Unveiling the effects of other-gender friendships: evidence from middle-school students in China

This paper investigates the effect of having other-gender friends on middle-school students' cognitive and noncognitive performance in the context of China. To address the endogeneity of the existence of other-gender friends, we rely on parents' strictness with friends-making and the share of other-gender schoolmates. We find that having at least one other-gender friend is estimated to have a significantly negative effect on students' Mathematics scores and a significantly effect on increasing students' negative mood states. Our estimates indicate that the negative effect of other-gender friends is more pronounced for girls, highlighting the importance of paying attention to girls who build the other-gender friendships during the transition from childhood to adolescence. By focusing on both cognitive and noncognitive performance, we are able to paint a more accurate picture of the impact of other-gender friends on the development of adolescents.