Girls’ comparative advantage in reading can largely explain the gender gap in math-related fields

Researchers Thomas Breda and Clotilde Napp lay out the comparative advantages that explain the underrepresentation of girls in scientific fields.

While girls have more successful academic trajectories than boys, obtaining better results in their SATS and pursuing higher education more often, they are still noticeably underrepresented in math-related fields. In fact, only one third of enrolled students in engineering schools is female. Jobs in these fields are often the best compensated, in growth industries, and have the lowest rates of gender wage inequality. However, gender differences in math performance are now minor in most countries and cannot explain gender discrepancies in terms of choice of field of study or career. Social scientists have therefore turned to other potential factors, including gender differences in self confidence, individual preference, and discrimination.

In an article published in PNAS, Thomas Breda and Clotilde Napp look at gender differences in a new light. They consider the role played by academic performance, showing that taking literature (or reading) scores into account alongside scores in math can go a long way towards explaining gender discrepancies in educational trajectories.

Slight Differences in Performance

They use individual-level data from the 2012 Program for International Student Assessment (PISA) study . Studying student performance in reading and math from a sample of 300,000 15-y-old students in 64 countries (the 35 OCDE countries and 29 partner countries), they show that boys are slightly stronger in math and girls are a lot strong in reading. The gender performance gap in reading is three times as large as the difference in math. This difference gives girls a comparative advantage in disciplines related to reading/literature: two thirds of them are stronger in these subjects than in math (which is only true for one third of boys).

The PISA data also shows that more boys than girls intend to pursue math-intensive studies and careers, and that this difference is very noticeable in certain countries. They suggest that (the relatively minor) degree to which boys outperform girls in math can only account for about 10% of the gender gap in intent to pursue math-intensive studies and careers.

Very Different Intentions to Pursue Math-Related Studies

In contrast, the results are very different if we explain the intention to pursue studies or careers in a given discipline by comparative advantage in math rather by academic performance in math. When we control for comparative advantage, it explains 75% of the gender gap in students’ intentions to pursue math-intensive studies in all 64 countries in the study. This means that if we focus our analysis on students of both genders whose scores differ to the same extent in math and in French language, the gender gap in students’ intentions to pursue math-intensive studies is reduced by around 75%. Girls generally perform better in reading/literature than in math; this comparative advantage in the humanities means that they identify as humanities people rather than science people, and that when it comes time to make decisions about their future fields of study, they abandon the mathematically-intensive options.

The 2012 PISA study also includes information about students’ declared intention to study math and their confidence in their performance in the subject. Comparative advantage goes much further to explain gender differences in academic trajectories than these other variables.

Improving Access to Information at Decision-Making Time

We can observe the same phenomenon when we try to explain gender differences in professional trajectory: performance in math cannot adequately explain the difference between boys and girls when it comes to declared interest in math or self confidence about math whereas comparative advantage almost always can. This shows that self confidence or interest in a given subject is established by comparing one’s performance in that subject vis à vis one’s performance in others: even if girls perform as well as boys in math, the fact that they perform so much better in reading/literature changes how they perceive their mathematical ability and their self-confidence in math.

The researchers wanted to find out more about the origins of the gender differences in academic performance and comparative advantage at the age of 15, given the pivotal role they play. In an earlier article published in Science, the researchers suggest these are probably largely cultural, determined by socialization processes at home and at school. For example, they note that gender differences in academic performance are greater in countries where stereotypes associating boys with mathematics are more ingrained, and suggest that the general organization of a country’s educational system could limit these differences.

To ensure a more even gender distribution in math-intensive fields, one potentially effective approach could be to limit comparative advantage by focusing, for example, on improving the literacy skills of boys. Another option could be to better inform students about the potential repercussions of their academic choices to encourage them to think less about comparative advantage and more career prospects. Of course, these options should complement rather than replace interventions directly aimed at limiting the negative effects of gender stereotypes on the academic trajectories of both girls and boys from an early age.