Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We examine college students' interaction within classrooms and estimate peer effects on their academic performance. We exploit a unique seating rule at a university in South Korea, known as the fixed‐seat system. We propose a novel identification strategy based on students' repeated interaction. Our findings show that a student's performance in a class is significantly influenced by his or her next‐seat neighbor's ability. The effect is heterogeneous, varying by student and class characteristics. Also quantile regressions reveal that peer effects are significant among below‐average students and among those at the top end.