Aaron Chalfin

University of Pennsylvania

E-Mail: EmailAddress: hidden: you can email any NBER-related person as first underscore last at nber dot org
Institutional Affiliation: University of Pennsylvania

NBER Working Papers and Publications

July 2019The Minimum Legal Drinking Age and Crime Victimization
with Benjamin Hansen, Rachel Ryley: w26051
For every crime there is a victim. However nearly all studies in the economics of crime have focused the causal determinants of criminality. We present novel evidence on the causal determinants of victimization, focusing on legal access to alcohol. The social costs of alcohol use and abuse are sizable and well-documented. We find criminal victimization for both violent and property crimes increases noticeably at age 21. Effects are not present at other birthdays and do not appear to be driven by a birth-day "celebration effect." The effects are particularly large for sexual assaults, especially those that occur in public locations. Our results suggest prior research which has focused on criminality has understated the true social costs associated with increased access to alcohol.
May 2019Reducing Crime Through Environmental Design: Evidence from a Randomized Experiment of Street Lighting in New York City
with Benjamin Hansen, Jason Lerner, Lucie Parker: w25798
This paper offers experimental evidence that crime can be successfully reduced by changing the situational environment that potential victims and offenders face. We focus on a ubiquitous but surprisingly understudied feature of the urban landscape – street lighting – and report the first experimental evidence on the effect of street lighting on crime. Through a unique public partnership in New York City, temporary streetlights were randomly allocated to public housing developments from March through August 2016. We find evidence that communities that were assigned more lighting experienced sizable reductions in crime. After accounting for potential spatial spillovers, we find that the provision of street lights led, at a minimum, to a 36 percent reduction in nighttime outdoor index crimes.
March 2019Administrative Data Linking and Statistical Power Problems in Randomized Experiments
with Sarah Tahamont, Zubin Jelveh, Shi Yan, Benjamin Hansen: w25657
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 this paper, we point out that randomized experiments that make use of administrative data have an unfortunate consequence: the destruction of statistical power. Linking data from an experimental intervention to administrative records that track outcomes of interest typically requires matching datasets without a common unique identifier. In order to minimize mistaken linkages, researchers will often use “exact matching” (retaining an individual only if all their demographic variables match exactly in tw...
February 2013The Effect of Police on Crime: New Evidence from U.S. Cities, 1960-2010
with Justin McCrary: w18815
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 estimates of the police elasticity of the cost-weighted sum of crimes of roughly -0.5. The estimates confirm a controversial finding from the previous literature that police reduce violent crime more so than property crime.
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