Girls, Mathematics, and Sexual Equality

The Economist reports on a study published in Science this week* that compared mathematics and reading scores of 15-year olds from 40 different countries. The twist: they also compared the test results to measures of "social sexual equality", including economic and political opportunities, education and well-being for women, cultural attitudes towards women, female economic activity in a country, and women's political participation. Their result (see chart):

On average, girls' maths scores were, as expected, lower than those of boys. However, the gap was largest in countries with the least equality between the sexes (by any score), such as Turkey. It vanished in countries such as Norway and Sweden, where the sexes are more or less on a par with one another. The researchers also did some additional statistical checks to ensure the correlation was material, and not generated by another, third variable that is correlated with sexual equality, such as GDP per person. They say their data therefore show that improvements in maths scores are related not to economic development, but directly to improvements in the social position of women.

There were still some gender differences that did not appear to be little affected by culture: boys were better at geometry and girls were better at reading - although their reading scores relative to boys also improved as their social position did.

The article suggests that the fact that girls do so well in reading might be part of the reason why women aren't better represented in "maths-heavy" professions such as engineering in societies where they do as well as boys in mathematics.

However, as David Ricardo observed almost 200 years ago, economic optimisation is about comparative advantage. The rise in female reading scores alongside their maths scores suggests that female comparative advantage in this area has not changed. According to Paola Sapienza, a professor of finance at Northwestern University in Illinois who is one of the paper's authors, that is just what has happened. Other studies of gifted girls, she says, show that even though the girls had the ability, fewer than expected ended up reading maths and sciences at university. Instead, they went on to be become successful in areas such as law. In other words, girls may acquire an absolute advantage over boys as a result of equal treatment.

I don't agree that career choice is necessarily only about economics, since we aren't exposed to and encouraged to pursue all fields equally. A boy who builds soap box cars with his dad and who is praised for his math skills may be more likely to find himself interested in engineering than a girl who is encouraged to bake cookies with her mom and is praised for her writing ability, even if that girl and boy actually turn out to have similar mathematical ability.

For more discussion about career "choice" in science and engineering see the posts at echidne of the snakes, The World's Fair, and Pure Pedantry on the recent Boston Globe article that claims "When it comes to certain math- and science-related jobs, substantial numbers of women - highly qualified for the work - stay out of those careers because they would simply rather do something else."

* Guiso L et al. "Culture, Gender and Math" Science 320(5880):1164-1165 (2008). DOI: 10.1126/science.1154094

Tags: education, gender gap, mathematics