[Part 1 of a topic suggested by @mmace134]
The Myers-Briggs Personality Test is very, very popular. It’s used as a predictor of career paths, of relationship styles, of leadership ability. Basically, you take the test and answer a bunch of questions like “Do you enjoy having a wide circle of acquaintances?” (To which you can only respond “Yes” or “No”. Based upon tens of answers, you’re given a four letter code, like INTJ or ENFP. Each letter codes for a specific trait, with two possibilities for each.
This all seems fairly reasonable–we can all agree that some people are more extraverted and some are more introverted. Some people make decisions based on feelings and some people don’t. The problem is, the test is based on the idea that people are one or the other–that is, that most people are overwhelmingly extraverted or overwhelmingly introverted. If that was the case, we would expect a graph of scores of introversion and introversion to look like this:
That’s a bimodal graph–one with two peaks. Those should represent the extraverts and the introverts (or the Thinking people and the Feeling people, or the Sensing and the Intuitive people).
The problem is, what we actually get is this:
…a unimodal graph. A bell curve. A normal distribution.
Most people fall near the center of the Introversion/Extraversion, Thinking/Feeling, Sensing/Intuitive, and Judging/Perceiving spectrums. Of course, there are people scoring very highly for one or the other–but they’re not the norm. This wouldn’t be terribly problematic if the Myers-Briggs didn’t insist on divvying people up into one or the other, which they do by splitting the responses down the middle.
That means if I’m just slightly to the left of center, because I’m pretty extraverted, but I don’t enjoy having a huge group of friends, I’m in the Introverted category, along with everyone who thinks gatherings of more than three people are hell. But aren’t I closer in type to people who are just to the left of center? Yep.
And nearly half of the research on the Myers-Briggs is done by institutions that benefit or publish the test in the first place. [*makes skeptical face*]
Want a validated personality test? Try the Big Five Personality Inventory