Good Schools or Good Students? Evidence on School Effects From Universal Random Assignment of Students to High Schools (WP-23-45)
Paulo Bastos, Julian Cristia, Beomsoo Kim, and Ofer Malamud
How much do schools differ in their effectiveness? Recent studies that seek to answer this question exploit random assignment generated by central allocation mechanisms or oversubscribed schools. However, the resulting estimates, while causal, may also reflect peer effects due to differences in student composition across schools. The researchers exploit universal random assignment of students to high schools in certain regions of South Korea to provide estimates of school effects that better reflect the effects of school practices and policies. They find significant effects of schools on scores in high stakes college entrance exams: a 1 standard deviation increase in school quality leads to 0.05–0.08 standard deviations higher average academic achievement in Korean and English. Analogous estimates from areas of South Korea that do not use random assignment, and therefore include the effects of student selection and peer effects, are substantially higher.