What's Math Got to Do With It? Multidimensional Ability and the Gender Gap in STEM

This paper studies the relationship between pre-college skills and the gender gap in STEM majors. Using longitudinal data for the United States, I estimate a discrete choice model of initial and final major choices in which college students sort into majors based on observed characteristics and unobserved ability. More specifically, I distinguish observed test scores from latent ability. I find that math test scores significantly overstate gender gaps in math problem solving ability. Math problem solving ability strongly predicts STEM enrollment and completion for men and women. I further explore the importance of math self-efficacy, which captures students’ beliefs about their ability to perform math-related tasks. Math self-efficacy raises both men’s and women’s probability of enrolling in a STEM major. Math self-efficacy also plays a critical role in explaining decisions to drop out of STEM majors for women, but not for men. The correlation between the two math ability components is higher for men than for women, indicating a relative shortfall of high-achieving women who are confident in their math ability. Lastly, I estimate the returns to STEM enrollment and completion and find large returns for high math ability women. These findings suggest that well-focused math self-efficacy interventions could boost women’s STEM participation and graduation rates. Further, given the high returns to a STEM major for high math ability women, such interventions also could improve women’s labor market outcomes.