School of Mathematical Sciences Academic Report [2025] No. 038  

(High-Level University Construction Series Report No. 1060)  

Lecture Title: Trading Behavior of Large and Small Investors in the Presence of Large Investor Premium

Speaker: Xu Yuhong (Professor, Soochow University)  

Date & Time: 10:30–11:30 AM, May 17, 2025  

Venue: Room 514, Huixing Building  

Abstract: We develop a theoretical model to study investors' trading behavior in the presence of large investors' influence on a firm's equity. We show that, for a good stock, large investors tend to invest more heavily than smart small investors, even though they predict the same equity returns. However, the smart small investors obtain more welfare and thus perform as free riders in this economy. Moreover, the analyses are extended to firms with more than one influential large investor. We find that: (i) the large shareholders collude in trading, and each tends to invest more aggressively as other large shareholders do, and (ii) firms with sole ownership can outperform those with dispersed ownership, if the impact coefficient of the former case exceeds or coincides with the aggregated impact coefficients of the latter.

Biography: Xu Yuhong is a Full Professor, Ph.D. Supervisor, and Zhongying Young Scholar. She studied under Prof. Shige Peng (Shi-Go Peng). She has held postdoctoral positions at the University of Western Brittany (France) and research fellowships at the National University of Singapore, as well as visiting appointments at the University of Hong Kong and Hong Kong Polytechnic University. Her long-term research focuses on mathematical finance and financial artificial intelligence, with findings published in top international journals such as Mathematical Finance (top journal in financial mathematics) and Management Science (top general management science journal). She currently serves as an executive council member of the Financial Engineering and Risk Management Society of China Operations Research Society, a council member of the Quantitative Finance and Insurance Society of China Optimization, Overall Planning, and Economic Mathematics Society, a council member of the Financial Technology and Big Data Society of the National Industrial Statistics Research Association, and a youth committee member of the Financial Engineering Society of China Association for Industrial and Applied Mathematics. She is also a founder of the Annual Conference on Financial Mathematics and Data Processing. She has led three National Natural Science Foundation projects, two Jiangsu Provincial Natural Science Foundation projects, and one Shanghai Open Project. Her students have won more than 20 awards in fintech-related competitions, with two master’s graduates receiving Jiangsu Provincial Excellent Thesis awards and three receiving Soochow University Excellent Thesis awards.  

All faculty and students are welcome to attend!

Invited by: Li Jingchao

School of Mathematical Sciences  

May 14, 2025