Research
("Previously circulated as "The Valuation of Local Government Spending: Gravity Approach and Aggregate Implications”)
What are the aggregate welfare consequences of fiscal transfers across local governments that finance their spending? Answering this question requires an understanding of how much people value local public spending. I develop a spatial equilibrium framework in which workers' simultaneous migration and commuting choices reveal preferences. I combine this framework with unique data from South Korea and leverage tax reforms as a source of exogenous variation. The estimated mobility responses imply that workers value an additional dollar of per-capita local government spending at 75 cents of their after-tax income. General-equilibrium counterfactuals imply that a fiscal arrangement with lower redistribution would result in aggregate gains. A key aspect of my analysis is that bilateral migration and commuting decisions are jointly made. Ignoring either of these margins biases the estimates of preferences for public goods, and of distance elasticities of migration or commutingm which play a central role in quantitative spatial models.
“Heterogeneous Local Employment Multiplier: Evidence from Relocations of Public Entities in South Korea” (with Changsu Ko and Hwanwoong Lee), January 2023. Draft
In this paper, we exploit a series of the relocation of public-sector entities in South Korea as an exogenous source of variation in public sector employment to estimate local employment multiplier. We find that an introduction of 1 public sector employment increases the private sector employment by 1 unit, almost completely driven by the service sector. In line with the literature, we document that the effect of public employment on private employment is highly localized. In addition to changes in private employment, we also find that the relocation led to a positive net-inflow of residents into the treated neighborhood; this effect is also localized. Lastly, we estimate heterogeneous local employment multiplier and provide evidence that this heterogeneity is shaped by the size of public sector shocks, different types of relocation, and the extent of migratory responses.
Total fertility rates have declined across many developed countries. Many policies have been implemented in an attempt to reserve this trend. This paper presents novel causal evidence on the effects of one such policy—pro-natalist financial incentives offered in South Korea—on fertility, sex, and infant health. I exploit rich spatial and temporal variation in cash transfers provided to families with newborn babies and the universe of birth, death, and migrant registry records. I find that the total fertility rate in 2015 would have been 3% lower without the cash transfers. The selection of working mothers into childbearing decreased gestational age, leading to an overall reduction in birth weight, but no change in early-life mortality. The cash transfers had an unintended consequence of correcting the unnaturally male-skewed sex ratio.
“Optimal Lockdown in a Commuting Network” (with Pablo Fajgelbaum, Amit Khandelwal, Cristiano Mantovani, and Edouard Schaal), American Economic Review: Insights, 2021 Vol 3. Slides / VoxEU / Codes and Replication
We study optimal dynamic lockdowns against Covid-19 within a commuting network. Our framework integrates canonical spatial epidemiology and trade models, and is applied to cities with varying initial viral spread: Seoul, Daegu and NYC-Metro. Spatial lockdowns achieve substantially smaller income losses than uniform lockdowns, and are not easily approximated by simple centrality-based rules. In NYM and Daegu—with large initial shocks—the optimal lockdown restricts inflows to central districts before gradual relaxation, while in Seoul it imposes low temporal but large spatial variation. Actual commuting responses were too weak in central locations in Daegu and NYM, and too strong across Seoul.
Work in Progress
Please refer to my CV
Data
Commuting and migration in Korea (2005; 2010; 2015): this dataset is used in "The Valuation of Local Government Spending: Gravity Approach and Aggregate Implications" and constructed based on the Population Census of Korea 2005, 2010, and 2015. ***permission required for data use***