Ruth Marcus: A group of researchers (all women, as it happened) looked at annual math assessments required by the No Child Left Behind law from 10 representative states that supplied details about gender and ethnicity, a total of 7 million students.
Their study, published in the July 25 issue of Science, found no differences between girls and boys in average performance -- not even, as earlier studies had found, once they entered high school. The gap between girls and boys on math SATs, they said, could be explained by the fact that more girls than boys go to college and therefore take these tests.
But, echoing Summers's point, there was small yet significant variance between the genders -- the degree to which the scores of girls or boys differed from the average. At the very highest level, the 99.9th percentile, the difference meant 2.15 males for every female. This difference was large enough that, in an occupation requiring math skills at that level, the job ranks could be expected to be filled 68 percent by men, 32 percent by women -- enough to explain, as Summers suggested, part of the gender gap.
Easy for HER to say!