Celebrating the 45th Anniversary of the University of Macau:
Indirect Versus Direct Effects of Port Congestion Through Global Supply Chains
Prof. Xiaole WU
Professor of Management Science
School of Management
Fudan University
Date: 21 May 2026 (Thursday)
Time: 10:30-12:00
Venue: E22-G008
Host: Prof. Zhaotong LIAN, Professor in Business Intelligence and Analytics
Abstract
Using high-frequency shipping data, we construct a novel port-level congestion measure and examine how congestion propagates through supply chains to affect downstream firm performance. Specifically, while a focal firm’s own port congestion has no significant impact on its sales, its domestic suppliers’ port congestion leads to substantial sales declines for the focal firm, revealing contrasting effects of direct shocks and indirect shocks. Counterintuitively, indirect shocks, rather than direct ones, have pronounced effects, revealing diverse risk management attitudes towards different sources of risks. These results hold when instrumenting congestion with local wind speed. Further mechanism analyses show that supplier congestion reduces focal firms’ inventories—particularly raw materials—though higher pre-shock inventory buffers this effect, and that firms relying on more specialized inputs are more vulnerable. Heterogeneity analyses indicate that the ripple effects from domestic suppliers are stronger when suppliers are distributors or operate in time-sensitive industries, and that smaller firms experience larger impacts. These results imply that delay of a firm’s international supplier’s delivery due to port congestion is non-consequential, but a firm’s domestic suppliers, which seem more reliable than international suppliers, can impose a severe impact on the focal firm once their supply is affected. This leads to a strong message: firms should also watch closely their domestic suppliers, especially distributors or those operating in time-sensitive industries.
Speaker
Xiaole (Sherri) Wu is a Professor of Operations & Supply Chain Management at School of Management, Fudan University, and the director of Fudan Center for Global Supply Chains. She holds a Ph.D. in Operations & Supply Chain Management from Olin Business School, Washington University in St. Louis (2011) and a B.S. in Industrial Engineering with Honor from Tsinghua University (2006). Her research focuses on supply chain management, risk management and sustainable operations. She has published in top-tier journals including Management Science and Manufacturing & Service Operations Management, and is the principal investigator of several major national research grants—such as the NSFC Major Project on supply chain resilience (2023–2027) and the NSFC Outstanding Young Scholar Fund (2021–2025). She has won awards such as the 2024 Huawei Supply Chain Collaborative Innovation Award and 2021 Shanghai Woman Pacesetter. She holds editorial roles including Associate Editor of Management Science (2025–present), Senior Editor of Production and Operations Management (2018–present), and Department Editor of China’s flagship Journal of Management Sciences in China (2022–present). She also serves on the 9th Expert Advisory Committee of the NSFC Management Sciences Department (2023–2026).
All are welcome!
