Self-control devices, such as rehabilitation programs, group commitment, and informal fines, can make time-inconsistent smokers better off. Health economists have used this result to argue in favor of cigarette taxes that restrain smoking. However, taxes alone are not Pareto-improving overall,...

The classic theory of moral hazard concerns the insurance of a single good and predicts that co-insurance is larger when the elasticity of demand is higher and when small risks are insured. We extend this analysis to the insurance of multiple goods; for example, the simultaneous insurance of...