We argue that the key impediment to accurate measurement of the effect of police on crime is not necessarily simultaneity bias, but bias due to mismeasurement of police. Using a new panel data set on crime in medium to large U.S. cities over 1960- 2010, we obtain measurement error corrected...

This paper examines changes in individual real incomes in South Africa between 1995 and 2000. We document substantial declines--on the order of 40%--in real incomes for both men and women. The brunt of the income decline appears to have been shouldered by the young and the non-white. We argue...

Using over eight trillion observations of market data, we use a regression discontinuity design to analyze the effect of increasing the minimum price variation (MPV) for quoting equity securities in light of recent proposals to increase the MPV from $0.01 to $0.05. We show that a larger MPV...

We use new timestamp data from the two Securities Information Processors (SIPs) to examine SIP reporting latencies for quote and trade reports. Reporting latencies average 1.13 milliseconds for quotes and 22.84 milliseconds for trades. Despite these latencies, liquidity-taking orders gain on...

Arguably the most aggressive affirmative action program ever implemented in the United States was a series of court-ordered racial hiring quotas imposed on municipal police departments. My best estimate of the effect of court-ordered affirmative action on workforce composition is a 14 percentage...

Standard sufficient conditions for identification in the regression discontinuity design are continuity of the conditional expectation of counterfactual outcomes in the running variable. These continuity assumptions may not be plausible if agents are able to manipulate the running variable. This...

This paper uses age-at-school-entry policies to identify the effect of female education on fertility and infant health. We focus on sharp contrasts in schooling, fertility, and infant health between women born just before and after the school entry date. School entry policies affect female...

Economic theory predicts that increasing the severity of punishments will deter criminal behavior by raising the expected price of committing crime. This implicit price can be substantially raised by making prison sentences longer, but only if offenders' discount rates are relatively low. We use...

Objective: The increasing availability of large administrative datasets has led to a particularly exciting innovation in criminal justice research, that of the “low-cost” randomized trial in which administrative data are used to measure outcomes in lieu of costly primary data collection. In...

We report the first empirical estimate of the race-specific effects of larger police forces in the United States. Each additional police officer abates approximately 0.1 homicides. In per capita terms, effects are twice as large for Black versus white victims. At the same time, larger police...