Working papers

FDI and Domestic Technology Upgrading: Evidence from Vietnam’s WTO Accession (JMP, draft available upon request) 

Abstract: This paper studies how proximity to foreign-owned plants affects domestic firm productivity---a question of particular importance in developing economies, where FDI is spatially concentrated and internal trade costs limit access to foreign demand. Using geocoded commune-level data from Vietnam, I construct localized MNE exposure and estimate causal effects using difference-in-differences around the 2007 WTO accession. Greater exposure raises productivity by 9.8 percent, with gains and technology upgrading concentrated among middle-productivity firms. I develop a heterogeneous-firm model with fixed costs of supplying MNEs and adopting technology, where local sourcing generates distance-discounted demand. Calibrated to the MNE share of supplier revenue and observed firm-to-FDI distances, the model implies that a 10 percent increase in MNE demand raises aggregate productivity by 0.4 percent. Extending effective reach from 16.5km to 100km raises the gain to 10.9 percent, showing that spatial frictions can substantially limit FDI transmission to domestic firms.

Gains at Risk: Trade Diversion and Policy Risk in the U.S.–China Trade War (draft available upon request)

Abstract: This paper examines the third-country effects of the  U.S.--China trade war on Vietnam. Using firm-level data  linked to product-level exposure, I document that a  one-standard-deviation increase in tariff exposure is associated with approximately 3.8 % higher revenue, alongside active within-firm reallocation of product scope away from tariff-exposed goods. Downstream demand propagation through input--output linkages emerges as the dominant transmission channel. 

I develop a multi-country multi-sector quantitative trade model incorporating a trade policy-risk capturing prospective U.S. tariff escalation targeting Vietnam. While Vietnam emerges as a substantial major beneficiary under a frictionless benchmark, a bilateral tariff escalation of just 3.9% suffices to attenuate these gains by approximately 24.5%. Trade diversion gains are real but fragile.

Uneven Gains from FDI: Firm-Level Evidence from Vietnam, with Yeongwoong Do  (Article Link)

Abstract: This paper examines whether the productivity-enhancing effects of FDI are broadly diffused in the host economy or instead reinforce polarization. While prior research has largely documented positive effects of FDI using macro-level data, we employ firm- and project-level evidence from Vietnam to show that these gains are concentrated among top-tier firms. Average productivity rises, but the distributional effects are uneven: leading firms benefit while lagging firms fall further behind, widening the productivity gap. These findings highlight the heterogeneous impact of FDI and suggest that macro-level analyses may obscure important distributional dynamics.

Agglomeration Effects of Anchor Firms: Evidence from Samsung’s Investment in Vietnam (Article Link)

Abstract: This paper examines how Samsung’s major investments reshaped Vietnam’s industrial landscape and affected the productivity of incumbent manufacturing firms. Samsung established two large plants—Yen Phong (Bac Ninh, 2008) and Pho Yen (Thai Nguyen, 2013)—each worth 7–9 billion USD, transforming these areas into national investment hubs. Using firm-level panel data (2004–2018) and the Synthetic Control Method, the study quantifies Total Factor Productivity (TFP) spillovers to local firms. The donor pool includes comparable counties across Samsung’s host provinces and a middle province matched on geographic and socioeconomic traits. Results reveal contrasting spillovers: Samsung’s Pho Yen plant boosted incumbent firms’ productivity, while the Yen Phong plant had adverse effects—likely due to weaker industrial linkages among local firms.