Health plans for the poor increasingly limit access to specialty hospitals. We investigate the role of adverse selection in generating this equilibrium among private plans in Medicaid. Studying a network change, we find that covering a top cancer hospital causes severe adverse selection,...

Subsidies in many health insurance programs depend on prices set by competing insurers -- as prices rise, so do subsidies. We study the economics of these "price-linked" subsidies compared to "fixed" subsidies set independently of market prices. We show that price-linked subsidies weaken price...

How much are low-income individuals willing to pay for health insurance, and what are the implications for insurance markets? Using administrative data from Massachusetts' subsidized insurance exchange, we exploit discontinuities in the subsidy schedule to estimate willingness to pay and costs...

The United States spends substantially more on health care than most developed countries, yet leaves a greater share of the population uninsured. We suggest that incremental insurance expansions focused on addressing market failures will propagate inefficiencies and are not likely to facilitate...

Incomplete health insurance enrollment is a persistent U.S. challenge despite large subsidies. We ask whether hassles built into enrollment systems matter for insurance take-up and targeting. Studying removal of an auto-enrollment policy, we find that a small hassle – a requirement to actively...