Closer Proximity to the Subway Network Implies Lower High School Test Scores: Evidence from a Subway Expansion

This paper identifies and quantifies the effects of better transport accessibility on student performance measured by mathematics test scores. A 24 km new subway line and the extension of an existing line in Santiago (Chile) in the mid-2000s reduced the distance between more than half of schools in the city and their nearest subway station. Estimates are derived using instrumental variables and fixed effects models that account for endogeneity in the relation between student performance and school-subway network distance. Substantial closer proximity to the subway network (5 km or more) is associated with lower test scores (11 percentage points of one standard deviation). I find evidence that some mechanisms could be an increase in the student/teacher ratio, an increase in parental hours of work and a worsening in the quality of peers of students in treated schools relative to students in control schools.