870: Personality Tests | Skeptical Sunday

Validity Issues

The Myers-Briggs Type Indicator (MBTI) faces significant criticism for its lack of scientific validity. Michael Regilio points out that 50% of people receive different results upon retaking the test, undermining its reliability 1. Jordan Harbinger highlights that the MBTI was developed by Katharine Cook Briggs and Isabel Briggs Myers, neither of whom were scientists, leading to its classification as pseudoscientific 2. Regilio notes that even Carl Jung, whose theories inspired the MBTI, dismissed such classifications as "nothing but a childish parlor game."

The characteristics measured by the test have almost no predictive power on how happy you'll be in a situation, how you'll perform at your job, or how happy you'll be in your marriage.

--- Adam Grant

This lack of predictive power raises questions about the test's widespread use in professional settings.

   

Popularity Factors

Despite its scientific shortcomings, the MBTI remains popular due to its appealing simplicity and the Barnum effect. Jordan Harbinger explains that the test's flattering and vague descriptions allow individuals to see themselves positively, akin to horoscopes 1. This effect leads people to accept generalized statements as uniquely applicable to them, fostering a sense of personal insight 3. Michael Regilio adds that the test's popularity is bolstered by its use in social media and casual settings, where the stakes are low and self-reflection is encouraged.

The results of the test are flattering and vague, so anybody who gets the results, no matter what their personality is like, wow, you nailed it.

--- Michael Regilio

This widespread adoption underscores the human tendency to seek simple explanations for complex personalities.

   

Corporate Use

Corporations and federal agencies extensively use personality tests like the MBTI, despite their questionable validity. Michael Regilio reveals that 89% of Fortune 100 companies and 200 federal agencies, including the CIA, employ these tests in hiring processes 4. This widespread usage persists even though leading psychologists on the board of CPP, the company behind the MBTI, do not use it professionally due to its lack of scientific credibility 5. Jordan Harbinger questions why such an unscientific tool is so prevalent in critical decision-making processes.

Personality testing is roughly a $2 billion industry. Obviously, not all personality tests are the Myers Briggs. Some of them are newer, better research tests, but they are not without problems.

--- Michael Regilio

This reliance on flawed assessments highlights the need for more accurate and unbiased tools in professional environments.