Do peers affect childhood obesity outcomes? Peer‐effect analysis in public schools
本研究使用工具变量法分析公立学校中同伴体重对儿童BMI z分数的影响，发现影响虽统计显著但实际效果很小。
Abstract This study investigates whether obese peers are a contributing factor in childhood body‐weight outcomes. Using an instrumental variables method on exogenously assigned peers (i.e., new peers), we find that the weight of peers within the same grade and school significantly impacts body mass index (BMI) z‐score of an individual student. The size of the peer effect, however, is negligible. We find no evidence of interaction between newly assigned peer groups prior to assignment. Furthermore, the obese peers variable is significant only for those peers with whom a student interacts.