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.

Causal Analysis of Policy Effects on Fertility” (with Rannveig Hart, Janna Bergsvik, and Agnes Fauske), in the Handbook of Labor, Human Resources and Population Economics, edited by Klaus F. Zimmermann, 2024. Earlier Working Paper 

This chapter reviews the literature on the causal effects of policies on fertility. It focuses on evidence from experiments and quasi-experiments in low fertility contexts, including studies from Europe, Northern America, Oceania, and Asia. Making no a priori restrictions on policy type, the review encompasses evaluations of parental leave, childcare, health insurance, and financial incentives such as child transfers. Childcare expansions increase completed fertility. Financial incentives had positive effects on fertility across contexts, both in the short and long run. Expansions of parental leave rights in Central Europe and the introduction of parental leave in the U.S. also had positive effects. The distributional effects of these policies are very different, with parental leave compensation benefiting high-earning couples,  while expansions of childcare programs had potential to reduce social inequalities. Publicly funded contraception and assisted reproduction can reduce fertility in young adulthood and increase fertility for women over the age of 35. 

“Baby Bonus, Fertility, and Missing Women”, August 2023. Draft / Slides / VoxChina (Revise & Resubmit at Journal of Human Resources)

I present novel causal evidence on the effects of pro-natalist cash transfers in South Korea on fertility, the sex ratio at birth, and infant health. I exploit rich spatial and temporal variation in pro-natalist cash transfers and the universe of birth, death, and migrant registry records. The total fertility rate in 2015 would have been 4.7% lower without the cash transfers. Surprisingly, the cash transfers had the unintended consequence of correcting the unnaturally male-skewed sex ratio and lowering gestational age and birth weight. Negative selection into childbearing may explain these effects. 

"Migration, Commuting, and the Spatial Distribution of Public Spending", May 2023. New Draft Available Soon. Old Version here

("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 commuting, which play a central role in quantitative spatial models. 

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. 

Selected Work in Progress

"Talent, College Enrollment, and Spatial Distribution of Economic Activity" with Zhouwei Haung, Devaki Ghose, and Han Xia.

"Heterogeneous Health Effects of Air Pollution: Evidence from Universal Medical Insurance Program in South Korea" with Seonmin Heo, Koichiro Ito, Kanghyock Koh, Rao Kotamarthi, and Eric Zuo. 

"Fiscal Multipliers, Geography, and Consumption Network" with Simon Fuchs, Rocio Madera, and Hoyoung Yoo.

Please refer to my CV for more. 


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***