Jiancong Xiao is a tenure-track Assistant Professor in the Department of Computer Science, School of Computing, at the National University of Singapore (NUS). Prior to joining NUS, he was a postdoctoral researcher at the University of Pennsylvania, working with Prof. Qi Long and Prof. Weijie Su. He received his Ph.D. from The Chinese University of Hong Kong, Shenzhen, advised by Prof. Zhi-Quan (Tom) Luo. His research lies at the intersection of learning theory, statistics, and optimisation, with a focus on building theoretical foundations for responsible and trustworthy machine learning models. His recent work studies mathematical and statistical foundations of large language models, including preference alignment, fine-tuning and post-training, calibration, algorithmic bias. Previously, he worked on adversarial robustness, and robust generalisation. His research has been published in leading journals, including JMLR, the Annals of Statistics, and JASA, as well as top machine learning conferences, including COLT, NeurIPS, ICML, and ICLR. More information can be found at https://jiancongxiao.github.io.