Asymmetric information in health insurance: evidence from the National Medical Expenditure Survey.

Adverse selection is perceived to be a major source of market failure in insurance markets. There is little empirical evidence on the extent of the problem. We estimate a structural model of health insurance and health care choices using data on single individuals from the NMES. A robust prediction of adverse-selection models is that riskier types buy more coverage and, on average, end up using more care. We test for unobservables linking health insurance status and health care consumption. We find no evidence of informational asymmetries.

An examination of flexible spending accounts.

This paper develops a framework for analyzing flexible spending account (FSA) participation and usage. We explore patterns of FSA usage using data from a benefits firm for 1996 including an examination of types of FSA expenditures and their timing. We estimate some simple econometric models of the participation decision and also the decision of how much to put into an FSA. Several pieces of evidence suggest that much of an FSA election amount is based on foreknowledge of expenditures. We also find that participants tend to spend their election amount early, thus obtaining an interest-free loan.