报告人:孙强
报告地点:人民大街校区数学与统计学院415会议室
报告时间:2026年06月15日星期一10:00-11:00
邀请人:王晓飞
报告摘要:
Real-world data often conceal meaningful signals beneath both random and structured noise. Structured noise arises in many settings, from batch effects in biomedical studies to background variation in image classification. Interestingly, algorithms that encourage diversity or uniformity in their learned representations tend to generalize better across contexts. To investigate this phenomenon, we study linear representation learning with two views, comparing classical and contrastive methods, both with and without a uniformity constraint. We find that classical non-contrastive algorithms fail in the presence of structured noise. Contrastive learning with only an alignment loss performs well when background variation is mild but breaks down under strong structured noise. In contrast, contrastive learning that enforces a uniformity constraint remains robust regardless of the magnitude of the background noise. Building on these insights, we further explore strategies for designing algorithms that maintain robustness under broader conditions, including random noise and nonstationary environments, by appropriately augmenting the data and problem conditions.
主讲人简介:
Qiang Sun is an associate Professor in the Departments of Computer and Mathematical Sciences, Statistical Sciences, and Computer Science at the University of Toronto (UofT), and a visiting professor at the Mohamed bin Zayed University of Artificial Intelligence (MBZUAI), where he leads the NeXAIS Lab. His research lies at the intersection of statistics and AI, with a focus on trustworthy AI, efficient generative AI (GenAI), and the foundations of AGI. His work is often inspired by real-world challenges in technology, finance, and science. Prior to joining UofT, he was an Associate Research Scholar at Princeton University. He received his Ph.D. in Statistics from the University of North Carolina at Chapel Hill (UNC-CH) and his B.S. in SCGY from the University of Science and Technology of China (USTC).