Standardization of complex products is touted as improving consumer decisions and intensifying price competition, but evidence on standardization is limited. We examine a natural experiment: the standardization of health insurance plans on the Massachusetts Health Insurance Exchange....

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 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....

In this paper we explore the possibility that individuals may select insurance coverage in part based on their anticipated behavioral response to the insurance contract. Such "selection on moral hazard" can have important implications for attempts to combat either selection or moral hazard. We...