Previous empirical studies have typically uncovered little evidence that police reduce crime. One problem with those studies is a failure to adequately deal with the simultaneity between police and crime: while police may or may not reduce crime, there is little doubt that expenditures on police...

Donohue and Levitt (2001) present a number of analyses that suggest a causal link between legalized abortion and reductions in crime almost two decades later when the cohorts exposed to legalized abortion reach their peak crime years. Joyce (2003) challenges that finding. In this paper, we...

A wide range of social indicators turned sharply negative for Blacks in the late 1980s and began to rebound roughly a decade later. We explore whether the rise and fall of crack cocaine can explain these patterns. Absent a direct measure of crack cocaine%u2019s prevalence, we construct an index...

The number of prisoners incarcerated on drug-related offenses rose fifteen-fold between 1980 and 2000. This paper provides the first systematic empirical analysis of the implications of that dramatic shift in public policy. We show that the increase in drug prisoners led to reductions in...

On tests of intelligence, Blacks systematically score worse than Whites, whereas Asians frequently outperform Whites. Some have argued that genetic differences across races account for the gap. Using a newly available nationally representative data set that includes a test of mental function for...

This paper demonstrates that rising crime rates in cities are correlated with city depopulation. Instrumental variables estimates, using measures of the certainty and severity of a state?s criminal justice system as instruments for city crime rates, imply that the direction of causality runs...

Profit maximizing behavior on the part of firms is a fundamental, but rarely tested, assumption of economics. In this paper, I analyze the decisions made by an MIT trained economist running a company that delivers bagels and donuts. The simplicity and transparency of the business (e.g. marginal...

Previous studies of the impact of changes in prisoner populations on crime rates have failed to adequately control for the simultaneity between those two variables. While increases in the number of prisoners are likely to reduce crime, rising crime rates also translate into larger prison...

Productivity improvements within establishments (e.g., factories, mines, or retail stores) are an important source of aggregate productivity growth. Past research has documented that learning by doing-productivity improvements that occur in concert with production increases-is one source of such...

The minimax argument represents game theory in its most elegant form: simple but with stark predictions. Although some of these predictions have been met with reasonable success in the field, experimental data have generally not provided results close to the theoretical predictions. In a...