Working Papers

with M. Keith Chen, Katherine L. Christensen, Elicia John, and Emily Owens

Accepted, The Review of Economics and Statistics 

Abstract: Research on policing has focused on documented actions such as stops and arrests—less is known about patrols and presence. We map the neighborhood movement of nearly ten thousand officers across 21 of America’s largest cities using anonymized smartphone data. Police spend 0.27% more time in neighborhoods for each percentage point increase in Black residents. This neighborhood-level disparity persists after controlling for density, socioeconomic, and crime-driven demand for policing, and is lower in cities with more Black police supervisors (but not officers). Patterns of police presence statistically explain 55% of the higher arrest rate in more Black neighborhoods.

with M. Keith Chen, Malena de la Fuente, Ryne Rohla, and Elisa F. Long

Abstract: Accurately estimating the effectiveness of stay-at-home orders (SHOs) on reducing social contact and disease spread is crucial for mitigating pandemics. Leveraging individual-level location data for 10 million smartphones, we observe that by April 30th—when nine in ten Americans were under a SHO—daily movement had fallen 70% from pre-COVID levels. Onequarter of this decline is causally attributable to SHOs, with wide demographic differences in compliance, most notably by political affiliation. Likely Trump voters reduce movement by 9% following a local SHO, compared to a 21% reduction among their Clinton-voting neighbors, who face similar exposure risks and identical government orders. Linking social distancing behavior with an epidemic model, we estimate that reductions in movement have causally reduced SARSCoV-2 transmission rates by 49%.

with Jaimie W. Lien and Jie Zheng

Abstract: Although contests are recognized theoretically as a highly effective method of motivation, the competitive nature of contests may generate unintended negative effects on social interactions in more general settings beyond contests. Using a laboratory experiment of real effort tasks with treatments varying by compensation schemes (all-pay auction contest, Tullock contest, proportional prize contest, and piece rate payment scheme), we test the relative effect of contest formats on cooperation in social dilemma games. In comparison to a hypothesized ranking of compensation schemes based on the correspondence between effort exerted and reward received (‘Effort Correspondence’), our results provide relatively stronger support for an alternative hypothesis that cooperative behavior after a competition is tied to the potential for obtaining ‘fair’ payoff outcomes within the contest (‘Chance for Fair Division’). Our random re-matching experimental design ensures that our findings do not result from subjects’ rivalry towards specific competitors, but rather represents a more fundamental shift in prosocial attitude. The results have managerial consequences for structuring incentives in the workplace when a combination of competition and cooperation is necessary among workers.