Research

Publication:

“Transportation Infrastructure and Trade” with Zheng Han, Japan and the World Economy, Vol. 64, 2022, 101162.

This paper offers a variant of the Ricardian model able to structurally interpret the estimate of country specific variable—transportation infrastructure. Guided by this new theoretical framework, this paper shows that transportation infrastructure enhances international trade more than internal trade. Further quantitative analysis suggests 10% increase in transportation infrastructure induces about 4% increase in real income and more than 95% of the gains concentrate on the infrastructure improving country. This paper also suggests that transportation infrastructure improvement increases real income mostly through internal trade cost reduction. All the above results suggest that better infrastructure leads to sizable gains providing additional empirical support to policies aiming to improve transportation infrastructure.

Working Paper:

“Optimal Containment Policy with Private Protection” (Job market paper) (Under review at Economic Modelling)

In this paper, I develop a macro-SIR model to analyze how private protection changes optimal containment policy. Mask-wearing as a form of private protection reduces infection risk without requiring a proportional reduction in economic activity and, when sufficiently effective, qualitatively reshapes the optimal containment path. Optimal containment can be phase-shifted-remaining relatively flat during the infection upswing and tightening as infections decline. Under the benchmark calibration, mask-wearing reduces infections more strongly and causes a smaller recession than containment when each is considered in isolation. Although mask-wearing is effective in suppressing transmission, containment remains welfare-improving because it mitigates the infection externality generated by infected individuals’ economic activity.

“Lockdown Policy Rules with a Hospital Capacity Constraint” with Taisuke Nakata, Hiroki Sakamoto, and Hiroyuki Uneya (Under review at Journal of the Japanese and International Economies)

We analyze how hospital capacity affects health and economic outcomes during a pandemic using a macro-SIR model featuring a lockdown policy rule. The rule instructs the government to implement a lockdown when the number of ICU patients exceeds a trigger threshold—motivated broadly by a hospital capacity constraint—and to lift the lockdown when it falls below a lifting threshold. When vaccines are not available, we find that the government can reduce both COVID-19 deaths and economic loss by raising the trigger threshold in some situations. When the vaccine rollout is expected to begin in the near future, we find that the government can reduce both COVID-19 deaths and economic loss by lowering the trigger threshold.

“Real-Time Covid-19 Projections in Tokyo: Lessons for Future Pandemics” with Jianing Chu and Taisuke Nakata

We examine the properties of five real-time COVID-19 infection projections in Tokyo. We find that projections tended to be (i) pessimistic, (ii) less accurate during the fifth infection wave, and (iii) optimistic before the peak and pessimistic after the peak. If policymakers and the public were to utilize real-time projections in future pandemics, it would be useful for them to be aware of the properties of these projections.