Yuhan Wang

Research

Job Market Paper

Shipment Networks and Market Power in U.S. Poultry Procurement

Job Market Paper

How do market power and geography shape the cost of supply-chain shocks in U.S. poultry procurement? Linking Commodity Flow Survey shipment records to Census establishment microdata, I classify unobserved shipment channels with a random forest and estimate random-coefficients nested logit demand with multi-product Bertrand supply. Wholesale buyers are roughly three times as price sensitive as food-service buyers, and shipment distance raises marginal cost while lowering differentiated-product demand. An industry-wide raw-poultry cost shock lowers total surplus by 17.7 percent and localized plant shutdowns by 4.8 percent; a merger of the third- and fourth-largest firms raises average unit values by about 7 percent and converts 59 percent of downstream buyers' losses into deadweight loss.

Paper (PDF)

Working Papers

A Text-Based Measure of Farm Bill Uncertainty and Its Effects on Agricultural Credit

Revision requested at Journal of Agricultural Economics.

This paper develops a Farm Bill Uncertainty Index using a two-stage BERT classifier that isolates newspaper language reflecting legislative delay, disagreement, and procedural impasse. The index tracks negotiation cycles, spiking during conflict and declining after enactment. Merging the index with institution-level data for commercial banks, credit unions, and Farm Credit System institutions shows that higher uncertainty reduces agricultural lending, most clearly for commercial banks: a 0.10 increase in the index is associated with about a 0.37 percent decline in lending. Exposure-weighted and stacked difference-in-differences estimates further show that lending expands more rapidly after uncertainty declines.

Paper (PDF)

Technology, Risk, and Climate Adaptation: Corn Specialization in the U.S. Corn Belt

With Xiaodong Du and Xueying Sun.
Revision requested at American Journal of Agricultural Economics.

This paper studies how technological change facilitates climate adaptation in agricultural land use by examining the evolution of corn specialization in the U.S. Corn Belt. It constructs a county-level Technical Change Index using agro-ecological yield-potential data and combines it with long-run data on land use, weather, and crop insurance outcomes. A structural discrete-choice model shows that technology raises the returns to specialization and reduces exposure to downside weather risk, generating adaptation gains of about $0.85 per acre under greater climate volatility.

Paper (PDF)

Selected Work in Progress