activity
20232026
most citedReward Model Ensembles Help Mitigate Overoptimization

2 citations · 3 across the 6 of their papers we have counts for

collaborators

7 papers

cs.CL2026

Shieldstral

Antonia Calvi, Avinash Sooriyarachchi, Giada Pistilli +273

We introduce Shieldstral, a 3B-parameter policy-adaptive multimodal safety classifier that matches or outperforms models nearly 7 its size on text safety benchmarks and set…

cs.LG2025

Succeed or Learn Slowly: Sample Efficient Off-Policy Reinforcement Learning for Mobile App Control

Georgios Papoudakis, Thomas Coste, Jianye Hao +2

Reinforcement learning (RL) using foundation models for policy approximations in multi-turn tasks remains challenging. We identify two main limitations related to sparse reward set…

cs.AI2025

AppVLM: A Lightweight Vision Language Model for Online App Control

Georgios Papoudakis, Thomas Coste, Zhihao Wu +3

The utilisation of foundation models as smartphone assistants, termed app agents, is a critical research challenge. These agents aim to execute human instructions on smartphones by…

cs.AI2024

Lightweight Neural App Control

Filippos Christianos, Georgios Papoudakis, Thomas Coste +3

This paper introduces a novel mobile phone control architecture, Lightweight Multi-modal App Control (LiMAC), for efficient interactions and control across various Android apps. Li…

cs.LG2024★ 1 cited

Bayesian Reward Models for LLM Alignment

Adam X. Yang, Maxime Robeyns, Thomas Coste +4

To ensure that large language model (LLM) responses are helpful and non-toxic, a reward model trained on human preference data is usually used. LLM responses with high rewards are…

cs.AI2023

Pangu-Agent: A Fine-Tunable Generalist Agent with Structured Reasoning

Filippos Christianos, Georgios Papoudakis, Matthieu Zimmer +13

A key method for creating Artificial Intelligence (AI) agents is Reinforcement Learning (RL). However, constructing a standalone RL policy that maps perception to action directly e…

cs.LG2023★ 2 cited

Reward Model Ensembles Help Mitigate Overoptimization

Thomas Coste, Usman Anwar, Robert Kirk +1

Reinforcement learning from human feedback (RLHF) is a standard approach for fine-tuning large language models to follow instructions. As part of this process, learned reward model…