activity
20202026
collaborators

9 papers

cs.LG2026

Reflections and Fragments: Securing LLMs Against Sequential Mosaic Attacks

Emanuele La Malfa, Saar Cohen, Gabriele La Malfa +4

Self-play red-teaming improves language-model safety by pitting attacker and defender roles against each other in a zero-sum game. However, real adversaries increasingly use mosaic…

cs.GT2026

Online Fair Division under an Oblivious Adversary

Saar Cohen, Nicholas Teh, Michael Wooldridge

We study online fair division, where indivisible goods arrive one at a time and must be allocated immediately and irrevocably among agents. Against an oblivious adversary t…

cs.GT2026

Online House Allocation with Subsidy

Nicholas Teh, Saar Cohen, Karen Frilya Celine +2

House allocation is a fundamental problem in which each agent is assigned exactly one house. While the classical model assumes that all houses are available before the allocation i…

cs.GT2026

Online Fair Division with Budget Constraints

Saar Cohen, Nicholas Teh, Paul W. Goldberg +1

We study an online variant of discrete fair division under generalized assignment budget constraints. Goods arrive one at a time and must be assigned irrevocably to a feasible agen…

cs.AI2026

The Attacker in the Mirror: Breaking Self-Consistency in Safety via Anchored Bipolicy Self-Play

Gabriele La Malfa, Emanuele La Malfa, Saar Cohen +4

Self-play red team is an established approach to improving AI safety in which different instances of the same model play attacker and defender roles in a zero-sum game, i.e., where…

cs.GT2026

Offline Learning of Nash Stable Coalition Structures with Possibly Overlapping Coalitions

Saar Cohen

Coalition formation concerns strategic collaborations of selfish agents that form coalitions based on their preferences. It is often assumed that coalitions are disjoint and prefer…

cs.MA2026

Delayed Assignments in Online Non-Centroid Clustering with Stochastic Arrivals

Saar Cohen

Clustering is a fundamental problem, aiming to partition a set of elements, like agents or data points, into clusters such that elements in the same cluster are closer to each othe…

cs.LG2025

Convexified Message-Passing Graph Neural Networks

Saar Cohen, Noa Agmon, Uri Shaham

Graph Neural Networks (GNNs) are key tools for graph representation learning, demonstrating strong results across diverse prediction tasks. In this paper, we present Convexified Me…

cs.MA2020

Converging to a Desired Orientation in a Flock of Agents

Saar Cohen, Noa Agmon

This work concentrates on different aspects of the \textit{consensus problem}, when applying it to a swarm of flocking agents. We examine the possible influence an external agent,…