Standard Medicare Part D drug insurance provides limited coverage in a ``donut hole'' region, making the purchase problem dynamic. We develop a discontinuity-based test for myopia using enrollees who arrived near the coverage gap early in the year. We find that there are fewer and cheaper...

Coal mining is a dangerous occupation where safety is an important output. Fatalities and disasters may change future accident costs at or near a mine. We use this variation to understand the tradeoffs between mineral output and safety. We find that government inspections and penalties increase...

The objective of this study is to estimate the effects of competition for both Medicare and HMO patients on the quality decisions of hospitals in Southern California. We use discharge data from the State of California for the period 1989-1993. The outcome variables are the risk-adjusted hospital...