A ubiquitous form of government intervention in insurance markets is to provide compulsory, but partial, public insurance coverage and to allow voluntary purchases of supplementary insurance on the private market. Yet we know little about the effects of such programs on total insurance coverage...

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...

Standard theories of insurance, dating from Rothschild and Stiglitz (1976), stress the role of adverse selection in explaining the decision to purchase insurance. In these models, higher risk people buy full or near-full insurance, while lower risk people buy less complete coverage, if they buy...

Rewarding inventors with inefficient monopoly power has long been regarded as the price of encouraging innovation. Public prescription drug insurance escapes that trade-off and achieves an elusive goal: lowering static deadweight loss, while simultaneously encouraging dynamic investments in...

The federal-state Medicaid program insures 43 million people for virtually all of the prescription drugs approved by the FDA. To determine the price that it will pay for a drug treatment, the government uses the average price in the private sector for that same drug. Assuming that Medicaid...

We study the demand response to non-linear price schedules using data on insurance contracts and prescription drug purchases in Medicare Part D. Consistent with a static response of drug use to price, we document bunching of annual drug spending as individuals enter the famous "donut hole,"...

Generic drugs comprise an increasing share of total prescriptions dispensed in the U.S., rising from nearly 50 percent in 1999 to 75 percent in 2009. The generic drug market has typically been viewed at the wholesale level as a competitive market with price approaching marginal costs. However,...

We show how standard consumer and producer theory can be used to estimate welfare in insurance markets with selection. The key observation is that the same price variation needed to identify the demand curve also identifies how costs vary as market participants endogenously respond to price....

On January 1, 2006, the federal government began providing insurance coverage for Medicare recipients' prescription drug expenditures through a new program known as Medicare Part D. Rather than setting pharmaceutical prices itself, the government contracted with private insurance plans to...

A large literature in empirical public finance relies on "bunching" to identify a behavioral response to non-linear incentives and to translate this response into an economic object to be used counterfactually. We conduct this type of analysis in the context of prescription drug insurance for...