CS Colloquium Speaker

Speaker: Shiori Sagawa, Stanford University

Date: Tuesday, March 26

Time: 12:30pm EST

Location: CS 105

Host: Ellen Zhong

Event page: https://www.cs.princeton.edu/events/26601

Title: Distributionally Robust Machine Learning

Abstract: Machine learning models are widely deployed today, but they can fail due to distribution shifts: mismatches in the data distribution between training and deployment. Models can fail on certain subpopulations (e.g., language models can fail on non-English languages) and on new domains unseen during training (e.g., medical models can fail on new hospitals). In this talk, I will discuss my work on algorithms for improving robustness to distribution shifts. First, to mitigate subpopulation shifts, I develop methods that leverage distributionally robust optimization (DRO). My methods overcome the computational and statistical obstacles of applying DRO on modern neural networks and on real-world shifts. Second, to tackle domain shifts, I build WILDS, a benchmark of real-world shifts, and show that existing methods fail on WILDS even though they perform well on synthetic shifts from prior benchmarks. I then develop a state-of-the-art method that successfully mitigates real-world domain shifts; my method proposes an alternative to domain invariance—a key principle behind the prior methods—to reflect the structure of real-world shifts. Altogether, my algorithms improve robustness to a wide range of distribution shifts in the wild, from subpopulation shifts in language modeling to domain shifts in wildlife monitoring and histopathology.

Bio: Shiori Sagawa is a final-year PhD Candidate in Computer Science at Stanford University, advised by Percy Liang. Her research focuses on algorithms for reliable machine learning. She was awarded the Stanford Graduate Fellowship and an Apple Scholars in AI/ML PhD Fellowship. Prior to her PhD, she received her B.A. in Computer Science and Molecular and Cell Biology from UC Berkeley, and she worked at D. E. Shaw Research.