NBER Working Papers by Edward C. Norton

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.

Previous estimates on the association between body weight and wages in the literature have been contingent on education and occupation. This paper examines the direct effect of BMI on wages and the indirect effects operating through education and occupation choice, particularly for late-teen BMI and adult wages. Using the National Longitudinal Survey of Youth 1979 data, we show that education is the main pathway for the indirect BMI wage penalty. The total BMI wage penalty is underestimated by 18% for women without including those indirect effects. Whereas for men there is no statistically significant direct BMI wage penalty, we do observe a small indirect wage penalty through education.

There is much debate about whether the Medicare Prescription Drug Bill -- the greatest expansion of Medicare benefits since its creation in 1965 -- will improve the health of elderly Americans, and how much it will cost. We model how insurance affects medical care utilization, and subsequently, health outcomes over time in a dynamic model with correlated errors. Longitudinal individual-level data from the 1992-1998 Medicare Current Beneficiary Survey provide estimates of these effects. Simulations over five years show that expanding prescription drug coverage would increase drug expenditures by between 12% and 17%. However, other health care expenditures would only increase slightly, and the mortality rate would improve.