The effect of siblings’ sex ratio on physical capital, human capital, and gendered time use among adolescents in Ethiopia
利用埃塞俄比亚青少年数据，研究发现兄弟姐妹中兄弟比例越高，青少年的身体和学业表现越好，尤其对男孩影响更大，但同时也增加了女孩做传统女性家务的时间，尤其在农村地区。
We examine the role of siblings' sex ratio on adolescents' physical and human capital development, as well as gendered time allocation using data from the Young Lives project in Ethiopia. We use BMI-for-age and Weight-for-age to measure physical capital and grade attainment and scores in Mathematics and English tests as human capital indicators. Gendered time use is proxied by the hours per day the adolescent spends doing traditionally female-specific chores. Our identification strategy relies on the absence of sex-selective reproduction in our study area which implies that for a given number of siblings, their sex ratio should be exogenous. Our results show that having relatively more brothers than sisters increases both physical and human capital for adolescents, typically with a stronger effect for boys. Yet it also increases girls' time spent on traditionally female-specific tasks, especially in the rural areas. This points to a complex relationship between siblings' sex composition and long-term life outcomes for women.