activity
20182026
most citedLexicographic Multi-Objective Reinforcement Learning

18 citations · 76 across the 19 of their papers we have counts for

collaborators

21 papers

cs.CY2026

Characterizing Agentic Flooding of Government Services

Chris Schmitz, Lewis Hammond, Alan Chan

AI agents are making it easier for the public to interact with government, such as by helping them apply for benefits, understand complex policies, and make their opinions heard. A…

cs.CY2026

Habermolt: Delegating Deliberation to AI Representatives

Joseph Low, Oscar Duys, Claude Formanek +2

Deliberative democracy arguably leads to better collective decisions, but is fundamentally constrained by human attention and bandwidth. While recent AI-mediated deliberations scal…

cs.AI2026

Causal Foundations of Collective Agency

Frederik Hytting Jørgensen, Sebastian Weichwald, Lewis Hammond

A key challenge for the safety of advanced AI systems is the possibility that multiple simpler agents might inadvertently form a collective agent with capabilities and goals distin…

cs.MA2025★ 10 cited

Multi-Agent Risks from Advanced AI

Lewis Hammond, Alan Chan, Jesse Clifton +41

The rapid development of advanced AI agents and the imminent deployment of many instances of these agents will give rise to multi-agent systems of unprecedented complexity. These s…

cs.AI2024

Neural Interactive Proofs

Lewis Hammond, Sam Adam-Day

We consider the problem of how a trusted, but computationally bounded agent (a 'verifier') can learn to interact with one or more powerful but untrusted agents ('provers') in order…

cs.GT2024

Game Theory with Simulation in the Presence of Unpredictable Randomisation

Vojtech Kovarik, Nathaniel Sauerberg, Lewis Hammond +1

AI agents will be predictable in certain ways that traditional agents are not. Where and how can we leverage this predictability in order to improve social welfare? We study this q…

cs.CY2024★ 7 cited

Open Problems in Technical AI Governance

Anka Reuel, Ben Bucknall, Stephen Casper +30

AI progress is creating a growing range of risks and opportunities, but it is often unclear how they should be navigated. In many cases, the barriers and uncertainties faced are at…

cs.AI2024

IDs for AI Systems

Alan Chan, Noam Kolt, Peter Wills +7

AI systems are increasingly pervasive, yet information needed to decide whether and how to engage with them may not exist or be accessible. A user may not be able to verify whether…

cs.LG2024★ 16 cited

Foundational Challenges in Assuring Alignment and Safety of Large Language Models

Usman Anwar, Abulhair Saparov, Javier Rando +39

This work identifies 18 foundational challenges in assuring the alignment and safety of large language models (LLMs). These challenges are organized into three different categories…

cs.GT2024

Cooperation and Control in Delegation Games

Oliver Sourbut, Lewis Hammond, Harriet Wood

Many settings of interest involving humans and machines -- from virtual personal assistants to autonomous vehicles -- can naturally be modelled as principals (humans) delegating to…

cs.AI2024★ 1 cited

Secret Collusion among AI Agents: Multi-Agent Deception via Steganography

Sumeet Ramesh Motwani, Mikhail Baranchuk, Martin Strohmeier +4

Recent capability increases in large language models (LLMs) open up applications in which groups of communicating generative AI agents solve joint tasks. This poses privacy and sec…

cs.CY2024★ 1 cited

Visibility into AI Agents

Alan Chan, Carson Ezell, Max Kaufmann +9

Increased delegation of commercial, scientific, governmental, and personal activities to AI agents -- systems capable of pursuing complex goals with limited supervision -- may exac…

cs.MA2023★ 1 cited

Welfare Diplomacy: Benchmarking Language Model Cooperation

Gabriel Mukobi, Hannah Erlebach, Niklas Lauffer +3

The growing capabilities and increasingly widespread deployment of AI systems necessitate robust benchmarks for measuring their cooperative capabilities. Unfortunately, most multi-…

cs.GT2023

On Imperfect Recall in Multi-Agent Influence Diagrams

James Fox, Matt MacDermott, Lewis Hammond +3

Multi-agent influence diagrams (MAIDs) are a popular game-theoretic model based on Bayesian networks. In some settings, MAIDs offer significant advantages over extensive-form game…

cs.AI2023★ 12 cited

Reasoning about Causality in Games

Lewis Hammond, James Fox, Tom Everitt +3

Causal reasoning and game-theoretic reasoning are fundamental topics in artificial intelligence, among many other disciplines: this paper is concerned with their intersection. Desp…

cs.LG2022★ 18 cited

Lexicographic Multi-Objective Reinforcement Learning

Joar Skalse, Lewis Hammond, Charlie Griffin +1

In this work we introduce reinforcement learning techniques for solving lexicographic multi-objective problems. These are problems that involve multiple reward signals, and where t…

cs.LG2022

Bounded Robustness in Reinforcement Learning via Lexicographic Objectives

Daniel Jarne Ornia, Licio Romao, Lewis Hammond +2

Policy robustness in Reinforcement Learning may not be desirable at any cost: the alterations caused by robustness requirements from otherwise optimal policies should be explainabl…

cs.MA2021

Rational Verification for Probabilistic Systems

Julian Gutierrez, Lewis Hammond, Anthony W. Lin +2

Rational verification is the problem of determining which temporal logic properties will hold in a multi-agent system, under the assumption that agents in the system act rationally…

cs.MA2021★ 6 cited

Equilibrium Refinements for Multi-Agent Influence Diagrams: Theory and Practice

Lewis Hammond, James Fox, Tom Everitt +2

Multi-agent influence diagrams (MAIDs) are a popular form of graphical model that, for certain classes of games, have been shown to offer key complexity and explainability advantag…

cs.AI2021

Multi-Agent Reinforcement Learning with Temporal Logic Specifications

Lewis Hammond, Alessandro Abate, Julian Gutierrez +1

In this paper, we study the problem of learning to satisfy temporal logic specifications with a group of agents in an unknown environment, which may exhibit probabilistic behaviour…

cs.AI2018★ 4 cited

Learning Tractable Probabilistic Models for Moral Responsibility and Blame

Lewis Hammond, Vaishak Belle

Moral responsibility is a major concern in autonomous systems, with applications ranging from self-driving cars to kidney exchanges. Although there have been recent attempts to for…