> There was once a poll of engineers at the tech company I work at, and I think the results were like 70% INTJ, 25% INTP, and 5% other. If MBTI lacked all predictive power, you would expect a distribution roughly equivalent to that of the general population.
You're assuming the types are proportionally represented in the general population, which we have no reason the believe even if the test works as advertised. For all we know urban environments are 70% INTJ.
> For all we know urban environments are 70% INTJ.
There are 16 categories, which means you'd expect about 6% in each if the test sorts evenly. It doesn't; in fact only between 2% and 3% of the population is INTJ. Unless one of the questions is literally "are you a tech worker", that's very conspicuous selectivity.
The test doesn't sort evenly. One of the most popular online test sites says in one of their descriptions - I forget which one - that "this is the rarest type with only x% of the population."
I had a female friend who was an INTJ, and told me that it was very rare among women. Being very, INTJ, she was referencing some rigorous statistics.
You're assuming the types are proportionally represented in the general population, which we have no reason the believe even if the test works as advertised. For all we know urban environments are 70% INTJ.