I'm Stephan, a Postdoctoral Research Associate at Princeton University working with Prof. Arvind Narayanan and Prof. Matthew Salganik at the Center for Information Technology Policy (CITP). Previously, I was a PhD student in Computer Science at the University of Toronto and the Vector Institute working with Prof. Nicolas Papernot.
I work on advancing reliable and trustworthy machine learning. Most notably, I work on uncertainty quantification, selective prediction, and out-of-distribution generalization/robustness. In my past research I have worked on out-of-distribution and selective classification methods, reliability of time series representations, time series anomaly detection, distribution shift detection/characterization, robustness in federated learning, examining the intersection of uncertainty quantification and differential privacy, providing tighter bounds on selective classification performance, designing suitability filters to detect malignant distribution shifts, introducing a confidence tuning method for improved cascading/deferral from small to big models, and studying adversarial use of uncertainty.
Over the past years, I have interned a few times at Amazon / AWS AI Labs as well as Google. I was also research visitor at MIT, CMU, and the University of Cambridge.
News
- May 2026 New preprints: Open-World Evaluations for Measuring Frontier AI Capabilities and Log Analysis is Necessary for Credible Evaluation of AI Agents are out!
- May 2026 Towards a Science of AI Agent Reliability has been accepted to ICML 2026!
- Apr 2026 Gave invited talks at the UMN CSE Data Science Initiative ML Seminar and the UK AI Security Institute.
- Feb 2026 New preprint: Towards a Science of AI Agent Reliability is now available on arXiv!
- Jan 2026 Cascadia has been accepted to ICLR 2026!
- Sep 2025 What Does It Take to Build a Performant Selective Classifier? and Gatekeeper have been accepted to NeurIPS 2025!
- Aug 2025 I have successfully defended my PhD thesis!
- May 2025 Confidential Guardian and Suitability Filter have been accepted to ICML 2025!