Economics Journal Articles

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...

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...

As the ACA Marketplaces face continued challenges with high premiums and limited insurer competition, there is significant interest in how policymakers can stabilize markets and control costs. We describe a unique set of active purchasing policies used by...

There is growing interest in market design using default rules and other "choice architecture” principles to steer consumers toward desirable outcomes. Using data from Massachusetts’ health insurance exchange, we study an “automatic retention” policy...

Insurance markets often feature consumer sorting along both an extensive margin (whether to buy) and an intensive margin (which plan to buy). We present a new graphical theoretical framework that extends the workhorse model to incorporate both selection...

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...

We analyze the evolution of health insurer costs in Massachusetts between 2010-2012, paying particular attention to changes in the composition of enrollees. This was a period in which Health Maintenance Organizations (HMOs) increasingly used physician...

Health insurers increasingly compete on their networks of medical providers. Using data from Massachusetts’ insurance exchange, I find substantial adverse selection against plans covering the most prestigious and expensive “star” hospitals. I highlight a...

Policymakers subsidizing health insurance often face uncertainty about future market prices. We study the implications of one policy response: linking subsidies to prices, to target a given post-subsidy premium. We show that these price-linked subsidies...