Since 2012, institutional investors entered the single-family rental market in areas that subsequently experienced high rent and house price growth. To determine the impact of institutional investors on the housing market, this paper estimates a structural model where institutional investor landlords benefit from economies of scale and market power. Overall, institutional investor entry resulted in a tradeoff. Renters benefited from lower rents because institutional investors increased the rental supply by 0.52 homes for each home they purchased. This expansion occurred because economies of scale outweighed the incentive to use market power to decrease supply. However, prospective homeowners had a harder time buying homes: Homeownership decreased by 0.21 homes for each home purchased, and institutional investors caused 23% of the observed price increase in their top decile of markets. Supply responses dampened these impacts. These findings show that economies of scale, not market power, are the driving mechanism behind institutional investor impact in the single-family rental market.

Low property taxes amplify lock-in effects for elderly homeowners, limiting housing access for young families. Higher property taxes function as "embedded leverage reducing required down payments through a capitalization effect and enabling greater homeownership among younger households. Our overlapping generations model shows that raising California's property taxes to Texas levels would increase homeownership by six percentage points and young household ownership by eight percentage points. Conversely, higher capital gains taxes worsen lock-in effects and reduce young homeownership. Asset taxes can effectively reallocate housing to higher-valuation households when financial constraints exist, providing an independent justification for property taxation policies.

We examine the determinants of COVID-19 risk exposure in the context of the initial wave in New York City. In the first wave of the pandemic, out-of-home activity and household crowding were strongly associated with hospitalization at an individual level. After mass layoffs and shelter in place restrictions, out-of-home mobility decreased in importance for the risk of COVID-19 hospitalization, while the household crowding channel remained important. A larger share of individuals in crowded housing or with high measures of out-of-home mobility were Black, Hispanic, and lower-income—which contributed to disparities in disease risk. We conclude that structural socio-economic inequalities helped determine the cross-section of COVID-19 risk exposure in urban areas.

We document large-scale urban flight in the United States during the COVID-19 pandemic. Regions that saw migrant influx experienced greater subsequent new COVID-19 cases, linking urban flight (as a disease vector) and coronavirus spread in destination areas. Urban residents fled to socially connected areas, consistent with the theory that individuals sheltered with friends and family, or in second homes. Populations that fled were disproportionately younger, whiter, and wealthier. The association between migration and subsequent new cases persists when instrumenting for migration with social networks.

Press: The New York Times Upshot · Bloomberg · Forbes · Marginal Revolution

We investigate the role of demographic differences in mobility in explaining disparities in COVID-19 outcomes in New York City. We find: 1) New York City residents in richer neighborhoods are substantially more likely to flee the city, 2) Low-income, Black, and Hispanic neighborhoods exhibit more work activity during the day, and 3) these neighborhoods also exhibit less sheltering in place activity during non-work hours. Measured disparities in COVID-19 cases are attenuated after accounting for these mobility responses. Our results point to important inequities in access to sheltering options during pandemics within cities.