We study optimal risk adjustment in imperfectly competitive health insurance markets when high-risk consumers are less likely to switch insurer than low-risk consumers. First, we find that insurers still have an incentive to select even if risk adjustment perfectly corrects for cost differences...

International surveys reveal wide differences between the views held in different countries concerning the causes of wealth or poverty and the extent to which people are responsible for their own fate. At the same time, social ethnographies and experiments by psychologists demonstrate...

I develop a model of ideologies as collectively sustained (yet individually rational) distortions in beliefs concerning the proper scope of governments versus markets. In processing and interpreting signals of the efficacy of public and market provision of education, health insurance, pensions,...

I develop a model of (individually rational) collective reality denial in groups, organizations and markets. Whether participants' tendencies toward wishful thinking reinforce or dampen each other is shown to hinge on a simple and novel mechanism. When an agent can expect to benefit from other's...

The hosting and bidding for the Olympic Games is a natural experiment to test for anticipation effects in macroeconomics. We examine these effects using panel data for 184 countries during the period 1950-2006. We find that hosting the Games generates positive investment, consumption, and output...

There is renewed interest in ways to enhance secondary education, especially among disadvantaged students. This study evaluates the short-term effects of a remedial education programme that provided additional instruction to under-performing high school students in Israel. The programme targeted...

In this paper we test for the theory of deterrence. We exploit the natural experiment provided by the Collective Clemency Bill passed by the Italian Parliament in July 2006. As a consequence of the provisions of the bill, expected punishment to former inmates recommitting a crime can be...

This paper analyzes a recent ballot in which two virtually identical popular initiatives, both demanding a decrease in the legal age of retirement in Switzerland, led to differences in approval rates of nearly seven percentage points. Based on this unique natural experiment, the existence of...

We examine the relationship between education and mortality in a young population of Italian males. In 1981 several cohorts of young men from specific southern towns were unexpectedly exempted from compulsory military service after a major quake hit the region. Comparisons of exempt cohorts from...

We study the response of regional employment and nominal wages to trade liberalization, exploiting the natural experiment provided by the opening of Central and Eastern European markets after the fall of the Iron Curtain in 1990. Using data for Austrian municipalities, we examine differential...