The cost of efforts to expand health insurance coverage to the currently uninsured increases when people who would otherwise purchase private insurance obtain subsidized public coverage. Legislators are increasingly interested in mechanisms that target insurance benefits to those who need them...

We compare healthcare spending in public and private Medicare using newly available claims data from Medicare Advantage (MA) insurers. MA insurer revenues are 30 percent higher than their healthcare spending. Healthcare spending is 25 percent lower for MA enrollees than for enrollees in...

A health insurer's Medical Loss Ratio (MLR) is the share of premiums spent on medical claims. The Affordable Care Act introduced minimum MLR provisions for all health insurance sold in fully-insured commercial markets, thereby capping insurer profit margins, but not levels. While intended to...

Despite the popularity of pay-for-performance (P4P) among health policymakers and private insurers as a tool for improving quality of care, there is little empirical basis for its effectiveness. We use data from published performance reports of physician medical groups contracting with a large...

Prices in government and employer-sponsored health insurance markets only partially reflect insurers' expected costs of coverage for different enrollees. This can create inefficient distortions when consumers self-select into plans. We develop a simple model to study this problem and estimate it...

This paper provides empirical evidence of Medicaid crowd out of demand for private long-term care insurance. Using data on the near- and young-elderly in the Health and Retirement Survey, our central estimate suggests that a $10,000 decrease in the level of assets an individual can keep while...

Most health insurance uses cost-sharing to reduce excess utilization. Supplemental insurance can blunt the impact of this cost-sharing, increasing utilization and exerting a negative externality on the primary insurer. This paper estimates the effect of private Medigap supplemental insurance on...

Standard theory suggests that optimal consumer cost-sharing in health insurance increases with the price elasticity of demand, yet publicly-provided drug coverage typically involves uniform cost-sharing across drugs. We investigate how private drug plans set cost-sharing in the context of...

This paper investigates consumer switching costs in the context of health insurance markets, where adverse selection is a potential concern. Though previous work has studied these phenomena in isolation, they interact in a way that directly impacts market outcomes and consumer welfare. Our...

I take advantage of regulatory and pricing dynamics in Medicare Part D to empirically explore interactions among adverse selection, switching costs, and regulation. I first document novel evidence of adverse selection and switching costs within Part D using detailed administrative data. I then...