Emil O W Kirkegaard

But it's also the case that the average IQ of this data set is well above national mean. Doesn't this seem... fishy? @pnin1957 or @KirkegaardEmil ?

Should be somewhat above the mean, SAT test takers are self selecting. Dunno how high but 110 (eyeball average) doesn't seem wildly implausible.

Yeah, mean IQ ~110 for people who take the SAT is reasonable (via selection bias). But with n ~= 200 (eyeballed) why is there no one above 130 IQ? I mean, if the sample mean is .6sigma above the population mean, shouldn't we expect more scores above 130?

The range restriction is bizarre, yes.

Presumably he used data based on a test with a low ceiling, e.g. WORDSUM.

Looking at this plot again, it looks like there is a 145 ceiling affect which is bending the top tail down. But also looks heteroskedastic (noisier at the top). Suppose it is; how should I roll that into my understanding? Should I do regressions on the logged variables instead?