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...

Insurance induces a well-known tradeoff between the welfare gains from risk protection and the welfare losses from moral hazard. Empirical work traditionally estimates each side of the tradeoff separately, potentially yielding mutually inconsistent results. I develop a nonlinear budget set model...

This paper shows that, except in certain limiting cases, competitive equilibrium with moral hazard is constrained inefficient. The first section compares the competitive equilibrium and the constrained social optimum in a fairly general model, and identifies types of market failure. Each of the...

We analyze data from the Health and Retirement Study on senior citizens' take-up of Medicare Part D. Take-up among those without drug coverage in 2004 was high; about fifty to sixty percent of this group have Part D coverage in 2006. Only seven percent of senior citizens lack drug coverage in...

Neoclassical and psychological models of consumer behavior often make divergent predictions for the welfare effects of paternalistic policies, leaving wide scope for researchers' choice of a model to influence their policy conclusions. We develop a framework to reduce this model uncertainty and...

In many markets insurers are barred from price discrimination based on consumer characteristics like age, gender, and medical history. In this paper, I build on a recent literature to show why such policies are inefficient if consumers differ in their willingness-to-pay for insurance conditional...

This paper examines the economic rationale of affordability exemptions in the context of a health insurance mandate. On its face, an affordability exemption makes little sense-- it exempts people from purchasing a good that policymakers believe benefits them. I provide an economic definition of...

Basic economic theory suggests that health insurance coverage may cause a reduction in prevention activities, but empirical studies have yet to provide much evidence to support this prediction. However, in other insurance contexts that involve adverse health events, evidence of ex ante moral...

The obesity rate in the United States has risen significantly in the past few decades. While a number of economic causes for the rise in obesity have been explored, little attention has been on the role of health insurance per se. This paper examines obesity in the context of a model where...

We examine the effect of gaining prescription drug insurance as a result of Medicare Part D on use of prescription drugs, use of other medical services, and health for a nationally representative sample of Medicare beneficiaries. Given the heightened importance of prescription drugs for those...