Yannis Montreuil

Research Interests

I study the mathematical foundations of routing and decision-making problems under uncertainty, with applications to multi-agent and hybrid systems. A central focus of my work is Learning-to-Defer — a framework in which predictive models learn not only to make decisions, but also to strategically abstain and defer to external experts when confidence is low.

My research focuses on formally characterizing when deferral is beneficial and how models can learn to defer in a provably optimal way, drawing on tools from statistical learning theory and decision theory.

TLDR: In essence, I teach models not only what to decide, but when to ask for help

Publications

• Yannis Montreuil, Towards Robust Human–AI Decision-Making via Learning-to-Defer (2025). AAAI-26 Doctoral Consortium.
• Yannis Montreuil, Duy Dang Hoang, Maxime Meyer, Axel Carlier, Lai Xing Ng, & Wei Tsang Ooi (2025). Online Learning-to-Defer with Varying Experts.
• Yannis Montreuil, Letian Yu, Axel Carlier, Lai Xing Ng, & Wei Tsang Ooi (2025). Adversarial Robustness in One-Stage Learning-to-Defer.
• Yannis Montreuil, Axel Carlier, Lai Xing Ng, & Wei Tsang Ooi (2025). Why Ask One When You Can Ask k? Learning-to-Defer to the Top-k Experts. arXiv preprint arXiv:2504.12988.
• Yannis Montreuil, Axel Carlier, Lai Xing Ng, & Wei Tsang Ooi (2025). Adversarial Robustness in Two-Stage Learning-to-Defer: Algorithms and Guarantees. arXiv preprint arXiv:2502.01027. Accepted to ICML 2025
• Yannis Montreuil, Yeo Shu Heng, Axel Carlier, Lai Xing Ng, & Wei Tsang Ooi (2025). A Two-Stage Learning-to-Defer Approach for Multi-Task Learning. arXiv preprint arXiv:2410.15729. Accepted to ICML 2025
• Yannis Montreuil, Axel Carlier, Lai Xing Ng, & Wei Tsang Ooi (2024). Optimal Query Allocation in Extractive QA with LLMs. arXiv preprint arXiv:2410.15761.

Talks

• Yannis Montreuil (Oct 2025): Who Should Decide? Routing Decisions Between Agents with Guarantees, NUS AI Seminar.
• Yannis Montreuil (Oct 2023): Human-AI in Decision-Making, Ethics of autonomy in Smart Cities, DesCartes Symposium.
• Yannis Montreuil (July 2023): Learning to Defer with Support Vector Machine, From Human-Human to Human-AI Collaboration, Association for the Advancement of Artificial Intelligence.

Awards

• Recipient of the NUS School of Computing Research Incentive Award, granted to students that have demonstrated good academic standing and research progress (2023).
• Recipient of the Outstanding Academic Achievement Award from Arts et Métiers, granted to top students (2021).

Reviewer

• AISTATS 2026, ICLR 2026

Teaching

• CS5242 Neural Networks and Deep Learning
• CP2107 Independent Introduction to CS Research

Students

• AY24/25: Yeo Shu Heng, Dang Hoang Duy, Letian Yu
• AY23/24: Seah Min-Rei, Yeo Shu Heng, Dang Hoang Duy