Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
How students’ non-school inputs respond to ability grouping may explain the currently mixed findings in the literature about the impacts of tracking. Using data from South Korea, where students are randomized into middle schools under the country's equalization policy, but sorted into different high schools on the basis of achievement in some non-equalization policy areas, I find that under ability sorting, students’ demand for private tutoring, self-study time, and grade anxiety levels are lower, and their hours of sleep and leisure are higher. The effects on private tutoring are particularly significant for high achievers, while the effects on self-study and leisure hours are strong for low achievers. The results potentially help reconcile the mixed findings in the ability grouping and tracking literature.