Does public school choice promote student diversity?" (joint with Danny Cohen-Zada and Itay Attar)

We estimate the causal effect of free school choice on student diversity as measured by the within school variation in student socio-economic status (SES) to test contradicting theoretical predictions. For this purpose, we exploit a large-scale policy program in Israel in which a rigid catchment-areas system (students being assigned to schools according to their home address) is gradually being replaced with free-choice among public schools within localities. The identification of causal effects is based on this staggered implementation across and within localities which generates variation in both timing and intensity of competition and facilitates a difference-in-differences design. Our results indicate a clear and robust increase in students' SES variation within schools following the introduction of free choice, which stems from schools that are initially more affluent and cities with higher initial inequality.