomy. Extreme introverts and extraverts make up the tails of the curve, but most people are somewhere in the middle. Myers-Briggs posits that this data describes two groups of people. It doesn't; two peaks would show two groups, one peak shows one group. Myers-Briggs cuts this bell curve straight down the middle — most people are near the line, which is why they score differently day to day — and this is a completely invalid statistical analysis of the data.

The result? Many scientific studies have found there's no correlation at all between people's aptitudes and career success and their Myers-Briggs score. That includes one of the early customers, the Army Research Institute, which concluded the science could not justify the use of the test in career counseling.

So, unfortunately, I do not have a magic crystal ball for you today that can make all of your hard decisions for you.

— Brian Dunning

Share Tweet


References & Further Reading

Dickson, D., Kelly, I. "'The Barnum Effect' in Personality Assessment: A Review of the Literature." Psychological Reports. 1 Feb. 1985, Volume 57, Number 2: 367-382.

Druckman, D., Bjork, R. In the Mind's Eye: Enhancing Human Performance. Washington, DC: National Academy Press, 1991.

Howes, R., Carskadon, T. "Test-Retest Reliabilities of the Myers-Briggs Type Indicator as a Function of Mood Changes." Research in Psychological Type. 1 Jan. 1979, Volume 2, Number 1: 67-72.

Jung, C. Psychological Types. New York: Harcourt, Brace & Company, Inc., 1923.

Long, T. "Myers-Briggs and Other Modern Astrologies." Theology Today. 1 Oct. 1992, Volume 49, Number 3: 291-295.

Myers, Isabel and Peter. Gifts Differing. Palo Alto: Consulting Psychologists Press, 1980.


Let us email you
about new and upcoming episodes: