This article describes the anatomy of health insurance. It begins by considering the optimal design of health insurance policies. Such policies must make tradeoffs appropriately between risk sharing on the one hand and agency problems such as moral hazard (the incentive of people to seek more...

In the United States, households obtain health insurance through distinct market segments. We explore the economics of this segmentation by comparing coverage provided through small employers versus the individual marketplace. Using data from Oregon, we find households with group coverage spend...

We study how inertia interacts with market power and adverse selection in managed competition health insurance markets. We use consumer-level data to estimate a model of the California ACA exchange, in which four firms dominate the market and risk adjustment is in place to manage selection. We...

We study the Medicare Part D prescription drug insurance program as a bellwether for designs of private, non-mandatory health insurance markets that control adverse selection and assure adequate access and coverage. We model Part D enrollment and plan choice assuming a discrete dynamic decision...

Individual, personalized genetic information is increasingly available, leading to the possibility of greater adverse selection over time, particularly in individual-payer insurance markets; this selection could impact the viability of these markets. We use data on individuals at risk for...

This study assesses the factors influencing the movement of people across health plans. We distinguish three types of cost-related transitions: adverse selection, the movement of the less healthy to more generous plans; adverse retention, the tendency for people to stay where they are when they...

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....

The United States and other nations rely on consumer choice and price competition among competing health plans to allocate resources in the health sector. A great deal of research has examined the efficiency consequences of adverse selection in health insurance markets, less attention has been...

The obesity rate in the United States has risen significantly in the past few decades. While a number of economic causes for the rise in obesity have been explored, little attention has been on the role of health insurance per se. This paper examines obesity in the context of a model where...

During the last two decades, the treatment of infertility has improved dramatically. These treatments, however, are expensive and rarely covered by insurance, leading many states to adopt regulations mandating that health insurers cover them. In this paper, we explore the effects of benefit...