There's probably a bias towards sightly higher than average IQ, because extremely low IQ usually means intellectual disability, and because IQ correlates with t

There's probably a bias towards sightly higher than average IQ, because extremely low IQ usually means intellectual disability, and because IQ correlates with the ability to apply effort (at least at lower IQs). I also suspect but have no evidence that low IQ users tend to stay within walled gardens like Facebook more. I think a lot of HN would be surprised at what an IQ of 100 looks like.