Research

Abstract: Neighborhoods shape economic opportunity, yet access to high-opportunity areas remains limited. Can cities expand access at scale without discouraging development or triggering displacement? I study inclusionary zoning (IZ), a policy that requires developers to provide affordable units within new residential projects, typically in exchange for density bonuses. Using fine-scale panel data from Washington, D.C., I exploit variation in the timing of IZ project completions in a stacked event-study design. I find that IZ completions expand realized access for low-income households, with little evidence of displacement among low-income incumbents. Nearby market-rate rents decline, and local business activity increases following development. To evaluate citywide effects, I develop and estimate a spatial equilibrium model with household sorting, endogenous amenities, and developer supply decisions. The model quantifies how IZ affects access to high-opportunity neighborhoods, housing supply, affordability, and residential sorting, and identifies the affordability requirements under which IZ expands access without substantially reducing housing supply and weakening integration.

Abstract: We study how quantity-based labor regulations affect technology adoption using California’s nurse staffing mandate. Combining nationwide hospital data with a synthetic difference-in-differences design, we show that the mandate reduced adoption of Clinical Decision Support systems by up to 6.4 percentage points among hospitals with low baseline staffing conditions or tight financial constraints. Conversely, adoption of nurse staffing software increased by up to 9 percentage points among well-staffed, financially flexible hospitals. These patterns reflect the crowding out of quality-enhancing technologies and increased demand for compliance tools. Overall, staffing mandates shift the technology investment composition, with implications for mortality and clinical performance.

Abstract: This paper provides the first causal evidence on conditional early release by studying Pennsylvania’s Recidivism Risk Reduction Incentive (RRRI). Using quasi-random assignment to sentencing judges as an instrument for RRRI eligibility, we estimate effects on in-prison behavior and post-release outcomes. RRRI reduces time served by 270 days, but has little effect on program completion or misconduct. Post-release, RRRI increases parole violations without increasing new convictions. The increase is concentrated in drug-related and low-level infractions, consistent with greater monitoring under parole supervision. A cost-benefit calculation suggests substantial net welfare gains, highlighting conditional early release as a scalable but supervision-sensitive policy tool.

Abstract: Improving safety is one of the most urgent tasks in South Korea due to a growing fear of accidents and an increasing number of accidents nationwide. The goal of this paper is, based on the law and economics view that accidents are predominantly determined by precaution effort, to identify the main determinants of accident fatalities, especially focusing on income inequality. As an intermediate mechanism between income inequality and safety, we attempt to strengthen the theoretical relationship by introducing safety investment (i.e., a proxy of precaution effort). We then test the hypothesis by analyzing a panel of South Korean administrative regions between 2000 and 2018. We find that major determinants of the accident fatalities identified in the literature have high explanatory powers in the empirical analysis that utilized Korean data. The findings were consistent when we estimated the equation with a different dependent variable (i.e., the transport accident fatalities that are a subset of the total accident fatalities). The estimates of the transport-related variables became more significant, reinforcing its empirical suitability. Finally, it is found that income inequality is positively correlated with the accident fatalities in all model specifications. The estimates indicate that an increase in the Gini coefficient by 0.05 could account for as much as 3% of the accident fatalities that actually took place in 2018. Our estimation results suggest that various policies are needed to handle decreased demand in safety investment caused by income inequality.

Abstract: Available evidence suggests holding companies employ numerous expedients and produce side effects, including expanding their control with a small percentage of shareholdings, defrauding their interests, and increasing the concentration of economic power. This article investigates regulatory reforms in the holding companies. We present several improvement measures through statistical evidence and case studies of South Korea’s corporation groups. We propose strengthening regulations on having subsidiary companies (and grandchild companies), adding requirements regarding line-of-business when owning grandchild or great-grandchild companies, and prohibiting two subsidiaries from having the same grandchild company. Besides, other improvements involve strengthening disclosure of holding companies and intensifying prerequisites for determining holding companies.