We develop a test for adverse selection and use it to examine private health insurance markets. In contrast to earlier papers that consider a purely private system or a system in which private insurance supplements a public system, we focus our attention on a system where privately funded health...

When health plans compete under adverse selection, the competitive equilibrium set of contracts is unique. However, the allocation of these contracts among health plans is undetermined. We show that three health plans suffice to sustain an equilibrium where each health plan offers a single...

When health plans compete under adverse selection, the competitive equilibrium set of contracts is unique. However, the allocation of these contracts among health plans is undetermined. We show that three health plans suffice to sustain an equilibrium where each health plan offers a single...