Social Interactions in High School : Lessons from an Earthquake

We provide new evidence on the impact of peer effects on the schooling decisions of teenagers. In November 1980 a major earthquake hit Southern Italy. In the aftermath, young men from certain towns were exempted from compulsory military service. We show that the exemption raised high school graduation rates of boys by more than 2 percentage points by comparing high school graduation rates of young exempt men and older not exempt men from the least damaged areas and men of the same age groups from nearby towns that were not hit by the quake. Similar comparisons show that graduation rates of young women in the affected areas rose by about 2 percentage points. Since in Italy women are not subject to drafting, we interpret these findings as evidence of social effects of the decision of teenage boys of staying longer in school on that of teenage girls. Our estimates suggest that an increase of 1 percentage point of male graduation rates raises female probability of completing high school by about 0.7-0.8 percentage points. A series of robustness checks, including comparisons across different age groups and with different definitions of the comparison areas, suggest that the rise was due to the earthquake-related exemption, rather than other factors