Abstract: The delayed response of law enforcement to calls for service has become a hot button issue when evaluating police department performance. While it is often assumed that faster response times could play an important role in quelling potentially violent incidents, there is no empirical evidence to support this claim. In this paper, we measure the effect of police response time on the likelihood that an incident will result in an injury. To overcome the endogeneity of more severe calls being assigned higher priority, which requires a faster response, we take several steps. First, we focus on the subset of calls for service categorized as ``Major Disturbance-Violence" that all receive the same priority level. Second, we instrument for police response time with the number of vehicles within a 2.5-mile radius of the incident at the time it is received by the call center. When controlling for beat, month, and time-of-day fixed effects, this instrumenting strategy allows us to take advantage of the geographical constraints faced by a dispatcher when assigning officers to an incident. In contrast to the OLS estimates, our two-stage least squares analysis establishes a strong causal relationship whereby increasing response time increases the likelihood that an incident results in an injury. The effect is concentrated among female victims, suggesting that faster response time could potentially play an important role in reducing injuries related to domestic violence.
Abstract: We study the effects of public pension systems on the retirement timing of older workers and, in turn, the health consequences of delaying retirement by those workers. Causal inference relies on a social security reform in Israel that shifted payments from husbands to their (non-working) wives, thereby substantially reducing the implied tax on the husband’s employment while keeping overall household wealth constant. Using administrative social security data, we estimate extensive-margin labor supply elasticities w.r.t. the average net-of-tax rate of about 0.43 for men over 65. Using the reform to instrument for employment, we find that working an additional full year at old age decreases longevity. This mortality effect occurs after age 75 and is driven by workers holding blue-collar jobs. Finally, we evaluate the effect of the reform on earnings. The results imply a small value for an additional year of life, suggesting that workers underestimate the health cost of employment at older ages.
Abstract: This paper estimates the impact of police presence on crime using a unique database that tracks the exact location of Dallas Police Department patrol cars throughout 2009. To address the concern that officer location is often driven by crime, my instrument exploits police responses to calls outside of their allocated coverage beat. This variable provides a plausible shift in police presence within the abandoned beat that is driven by the police goal of minimizing response times. I find that a 10 percent decrease in police presence at that location results in a 7 percent increase in crime. This result sheds light on the black box of policing and crime and suggests that routine changes in police patrol can significantly impact criminal behavior.. JEL Codes: D29, K42.
Abstract: Existing studies examining the crime impacts of stop, question, and frisks (SQFs) have focused on large geographic areas. The current study aims to address the limitations of prior studies by exploring the impact of SQFs on daily and weekly crime incidents in NYC at a micro-geographic level. The findings suggest that SQFs produce a significant yet modest deterrent effect on crime.
Abstract: This paper capitalizes on a unique situation in Israel where car insurance coverage is often distributed as a benefit by employers. In our sample, employer-determined coverage resulted in an average $235 discount in accident costs. Using instrumental variable analysis on data provided by an insurance firm in Israel (2001-2008), we find that each $100 reduction in accident costs results in a 1.7 percentage point increase in the probability of an accident. At an average accident rate of 16.3 percent, this 10 percent increase in auto accidents can be interpreted as the effect of moral hazard on car accidents. (JEL: D82, G22)
Abstract: Does providing consumers with information about discounts, help them realize more savings? We address this question using data from a field experiment on a website that offers purchase and delivery from a local supermarket chain in the U.S. Our results illustrate the difficulty in using information provision to steer shoppers towards cheaper alternatives (of equal or higher quality than their substitutes) when consumers shop for multiple products with changing prices. We find that providing (treatment) shoppers with promotional information on sale categories increases the probability of purchasing within the category. This effect is driven by an increase in purchasing rates for both the reduced priced items and regularly priced alternatives. Our analysis focuses on understanding how item placement, promotional information, and the way promotional information is diplayed play a role in affecting consumer surplus. Keywords: Limited attention, Salience, Information processing, Supermarket shopping.
Works in Progress - Draft Coming Soon
"The Accident Implications of a Company Car Benefit"
Abstract: Company cars that include free fuel, insurance and maintenance have become a staple employee benefit in many Israeli and European companies. Moral hazard would suggest that the benefits associated with these cars would result in lower driving care and higher accident rates. However, it is often argued that drivers receiving this benefit face longer commutes and/or a more difficult work schedule which would result in an increased rate of car accidents regardless of a moral hazard effect. Using a difference in differences strategy, we analyze the impact of a legislative change that doubled the monthly tax rate on company cars in Israel (an annual increase in costs of about $3,500). We find evidence that this increase in company car costs resulted in an 11% decrease in the probability of an accident for company car type drivers.
"The Swap & Be-Healthy & Product Promotion Supermarket Shopping Interventions" (with Kfir Eliaz, Neil Thakral, and Mathias Wagner Barlose)
Abstract: This project analyzes data from two large-scale randomized controlled experiments run on roughly 35,000 shoppers on an online grocery platform. During the four-month intervention period of the Swap and Be Healthy experiment, 50 percent of the users were randomly allocated to the Swap and be Healthy treatment nudge. When these treatment shoppers added a less healthy product to their basket, a popup appeared with the option to swap to a healthier substitute (lower fat, less salt, etc.) with the click on an icon. During the four-month intervention period of the Product Promotion experiment, 50 percent of shoppers were randomly allocated to viewing a banner of on-sale junk-food products, and the remaining 50 percent were allocated to viewing a banner of on-sale non-food products. Within each of these groups, half of the shoppers were randomly allocated to viewing the banner at the beginning of their shopping trip, while the other half viewed the same banner at the end of their shopping trip. We examine how exposure to these interventions influence shopping decisions, and the extent to which the effects persist over time after the intervention period ends. Our data provide an opportunity to test both what types of consumers are most impacted by the interventions and estimate how the time (within the shopping trip) at which a consumer considers purchasing an unhealthy item impacts their responsiveness to information and prices.