Does Helping John Help Sue? Evidence of Spillovers in Education
利用学生从多所小学升入同一所中学的自然过渡，本文提出新方法量化教师教学的同伴溢出效应，发现忽略这些溢出效应会使教师价值被低估至少30%，且溢出效应在同种族同性别学生群体中更显著。
Does the impact of teachers extend beyond the students in their classroom? Using the natural transitions of students from multiple elementary schools into a single middle school, this paper provides a new method for isolating and quantifying peer spillover effects of teaching and shows that ignoring these spillovers underestimates a teacher’s value by at least 30 percent. Because the spillovers also affect teacher value-added estimates, I develop a method of moments estimator of teacher value-added and show that accounting for the spillovers does not have a large impact on the ranking of teachers in New York City. I conclude by showing that the spillovers occur within groups of students who share the same race and gender, which suggests that social networks play a critical role in disseminating the effect.