Source: University of Utah, 2005
Ashkenazi Jews have the highest average IQ of any ethnic group for which there are reliable data. They score 0·75 to 1·0 standard deviations above the general European average, corresponding to an IQ of 112–115. This has been seen in many studies (Levinson, 1959; Backman, 1972; Romanoff, 1976), although a recent review concludes that the advantage is slightly less – only half a standard deviation (Lynn, 2004). This fact has social significance because IQ (as measured by IQ tests) is the best predictor we have of success in academic subjects and most jobs. Ashkenazi Jews are just as successful as their tested IQ would predict, and they are hugely overrepresented in occupations and fields with the highest cognitive demands.
During the 20th century, they made up about 3% of the US population but won 27% of the US Nobel science prizes and 25% of the ACM Turing awards. They account for more than half of world chess champions.