Causal effects are usually estimated under the assumption of no interference between individuals. This assumption means that the potential outcomes for one individual are unaffected by the treatments received by other individuals. In many situations, this is not reasonable to assume. Moreover,...

We study within-family spillovers in college enrollment to show college-going behavior is transmissible between peers. Because siblings' test scores are weakly correlated, we exploit college-specific admissions thresholds that directly affect older but not younger siblings' college options....