The people who take the survey know that their IQ contribution is going to be watered down by the 1000 other people taking the survey.
I have thought of that. But a person who wants to lie about his IQ would think this way: If I lie and other LWers do not, it is true that my impact on the average calculated IQ will be negligible, but at least it will not be negative; but if I lie and most other LWers also lie, then the collective upward bias will lead to a very positive result which would portray me in a good light when I associate myself with other LWer...
That most people lied about their IQ, and fudged their SAT, ACT and personality type data to match, or that they're telling the truth?
Scores on standardized tests like SAT and ACT can be improved via hard work and lots of practice -- there are abundant practice books out there for such tests. It is entirely conceivable that those self-reported IQs were generated via comparing scores on these standardized tests against IQ-conversion charts. I.e., with very hard work, the apparent IQs are in the 130+ range according to these standardised tests; but when i...
Clarity cannot be over-valued; plausibility, however, can be under-valued.