Wednesday, March 29, 2006

European IQs

From The Times of London, March 29, an article about the average IQs in various European nations, according to data from Richard Lynn, University of Ulster.

I'm reproducing the table from the article here, plus adding a column for population, using the World Factbook from cia.gov.


The IQ League

107 Germany 82.4 million
107 Netherlands 16.4 million
106 Poland 38.6 million
104 Sweden 9.0 million
102 Italy 58.1 million
101 Austria 8.2 million
101 Switzerland 7.5 million
100 British Isles 60.4 million
100 Norway 4.6 million
99 Belgium 10.4 million
99 Denmark 5.4 million
99 Finland 5.2 million
98 Czech Republic 10.2 million
98 Hungary 10.0 million
98 Spain 40.3 million
97 Ireland 4.0 million
96 Russia 143.4 million
95 Greece 10.7 million
94 France 60.7 million
94 Bulgaria 7.5 million
94 Romania 22.3 million
90 Turkey 69.7 million
89 Serbia 10.8 million


Of what use is this data? Anyone who has followed discussions on cosmicvariance.com and motls.blogspot.com about ex-Harvard President Lawrence Summers' remarks on why there are so few women physicists, knows that one side believes that it is all explained by IQ distributions. IQs are distributed in a bell curve; the average IQ (or math ability) of men is slightly higher then the average for women (the difference is five points or less) and men's IQ distribution has a larger variance than women. The result is that at the extremes (very high or very low IQ, 3 or more standard deviations from the mean) there are many more men than women.

Well, the standard deviation is typically 12-15 points, and so we see, e.g., that the German mean IQ is a half standard deviation greater than the British mean IQ. We could estimate the number of people of the various nationalities with IQs above, say, 150, and Germany, with its large population and its 107 mean IQ would dominate.

So, here is a testbed to check whether the idea supposed to explain difference in outcome between men and women in physics faculty jobs, applies elsewhere. E.g., Germany should probably easily dominate the Math Olympiad among the European nations.

The other amusing thought is that Professor Lubos Motl, who has a rather high measured IQ (158 or 165 or something, I don't remember, you can search his blog) and who is from the Czech Republic is probably unique there, but Motls are a dime a dozen in Germany.

PS: for instance, go to a normal distribution calculator like this one. For a mean (for Czechs) of 98, and standard deviation of 12, the fraction above 160 is 0.00000012 and the Czech Republic with 10.2 million people will have approximately one such person (more precisely, 1.224). In this example, 160 is 5.167 standard deviations above the Czech mean, but only 4.417 standard deviations above the German mean; Germany will have approx. 0.000005 * 82.4 million = 412 such people; on a per capita basis people with such IQs are 42 times more common in Germany than in the Czech Republic.

PPS: I should make it clear that I think IQ is mostly humbug.

4 comments:

Human said...

What does IQ stand for?

Arun said...

"IQ" stands for "Intelligence Quotient". It is a quantity deduced from various kinds of standardized tests. Its proponents believe that it measures something intrinsic about human intelligence. Its detractors (including myself) note that at best, it is a ranking in a specific age group of a specific population of at best merely one dimension of human intelligence. A model like Howard Gardener's is more likely to correspond to reality.

CapitalistImperialistPig said...

I would prefer to think IQ was humbug, but there is a lot of evidence to the contrary. One assumption I have never seen demonstrated is the notion that IQ is normally distributed in each subpopulation. I personally find it highly suspect. The whole fat-tail business depends upon that assumption, but it seems highly suspect to me.

mannfred said...

Some information about IQ and ethnic groups are to find at http://statisticsoftheworld.page.tl