"The Evolution of Slums in Chile, 2000-2021" with Paul Gertler, Marco Gonzales-Navarro and Raimundo Undurraga.
Between 2011 and 2021, the number of slums in Chile increased by 36% and households residing in informal settlements more than doubled. Unlike many other places, Chile provides the location and extent of active slums for most of the last decade. Using that as a baseline, we identify areas ever covered by a slum regardless of when they were designated as a slum and obtain satellite images from those locations between 2002 and 2021. We built a panel that follows informal settlements before and after the government characterized them as slums. Over 90,000 satellite images were processed using Machine Learning and Human Processing Techniques to obtain data about the built environment inside and outside slums, including characteristics of the building footprints. We match this data with geocoded population census, household surveys, building permits, and public investments in slums. This research carries out three main analyses using this unique database. First, we show how slums' physical characteristics and demographics change over time. Slums are found to be dynamic, expanding rapidly and experiencing shifts in family structures. Second, we provide evidence on the relationship between slum expansion and local economic conditions in the area in which the slum is located. Slum growth is linked to higher rental prices and improved labor market outcomes, especially for low-skilled workers. Finally, we estimate the effect of two government interventions on slums’ physical and demographic characteristics. One intervention is population relocation, which aims to move slum households to other locations. The other is in-situ upgrading, which focuses on transforming the slum into a more formal neighborhood. We find that both interventions decrease slums’ building area and residential land, especially in slums targeted by the population removal strategy. However, building structures in the in-situ upgraded slums are more homogeneous, further apart, and more likely to have building permits, suggesting a significant improvement in housing quality. This research sheds light on the dynamics of slums in Chile and the impact of government interventions on these settlements.
"Eyes on the Street, Spatial Concentration of Retail Activity and Crime" with Stuart S. Rosenthal.
If spatial concentration of retail establishments amplifies the effect of “eyes on the street”, that should lower neighborhood crime rates and reduce investment in anti-crime measures, with benefits capitalized into higher retail rent. Data for New York City supports these predictions. In addition, comparisons between nighttime versus daytime crime, pre-pandemic versus COVID-19 lockdown, and different measures of spatial concentration shed light on mechanisms. Under plausible identifying conditions, increasing neighborhood concentration of retail outlets by one standard deviation reduces property crime and police stops by at least 8.5% and 11%, respectively, and causes retail rent to increase by at least 7.8%.
"Perceptions of Police Bias and the Location of Minority-Owned Establishment"
This paper considers whether perceptions of police bias can have lasting adverse effects on minority-owned businesses even after evidence of police misconduct has diminished. Customers and workers are discouraged from conducting business in areas where they might feel unsafe. That in turn may hurt the profitability of minority-owned businesses in neighborhoods where concerns about police behavior are prevalent, reducing the presence of minority-owned establishments and their potential to thrive in such locations. Using data on police stops from the Stop-Question-Frisk policy in New York City, I find that minority-owned businesses are less present and exhibit higher failure rates in neighborhoods where perceptions of police bias are likely to be more pronounced. Differences in patterns by industry provide suggestive evidence that minority customers and workers are discouraged from locations where police behavior against minorities can be perceived as biased.