While conducting empirical work, researchers sometimes observe changes in outcomes before adoption of a new policy. The conventional diagnosis is that treatment is endogenous. This observation is also consistent, however, with anticipation effects that arise naturally out of many theoretical...

SARS struck Taiwan in 2003, causing a national crisis. Many people feared that SARS would spread through the health care system, and outpatient visits fell by more than 30% in the course of a few weeks. We examine how both public information and the behavior and opinions of peers contributed to...

Economists think of medical innovation as a valuable but risky good, producing health benefits but increasing financial risk. This perspective overlooks how innovation can lower physical risks borne by healthy patients facing the prospect of future disease. We present an alternative framework...

In a complex economy, production is vertical and crosses jurisdictional lines. Goods are often produced by an upstream national or global firm and improved or distributed by local firms downstream. In this context, heightened products liability may have unintended consequences on product sales...

Self-selection can bias estimates of treatment effects from randomized experiments if one is interested in extrapolating results to the general population. This paper notes that there is an isomorphism between the Roy model for the sorting of workers into sectors and the decision of subjects to...

A medical treatment is said to have placebo effects if patients who are optimistic about the treatment respond better to the treatment. This paper proposes a simple test for placebo effects. Instead of comparing the treatment and control arms of a single trial, one should compare the treatment...