[HelloMcFly]

Do you have evidence for that? I've worked on cognitive ability testing as it related to workplace performance, and have never seen anything that deviated dramatically from a normal distribution, especially at the high end.

[nostrademons]

Google [iq fat tails] and there're a bunch of articles on it (and one comment I wrote here about 4 years ago). The original data source for most of the articles is Terman's 1921 study of high-IQ people; they've plotted out the observed frequency of Terman's data against a normal distribution and found that it deviated markedly after about 3-4 SD.

Some additional Googling seems to have found some other independent studies:

http://hiqnews.megafoundation.org/John_Scoville_Paper.htm

http://www.abelard.org/burt/burt-ie.asp

I'm curious what sort of population your work draws from. The results above showed that IQ follows a normal distribution until about 140; other papers I've read indicate that IQ correlates with life outcomes until an IQ of about 140, and then appears completely uncorrelated. If you're studying workplace performance, I wouldn't be surprised if a good fraction of high-IQ people simply aren't in the workplace. (See eg. Christopher Langan.)

[gwern]

> other papers I've read indicate that IQ correlates with life outcomes until an IQ of about 140, and then appears completely uncorrelated.

Cites? The papers I've read, from the Terman study and the SMPY kids, don't show that.

[nostrademons]

The citation I was thinking of was from Daniel Goleman's Working with Emotional Intelligence, where one of the findings presented was that a moderately high IQ (usually in the 120-130 range) is often a prerequisite for entering a demanding profession like doctor, lawyer, or computer programmer, but continued success in the field depends more upon emotional skills like confidence, perseverance, resilience, social skills, and leadership.

With a bit of Googling, I've found some other support for this, including the Terman study:

http://www.eskimo.com/~miyaguch/grady/emptypromise.html

"Our conclusion is that for subjects brought up under present-day educational regimes, excess in IQ above 140 or 150 adds little to one's achievement in the early adult years." - Louis Terman, 39th Yearbook of the National Society for the Study of Education Part I, pp. 83-84

[gwern]

> ut continued success in the field depends more upon emotional skills like confidence, perseverance, resilience, social skills, and leadership.

Eh. That simply sounds like the correlation weakens a bit, but is far from the claims people make like 'IQ is irrelevant'.

> "Our conclusion is that for subjects brought up under present-day educational regimes, excess in IQ above 140 or 150 adds little to one's achievement in the early adult years." - Louis Terman, 39th Yearbook of the National Society for the Study of Education Part I, pp. 83-84

Terman may have thought so, but with the full dataset this is clearly not so. Check out http://www.iza.org/conference_files/CoNoCoSk2011/gensowski_m... 'The Effects of Education, Personality, and IQ on Earnings of High-Ability Men', Gensowski et al 2011; IQ never stops mattering, even if personality factors start to matter more.

(Always funny how people can look at a study which goes something like 'X correlates .4 and Y correlates .3, but in the top 1% by X, the correlations are .3 and .4 respectively' and go 'X doesn't matter!' Says something about what they want to believe about X, I think.)