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This claim was made popular by being said in the movie The Social Network. It exactly says:

Did you know there are more people with genius IQs living in China than there are people of any kind living in the United States?

Peter Mortensen
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isJustMe
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1 Answers1

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This claim can actually be tested very easily. Others have done it, e.g. Brian Dickerson: The perils of repeating political nonsense and came to the conclusion that the claim was wrong.

You just need the chance a random person from a large group has a genius level IQ, then multiply it with the number of people in China and compare the result with the number of people in the USA. The IQ follows a Gaussian distribution where 100 is the mean by definition and a standard deviation (SD) of 15 (after Wechsler) or 16 (after Stanford-Binet). (sources: [1], [2]). The rarity of a particular IQ can be calculated easily and are listed by [1]. This numbers give the percentage of people with an IQ equal or lower than the given IQ and the rarity of this occurring.

The main question actually is what an genius level IQ is. According to [3] it is 140 or higher ("Genius or near genius") while [4] states it as at least 160. The rarity of such an IQ is 1/261 (with a SD of 15) or 1/161 (SD=16) for an IQ of 140 and 1/31,560 (SD=15) or 1/11,307 (SD=16) for an IQ of 160 [2].

The population of USA for 2012 is about 313,221,000 according to the U.S. Census Bureau [5]. The population of China for 2011 is about 1,370,537,000 [6]. Taking the lowest rarity of 1/161 from above then there are about 1,370,537,000/161 = about 8,513,000 geniuses in China, which is significantly less then the 313,221,000 Americans. If you take the 15 SD value of 1/261 then you get only about 5,251,000 Chinese geniuses. With the 160 IQ points, which are more realistic [7] to indicate a real genius, the numbers are even smaller (about 43,400 or 12,100). Note that 1,370,537,000/313,221,000 = 4.375, so in order for this claim to be true actually one of every four (or say five) Chinese would need to be a Genius. Even without the numbers above, it can be easily understood that this is not the case.

Conclusion: This claim is wrong according to the definition and probabilities of the IQ.

Supplement:

It has been pointed out, that there are published research results [7] showing that China and other Asian countries have a higher average IQ of about 106 (or even as high as 115) as the normed average of 100. This would increase the number of geniuses in China: The above factor of 1/161 would drop to about 1/60 or, for a Chinese average of 115, even to about 1/17. These numbers can be easily calculated using the standard deviation, e.g. using MS Excel's function NORM.DIST(140, 106, 16, TRUE). However, both these factors are not in any way close to the US/Chinese population ratio of about 1/4.375, so the original conclusion still holds.

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Martin Scharrer
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    Doesn't this assume a proportional distribution of IQ between the 2 countries? I know it would take a lot to skew the numbers *that* much, but it does leave the numbers dubious? – Marc Gravell Mar 21 '12 at 19:01
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    @MarcGravell: Yes, it assumes that. Actual IQs might differ due to health, nutrition, education and other living conditions. Also you can assume that many of these are better on average in the USA than in China, so it counts against the claim. Your (now edited away) worldwide idea is good: 7,002,000,000 (World wide) / 313,221,000 (USA) = 22.35, so as long not every 22nd person in the world is a genius this claim can't be correct. While this is higher than the 4.375 before it is still out of the question that so many people on earth are geniuses. – Martin Scharrer Mar 21 '12 at 19:16
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    @MarcGravell: Even if the numbers are not very exact (especially given the missing exact definition of "genius") the last part says it all: Every forth Chinese would have to be a genius in order for this claim to be true. You don't need to do any actual math or research to understand that this can't be the case. – Martin Scharrer Mar 21 '12 at 19:20
  • Cool; tbaks for taking the time to edit – Marc Gravell Mar 21 '12 at 19:57
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    Not that this would invalidate your calculation, but the way it is written, it seems like you're saying that a genious IQ is 15 or 16 standard deviations above the mean, and not that the considered SD is of 15 or 16... – tpianca Jan 05 '14 at 01:19
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    @tpianca: Ok, I see what you mean. I rephrased it now. Thanks! – Martin Scharrer Jan 05 '14 at 09:50
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    I could believe, if told by someone more reliable than a movie, that *with suitable coaching and practice*, 1 in 4 of just about anybody could score 140+ on an IQ test. So I speculate that if this factoid isn't completely invented, it's the result of improper extrapolation and perhaps a mistaken belief that the coaching doesn't matter because the test is measuring something inherent. – Steve Jessop Jul 12 '14 at 17:52
  • @SteveJessop I think you can even break it down without any IQ-Tests at all. Imagine we would all be super-intelligent (like 140 IQ) would we all be geniuses? No - the Term genius usually refers to someone very exceptional. If every 4th chinese can do it, it is not very exceptional and would not meet the definition "genius" – Falco Feb 12 '15 at 15:05
  • @Falco: I don't see how that follows. If every 4th person in China was over 2m tall (or other boundary of your choice), we could still say firstly that there are more "very tall" people in China than people of any kind in the US, and secondly that the height of those people is, *from the perspective of the US*, exceptional. Naturally the Chinese would think nothing of being 2m tall, but an American would still think it worth mentioning. The question is whether it's *true*, not whether the Chinese would think "genius IQ" is anything special if it were true :-) – Steve Jessop Feb 12 '15 at 16:04
  • @SteveJessop maybe you are right. It is just that I see a different between "very tall" and "some of the exceptionally tallest people on earth" - and the term "genius" implies something like "extremely rare" for me which contradicts 25%. But maybe that is just subjective – Falco Feb 12 '15 at 16:06
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    @Falco: well, "people of any kind in the US" is something like 5% of world population, so granted it's questionable whether we *should* term the top 5% or more of IQ in the world "genius" even if that's what China had. But anyway the term "genius IQ" is rooted in historical interpretation of IQ tests and scores, and posting a genius IQ score doesn't really take a genius in the usual English sense! If China somehow did produce 350 million such IQ scores I think it would take a while to adjust the terminology. – Steve Jessop Feb 12 '15 at 16:09