Domestic Trade Shocks from E-Commerce Expansion: Evidence from Amazon’s Distribution Facilities

[earlier version] [slides] July 2025

• This paper studies Amazon's distribution facility expansion as a domestic trade shock, using detailed data on Amazon facilities, products, and sellers. I develop a spatial trade model with endogenous online entry and consumer search. Guided by the model, I find that facility entry raises local online seller activity and sales, consistent with reductions in shipping frictions and increases in interregional trade. Quantitative results show gains in state-level welfare driven by price effects, but widening regional disparities in real income. 

• Subsumes an earlier working paper "E-commerce and Regional Inequality: A Trade Framework and Evidence from Amazon’s Expansion"​​​

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Occupational Skill Mixing Under Technological Change (JMP)

[current version] [slides] May 2025

• I document that the U.S. economy experienced a significant increase in skill mixing from 2005 to 2024, across existing jobs and new vacancies. Employers increasingly demand mixed non-routine skills instead of specialization, particularly for low- to medium-wage occupations. Meanwhile, workers in occupations that mix non-routine skills or those with a broader set of these skills earn a wage premium. To understand these shifts, I build a multi-dimensional directed search model with endogenous occupation design and skill investment. Counterfactual analysis indicates rising skill complementarity and operational costs as key drivers of skill mixing, as well as aggregate wage and employment shifts.

• Subsumes an earlier working paper "Optimal Skill Mixing Under Technological Advancements"