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...

We analyze Medicare Part D's net effect on elderly out-of-pocket (OOP) costs and use of prescription drugs using a dataset containing 1.4 billion prescription records from Wolters Kluwer Health (WKH). These data span the period December 2004-December 2007 and include pharmacy customers whose age...

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...

This study provides a national analysis of how the 2014 Affordable Care Act (ACA) Medicaid expansions have affected aggregate prescription drug utilization. Given the prominent role of prescription medications in the management of chronic conditions, as well as the high prevalence of unmet...

The design of Medicare Part D causes most Medicare beneficiaries to receive fragmented health insurance, whereby prescription drugs and other medical care are covered by separate insurance plans. Fragmentation of insurance plans is potentially inefficient since separate insurers maximize profits...

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,"...

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....

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...