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Welcome!

I am a Ph.D. candidate in Economics at Yale University, specializing in Urban Economics, International Trade, and Industrial Organization.
I am on the 2022-2023 job market.
You can find my CV here.

 

Measuring Welfare Gains from Online Stores: Theory and Evidence from the Supreme Court's Wayfair Decision

with Yang Su, Job Market Paper

We study how the rise of e-commerce has reshaped consumer welfare and its distributional implications in the presence of retail oligopoly. Based on new data on shopping receipts, we document consumer heterogeneity in online retailing markets: households living in rural areas and with higher incomes are more likely to shop online. To quantify the welfare effects, we leverage an exogenous tax shock by the Supreme Court's Wayfair Decision to learn about online store substitutability and firm pricing responses. We then develop and estimate a structural demand and supply model focussing on the pet food retail market. The model allows us to decompose the consumer online welfare gains into gains from varieties (9%) and convenience (5%) and gains from pro-competitive effects (3%). We further characterize the distributional effects of the rise of e-commerce and find it has reduced consumption inequality between rural and urban areas but increased consumption inequality between the rich and the poor.

The Economics of Traveling:
A Study of High-Speed Railway Expansion

Travel flows across cities are large, and infrastructure facilitating human mobility over longer distances has recently raised policymakers' attention. However, how human mobility affects regional development and welfare remains underexplored due to limited measurement of travel flows and their mixed purposes. In this paper, I use high-frequency GPS data of mobile maps app users in China to measure people's travel flows across cities and their business/ leisure activities. I find that spatial frictions in the form of travel time significantly shape travel flows, and travelers' business and leisure activities are associated with the industrial composition of the business service and tourism sectors in the cities. To study how infrastructure improvement affects regional development and welfare through human mobility, I examine China's recent expansion of the High-Speed-Railway system (HSR) since HSR only reduces people's travel costs, not goods' trade costs. I develop and estimate a new spatial model with worker and consumer mobility to study how HSR (1) boosts business and leisure travel, (2) reshapes the industrial structure of cities, and (3) brings unequal welfare gains across cities. Ignoring the human mobility aspect of infrastructural improvement could underestimate the welfare gains by 0.3 percent.

Draft coming soon

Ecommerce and the Retail Apocalypse

I study the long-run effect of the rise of e-commerce on retail branch closures. I first develop a tractable framework to study the equilibrium effect of online penetration on retail firms' branching decisions. To gauge the causal effect of rising e-commerce on the retail apocalypse, I use a shift-share design exploiting cross-retailer variations in online exposure stemming from the initial sectoral composition of the retailers and instrumenting local online market share using online penetrations in other geographically separating markets. I found that the rise of e-commerce caused retail branch closures, but the effects are minor.

Draft coming soon