We specify and estimate a general health equation. Among the determinants of health, we include employment status, alcohol use, and cigarette use. Non linear instrumental techniques are employed to control for any possible endogeneity of these variables.

Not withstanding the equivalence in static framework between an ad-valorem and a specific sale tax, this paper shows in the dynamic Hotelling model for an exhaustible resource that the ad valorem tax is definitely welfare-superior to the specific tax.