Unlike the official MBTI test, most of the online tests haven't undergone rigorous statistical analysis. Yet people discuss various online tests, saying things like, "that's a good test", "that test is crap", etc.
What I want to know is if there isn't much in the way of statistical analysis measuring a tests validity and reliability, on what basis are people judging which tests are the better ones?
Here are some factors that I think may play a role:
Length. Not too long or too short.
I think people tend to prefer tests where the results describe them well.
Tests that don't create false dichotomies.
Interesting or thought provoking questions.
Adequate answer choices. By this I mean, people might get frustrated if there are too many questions where none of the choices apply or they can never narrow it down to just one.
Not too predictable. Some test questions are overly transparent. You know exactly what each question is testing for. I prefer it when the questions ask more indirectly.