[ben_w]

Owing to the way IQ is defined, nobody has an IQ over 200.

IQ doesn’t measure absolute intelligence, but rather assumes it is a normal curve and maps that to human friendly numbers: mean 100, standard deviation 15 or 16 depending who you ask.

The same thing has the curious side effect that if the number of people in comas at any given time is greater than 1, then coma patients must have an IQ > 0.

[tempestn]

OK, so if all IQs could be mapped accurately onto a normal curve with a SD of 15-16 you wouldn't expect anyone over 200. But standardized IQ tests can most definitely give results over 200, and do. And presumably someone who scores 250 on an IQ test is likely to be more intelligent^ than someone who scores 200 on the same test.

^in the sense that it measured by IQ tests, anyway. Point being it shows a real difference; deltas over 200 aren't meaningless.

[lazyjones]

> And presumably someone who scores 250 on an IQ test is likely to be more intelligent^ than someone who scores 200 on the same test.

Unless the former has taken the same test or some subset of the questions before. Which isn't unusual...

[harry8]

Terence Tao's intelligence is not predicted by IQ. Plenty have higher IQ and achieve less. Some lower and achieve more.

IQ is total pseudoscience nonsense of zero value to anyone or anything.

It's one genuine use is as a fig leaf for the very worst kind of racism. Treat it and anyone touting IQ an indicator of anything with extreme suspicion. Nazis love IQ. Goodwin's. /Thread

[tyho]

Why do you consider IQ to be pseudoscience? It's the bedrock of psychometrics. Just because some people use some IQ data to justify racism doesn't mean the measure is unscientific. Nazis loved nuclear physics too, it doesn't mean the field is pseudoscience.

[brennanpeterson]

Take any large multivariate problem and look for a regressor against some dimension. Say, car speed. You will find that there is a good variable that links that. But that variable won't be explanatory or even correct.

A much better explanation here, from the fairly wonderful blog of cosma shalizi http://bactra.org/weblog/523.html

And most importantly, it won't be predictive.

[ben_w]

I know this isn’t your main point, and I might just be remembering British wartime propaganda (my parents told me several things that later turned out to have been that), but…

Wasn’t the Nazi nuclear program severely delayed by their race-based hatred of Einstein for being Jewish?

[wutbrodo]

This is an argument against doing physics the way the Nazis did (ie deriding certain theoretical paths as "Jewish physics"), not an argument against doing nuclear physics at all because the Nazis did.

The latter is what this thread is talking about: it's obvious that we shouldn't be studying psychometrics the way the Nazis did, but it's not obvious that we shouldn't be doing it at all because they did (as with nuclear physics).

Hilariously, even harry8's complaint that the Nazis loved IQ is precisely backwards: Hitler banned IQ testing for being "Jewish" too.

EDIT: I actually was curious about this last claim, so I checked the source that the Wikipedia article points to. While this text was written by one of the most-cited psychologists in history, there's little else out there to concretely corroborate or refute that IQ testing was _banned_ by the Nazis. The evidence indicates that their attitude was somewhere between apathy and hostility towards the tests.

[harry8]

No you're a bit too literal. Nazis sadly are not dead and gone, not limited to 1930-45 Germany.

IQ is loved by Nazis as proof of master race bullshit. Really.

Treat IQ with contempt. It's an indicator of idiocy in a discussion. (All of us are capable of idiocy in discussions, including me, don't fall for the IQ trap. You're above it. We all are).