Charilaos Pipis — accepted AI-conference papers

2026

Wait, Wait, Wait... Why Do Reasoning Models Loop?

Charilaos Pipis, Shivam Garg, Vasilis Kontonis, Vaishnavi Shrivastava, Akshay Krishnamurthy, Dimitris Papailiopoulos

ICML 2026spotlight

Reasoning models (e.g., DeepSeek-R1) generate long chains of thought to solve harder problems, but they often loop, repeating the same text at low temperatures or with greedy decoding. We study why this happens and what role temperature plays. With open reasoning models, we find that looping is comm…

Cited by 0 Source ↗Scholar ↗

2024

Polynomial-Time Computation of Exact $\Phi$-Equilibria in Polyhedral Games

Gabriele Farina, Charilaos Pipis

NeurIPS 2024spotlight

It is a well-known fact that correlated equilibria can be computed in polynomial time in a large class of concisely represented games using the celebrated Ellipsoid Against Hope algorithm \citep{Papadimitriou2008:Computing, Jiang2015:Polynomial}. However, the landscape of efficiently computable equi…

Cited by 7 Source ↗PDF ↗Scholar ↗

2023

Polynomial-Time Linear-Swap Regret Minimization in Imperfect-Information Sequential Games

Gabriele Farina, Charilaos Pipis

NeurIPS 2023poster

No-regret learners seek to minimize the difference between the loss they cumulated through the actions they played, and the loss they would have cumulated in hindsight had they consistently modified their behavior according to some strategy transformation function. The size of the set of transformat…

Cited by 16 Source ↗PDF ↗Scholar ↗