Despite the urgent public health implications, relatively little is yet known about the effect of peers on adolescent weight gain. We describe trends and features of adolescent BMI in a nationally representative dataset and document correlations in weight gain among peers. We find strong...

Recent research in the New England Journal of Medicine (NEJM) purports to show the existence of peer effects in the spread of obesity. Using a dataset of 5124 residents from Framingham, Massachusetts spanning the years 1971 to 2003, the authors show correlations between own weight gain and...

The potential influence of peers and social networks on individual outcomes is important to a variety of educational policy debates including school vouchers, special education, middle school grade configurations and tracking. Researchers usually address the identification problems associated...

We employ a standard identification strategy from the peer effects literature to investigate the importance of network definitions in estimation of endogenous peer effects. We use detailed information on friends in the Adolescent Longitudinal Health Survey (Add Health) to construct two network...