The Economics Behind the Math Gender Gap: Colombian Evidence on the Role of Sample Selection

Literature has previously shown that boys outperform girls in math test scores. This so-called Math Gender Gap (MGG) varies across locations and increases with additional school grades. In this paper I suggest that the... [ view full abstract ]

Literature has previously shown that boys outperform girls in math test scores. This so-called Math Gender Gap (MGG) varies across locations and increases with additional school grades. In this paper I suggest that the observed patterns may be explained by sample selection caused by gender differences in the opportunity cost of schooling. I present and test a labor supply model that relates the opportunity cost of schooling to school attendance and thereby to the observed MGG. Using an exogenous policy change in Colombia, I estimate that sample selection may explain 42% to 67% of the MGG. Additionally, I find that the MGG is more strongly correlated with gender differences in employment than with traditional measures of gender inequality. Lastly, I estimate non-parametric bounds to evaluate if a positive MGG may be strictly attributed to male selection in the lower tail of the distribution.