Slate has been having a debate on sex differences. Along the way, they hit on a key Summers issue: The apparent higher male variability of math scores. Shaffer, the author, refers to the classic Feingold piece, a cross-cultural meta-study of the variability of mental abilities across genders. Shaffer makes the common claim that there are data on both sides–sometimes women have a higher variance, and sometimes the men do. But is the difference statistically significant?
I did a simple analysis of Feingold’s data from 54 math tests from 20 countries, and 19 tests of spatial ability from 9 countries. I ran least squares and least absolute deviation tests.
Here are the p-values for the restriction that men and women have equal variability:
Math, least squares: p