CCDS Dean Wins Distinguished Paper Award at POPL 2025

NTU Vice President (AI & Digital Economy) and CCDS Dean Professor Luke Ong together with collaborators Prof Andrzej Murawski (University of Oxford) and Fabian Zaiser (CCDS alumnus), has received the Distinguished Paper Award at the 52nd ACM SIGPLAN Symposium on Principles of Programming Languages (POPL 2025).

The winning paper, titled "Guaranteed Bounds on Posterior Distributions of Discrete Probabilistic Programs with Loops," introduces two novel and fully automated approaches to determine upper and lower probability bounds in probabilistic programs that include loops. These approaches, termed Residual Mass Semantics and Geometric Bound Semantics, provide foundational tools to analyse the behaviour of such programs — a longstanding challenge in formal verification.

The team’s work directly supports reliability in safety-critical systems, from AI-driven robotics and finance to autonomous healthcare diagnostics, where understanding and constraining probabilistic behaviours is essential.

As part of their research, the team also developed Diabolo, a verification tool that applies their techniques to real-world examples. Diabolo enables the static analysis of probabilistic programs in a robust and interpretable way, offering researchers and engineers a valuable resource for verifying algorithmic behaviour under uncertainty.

The recognition at POPL underscores CCDS’s strength in foundational computer science and formal methods, areas that underpin the safe and rigorous application of AI.