Two Out of Three people Are Ambiverts

I learnt a new word last week: Ambivert. It was first coined Kimball Young in 1927 and is defined as a person exhibiting features of an extrovert and an introvert. Finally I had the solution to one of the nagging problems in my life: the forced division of people by Myers-Briggs into either Extroverts or Introverts.

Most of us have suffered from one of the more common cognitive biases: the Illusion of Superiority. We all tend to overestimate our positive qualities and abilities and to underestimate our negative qualities. Parents in particular do this with their young children. However once you have studied statistics and learned about the Normal Distribution you realise that half of us are below average and half above. Even more significant is that 2/3rds of any population cluster within plus or minus one standard deviation. It is not called the Bell Curve for nothing.

Despite the popularity of Myers-Briggs I was never comfortable with its forced divisions I or E, S or N, F or T, P or J. Yes, there is a division between male and female but for most biological characteristics the Normal Distribution rules and this would include a personality factor such as extraversion.
Why is this distinction important? There is a widely accepted assumption that the best salespeople are extraverts. A recent study was carried out by Adam Grant, the youngest tenured professor at the Wharton Business School. He examined a software company with a large sales staff, assessed where each salesperson stood on a 1 to 7 introversion/extraversion scale, and then charted how much they sold over the next three months.

There would be no surprise that strong introverts (the people represented on the left of the chart’s horizontal axis, around 1 and 2) were not very effective salespeople. But the strong extraverts (those over to the right, around 6 and 7) weren’t much better. The best were those in the middle known as ambiverts.
More than 10,000 companies, 2,500 colleges and universities and 200 government agencies in the United States use the Myers-Briggs. Over 2 million people take the test annually and are accepted or rejected accordingly either into employment or for promotion. Yet despite its widespread the test is highly questioned by the scientific community. No major journal has published research on the MBTI, which academics consider a strong repudiation of the test’s authority. Carl Thoresen, a long-time and highly regarded professor of psychology at Stanford, is the Chairman of company that markets Myers-Briggs, CPP. Yet of the roughly 150 papers he has published in his career, there isn’t one mention of Myers-Briggs.

Please note that I am not arguing against personality tests. There has been considerable progress in personality testing since the Myer-Briggs test was first published 50 years ago. Tests such as the Five Factor pass reliability and validity tests, unlike the Myers-Briggs, and are based on legitimate scientific models such as the Normal Distribution. A scientifically based personality test can reduce the people risk when hiring or promoting someone by around half. Yet many organisations continue to use Myers-Briggs despite it being an instrument rejected by the scientific community and probably causing more harm than good.

I am reminded of the words of Tim Michen:
Science adjusts its views based on what’s observed,
Faith is the denial of observation, so belief can be preserved.