On June 13, 2026, Professor Yang Xuewei from Nanjing University was invited to the School of Mathematical Sciences to deliver an academic talk. In addition to faculty members and master's and doctoral students from the school, the lecture was also attended by Zhang Caibin and Yang Bo from Nanjing University of Finance and Economics, and Yuan Yu from Nanjing University of Information Science and Technology.Professor Yang Xuewei's talk is entitled "Big Data Price Discrimination Against Regular Customers: Information Advantage and Dynamic Price Discrimination." The study introduces bounded rationality into market pricing theory to explain the pricing puzzle in China's stock brokerage service market. It primarily examines whether market competition can constrain financial service pricing when financial service providers identifycustomer types through long-term cooperative relationships. The study establishes a dynamic brokerage competition analysis framework: brokers set trading commissions based on their own assessment of customer sophistication levels ("naive" or "sophisticated"). The commission spread does not arise from strategic random games, but rather from differences in brokers' judgments about customers under information asymmetry. The paper finds that long-term cooperation gives established brokers a unique customer information advantage. Evenwhen a customer is identified as having sophisticated investment capabilities, established brokers do not need to offer extremely low commissions, as competitors can hardly assess the customer's level with the same precision. This exclusive customer information cannot be shared, which firmly retains existing customers and perpetuates differentiated pricing models. In other words, long-term sophisticated customers are partially locked in with theirincumbent broker who knows their reputation — the so-called "price discrimination against regular customers." Bycombining data from China's retail securities brokerage market, the study ultimately validates the model's conclusions: while industry competition has lowered overall average commissions, it has widened the gap betweenhigh and low commissions, further enlarging the fee differential between sophisticated investors and ordinary retail investors. Data calculations show that blindly intensifying industry competition may have counterproductive effects — it will not only exacerbate fee differentiation but also slow down the overall reduction in commission rates.After the report, Professor Yang's research findings sparked lively discussions among the attendees. Several participating teachers, drawing on their own research areas, raised questions one by one about modelspecifications, market empirical results, differentiated pricing mechanisms, and other topics of interest. Both sides engaged in detailed Q&A regarding the paper's specifics, and jointly outlined and envisioned potential research directions for further extension of this topic. At the end of the discussion, Professor Liang Zhibin deliveredconcluding remarks, affirming the innovative value and practical reference significance of this research. He also summarized the core viewpoints of the entire seminar and provided guidance for faculty and students present to conduct future research in related fields of financial pricing and brokerage competition.（By Zhibin Liang）