Peer Effects in the Classroom: Evidence from New Peers

• Main Author: Pivovarova, Margarita
• Other Authors: Benjamin, Dwayne
• Language: en_ca
• Published: 2013
• Subjects: Education; Peer Effects; Standardized tests; Knowledge spillovers; Endogeneity; Instrumental Variables; 0501
• Online Access: http://hdl.handle.net/1807/43697

This thesis investigates the role of classmates in the academic achievement of an individual student. I propose a new strategy to identify ability spillovers and combine this strategy with a unique data set to estimate peer effects in education. Using this innovative approach, I quantify the average effect of peers on own academic achievement in middle school and analyze heterogeneity of own response to peers along ability and gender lines. In Chapter 1, I provide a comprehensive empirical analysis of linear-in-means model of peer interactions and estimate the effect of the average quality of peers on academic progress of six-graders in Ontario public schools. I provide convincing evidence of the validity of my identification strategy and show that the average quality of classmates measured by their lagged test scores matters for individual academic achievement. I find positive, large and significant ability spillovers from peers in the same classroom. To reconcile the broad spectrum of peer effect's estimates in the literature, I also investigate the impact of peers in the same school and grade. I show that once a peer group is aggregated to a grade or class level, the effect attenuates towards zero. In Chapter 2, I relax the main assumption of linear-in-means model and compare alternative models of peer interactions with the empirical results from the first chapter. My findings imply that all students unambiguously benefit from the presence of high achieving peers. At the same time, academic progress of high-achievers does not suffer from the presence of low-achieving classmates. This finding provides important policy implications for ability grouping of students in schools. With the help of a policy experiment I demonstrate that spreading out high ability students across classrooms is an efficient strategy to increase the achievement level of every student. In the third chapter, I introduce gender dimension into the analysis of peer effects and investigate the role of class gender composition on individual academic achievement. I employ two different identification strategies and find that large share of girls in a class facilitates academic progress of both boys and girls. While he average quality of girls is one of the determinants of own achievement, peer-to-peer interactions and improved discipline in a classroom, when more girls are present, also play an important role.