@techreport{NBERw15864,
 title = "Estimation of a Dynamic Model of Weight",
 author = "Shu Wen Ng and Edward C. Norton and David K. Guilkey and Barry M. Popkin",
 institution = "National Bureau of Economic Research",
 type = "Working Paper",
 series = "Working Paper Series",
 number = "15864",
 year = "2010",
 month = "April",
 URL = "http://www.nber.org/papers/w15864",
 abstract = {The ongoing debate about the economic causes of obesity has focused on the changing relative prices of diet and exercise. This paper uses a model that explicitly includes time and spatially varying community-level urbanicity and price measures as instruments to obtain statistically correct measures for the endogenous effects of diet, physical activity, drinking, and smoking on weight. We apply a dynamic panel system GMM estimation model to longitudinal (1991–2006) data from China to model weight and find that among adult men in China, about 6.1% of weight gain was due to declines in physical activity and 2.9-3.8% was due to dietary changes over this period. In the long run, physical activity can account for around 6.9% of weight gain, while diet can account for 3.2-4.2% of weight gain.},
}