I study various topics in trade and urban economics. My research explores the redistributive effects of economic policies and shocks across space and time, and therefore, my research interests extend to the intersection of international trade, economic geography, and labour economics.

Publications

The Economic Dynamics of City Structure: Evidence from Hiroshima's Recovery

(with Atsushi Yamagishi), Accepted at the Journal of Political Economy

Can a city recover its internal structure after being devastated? Studying Hiroshima after the atomic bombing, we show that its city centre re‑emerged surprisingly quickly. A dynamic urban model explains this recovery through strong agglomeration forces and forward‑looking choices by households—while also showing that recovery was not guaranteed and depended crucially on expectations.

[Manuscript] [Online Appendix] [Presentation Slides] [Replication Package]
Press: [VoxEU article] [VoxDev article] [CEP CentrePiece] [Toyo Keizai Column] [podcast-Densely speaking]

Working Papers

The Geography of Structural Transformation: Effects on Inequality and Mobility

Why do some places keep producing opportunity while others fall behind? This paper shows that when industries grow and decline at different speeds across regions, they leave long‑lasting imprints on local jobs and incomes. I develop a model in which past industrial exposure shapes today’s career paths, helping explain why inequality and intergenerational mobility differ so sharply across cities.

CEP Discussion Paper #1893
[Manuscript] [Online Appendix] [Web-based Supplementary Material (numerical results)]
Press: [USAPP blog post]

Trade and Intergenerational Income Mobility: Theory and Evidence from the U.S.

(with Italo Colantone and Gianmarco I.P. Ottaviano)

How does globalisation affect the economic fortunes of the next generation? I show that regions hit harder by import competition experienced lower upward mobility among children, not just short‑run job losses. Trade shocks reduce wage growth and limit opportunities to move or switch careers, leaving lasting effects on where children end up relative to their parents.

[Manuscript] [Online Appendix]

Universities and the Rise of Services

(with Liu Change)

Why do some regions transition into high‑skill services faster than others? This paper shows that universities play a central role, not only by educating workers but by fostering new tasks and industries. Regions with universities see faster growth in skilled services and higher wages because universities act as hubs for talent and innovation, reshaping local economies.

Global Spillovers of Environmental Policy: Evidence from Japan’s Waste Exports

(with Yusuke Kuroishi, Kentaro Nakajima, Yasuyuki Sawada, Yutaro Takayasu and Mari Tanaka)

Environmental policies often stop at national borders — but their effects do not. When China restricted waste imports, Japanese exporters redirected shipments to other countries and altered what they produced. These adjustments were incomplete, leading to lasting export losses and environmental spillovers. The results show how unilateral environmental regulation can reshape global trade in unintended ways.

[Manuscript]

How Useful are Quantitative Urban Models for Cities in Developing Countries?

(with Daniel Sturm and Anthony Venables)

Many fast‑growing cities lack the data needed for estimating quantitative urban models. This paper shows how mobile phone data and satellite imagery can fill that gap. Using Dhaka as a case study, we demonstrate that modern urban models can be estimated even in data‑scarce settings and used to evaluate infrastructure and densification policies in developing‑country cities.

[Manuscript]

Exploring the Urban Model: Employment, Housing, and Infrastructure

(with Daniel Sturm and Anthony Venables)

We provide a guided tour of modern urban economic models. We show how jobs, housing, and infrastructure interact to shape city size and structure, and how different policies affect urban form. The analysis helps clarify when cities become centralized or decentralized and offers a flexible framework for thinking about real‑world urban policy problems.

[World Bank WP #9910, January 2022]

Highways, High-Speed Railways, and Urban Growth: Evidence from Japan 1970 - 2015

(with Tomoya Mori)

Studying highways and high‑speed rail in Japan, we show that better transport concentrates growth in some cities while spreading activity within cities. Distinguishing between different types of accessibility gains helps explain why some places grow, others stagnate, and cities themselves become more decentralized.

[Manuscript]

Selected Work in Progress

• “Firms and developers in the dynamics of city structure,“ with Tony Venables

• “Property Taxation in an Ageing Economy,” with Atsushi Yamagishi and Jiro Yoshida

• “Skills in Space,“ with Alessandro Sforza and Tommaso Sonno

• “Empty Homes and House Prices: Evidence from London,” with Daniel Sturm

Selected Comments and Discussions:

• “Sorting to Expensive Cities“ by Cecile Gaubert and Frederic Robert-Nicoud, 2023 CEPR CURE, Torino [slides]

• “Identifying Agglomeration Shadows: Long-run Evidence from Ancient Ports“ by Richard Hornbeck, Guy Michaels and Ferdinand Rauch, 2023 UEA EU meeting, Milano [slides]

• “Market size, trade and productivity reconsidered: Poverty traps and the home market“ by Marcus Berliant and Takatoshi Tabuchi, 2023 UEA NA meeting, Toronto [slides]

• “The Dual Local Markets: Family, Jobs, and the Spatial Distribution of Skills“ by Jingting Fan and Ben Zou, 2024 ABFER meeting, Singapore [slides]

• “Are Big Cities Important for Economic Growth?” by Matthew Turner and David Weil, 2025 UEA NA meeting