# Generating Teammates for Training Robust Ad Hoc Teamwork Agents via Best-Response Diversity

arXiv: https://arxiv.org/abs/2207.14138 · HTML: https://mlsanity.com/paper/2207.14138/

## Key facts

- Cited by 17 papers in the map (data through 14 Oct 2026).
- Builds on 27 of its 39 references that are in the map.
- First posted on arXiv 28 Jul 2022.

## Builds on (most cited first, 27 of 27)

- [Adam: A Method for Stochastic Optimization](https://mlsanity.com/paper/1412.6980/) (2014)
- [Asynchronous Methods for Deep Reinforcement Learning](https://mlsanity.com/paper/1602.01783/) (2016)
- [Curiosity-driven Exploration by Self-supervised Prediction](https://mlsanity.com/paper/1705.05363/) (2017)
- [Deep Reinforcement Learning at the Edge of the Statistical Precipice](https://mlsanity.com/paper/2108.13264/) (2021)
- [Diversity is All You Need: Learning Skills without a Reward Function](https://mlsanity.com/paper/1802.06070/) (2018)
- [Multi-Agent Reinforcement Learning: A Selective Overview of Theories and Algorithms](https://mlsanity.com/paper/1911.10635/) (2019)
- [Population Based Training of Neural Networks](https://mlsanity.com/paper/1711.09846/) (2017)
- [The Complexity of Decentralized Control of Markov Decision Processes](https://mlsanity.com/paper/1301.3836/) (2013)
- [Benchmarking Multi-Agent Deep Reinforcement Learning Algorithms in Cooperative Tasks](https://mlsanity.com/paper/2006.07869/) (2020)
- ["Other-Play" for Zero-Shot Coordination](https://mlsanity.com/paper/2003.02979/) (2020)
- [MAVEN: Multi-Agent Variational Exploration](https://mlsanity.com/paper/1910.07483/) (2019)
- [Autonomous Agents Modelling Other Agents: A Comprehensive Survey and Open Problems](https://mlsanity.com/paper/1709.08071/) (2017)
- [Effective Diversity in Population Based Reinforcement Learning](https://mlsanity.com/paper/2002.00632/) (2020)
- [Celebrating Diversity in Shared Multi-Agent Reinforcement Learning](https://mlsanity.com/paper/2106.02195/) (2021)
- [Scaling Multi-Agent Reinforcement Learning with Selective Parameter Sharing](https://mlsanity.com/paper/2102.07475/) (2021)
- [Diversity-Driven Exploration Strategy for Deep Reinforcement Learning](https://mlsanity.com/paper/1802.04564/) (2018)
- [Agent Modelling under Partial Observability for Deep Reinforcement Learning](https://mlsanity.com/paper/2006.09447/) (2020)
- [A Game-Theoretic Model and Best-Response Learning Method for Ad Hoc Coordination in Multiagent Systems](https://mlsanity.com/paper/1506.01170/) (2015)
- [A Survey of Ad Hoc Teamwork Research](https://mlsanity.com/paper/2202.10450/) (2022)
- [Towards Open Ad Hoc Teamwork Using Graph-based Policy Learning](https://mlsanity.com/paper/2006.10412/) (2020)
- [Discovering Diverse Multi-Agent Strategic Behavior via Reward Randomization](https://mlsanity.com/paper/2103.04564/) (2021)
- [Too many cooks: Bayesian inference for coordinating multi-agent collaboration](https://mlsanity.com/paper/2003.11778/) (2020)
- [Deep Interactive Bayesian Reinforcement Learning via Meta-Learning](https://mlsanity.com/paper/2101.03864/) (2021)
- [Any-Play: An Intrinsic Augmentation for Zero-Shot Coordination](https://mlsanity.com/paper/2201.12436/) (2022)
- [A Generalized Framework for Population Based Training](https://mlsanity.com/paper/1902.01894/) (2019)
- [Belief and Truth in Hypothesised Behaviours](https://mlsanity.com/paper/1507.07688/) (2015)
- [Learning Task Embeddings for Teamwork Adaptation in Multi-Agent Reinforcement Learning](https://mlsanity.com/paper/2207.02249/) (2022)

## Built on by (most cited first, 17 of 17)

- [Cooperation on the Fly: Exploring Language Agents for Ad Hoc Teamwork in the Avalon Game](https://mlsanity.com/paper/2312.17515/) (2023)
- [ZSC-Eval: An Evaluation Toolkit and Benchmark for Multi-agent Zero-shot Coordination](https://mlsanity.com/paper/2310.05208/) (2023)
- [Minimum Coverage Sets for Training Robust Ad Hoc Teamwork Agents](https://mlsanity.com/paper/2308.09595/) (2023)
- [HyperMARL: Adaptive Hypernetworks for Multi-Agent RL](https://mlsanity.com/paper/2412.04233/) (2024)
- [MEAL: A Benchmark for Continual Multi-Agent Reinforcement Learning](https://mlsanity.com/paper/2506.14990/) (2025)
- [ROTATE: Regret-driven Open-ended Training for Ad Hoc Teamwork](https://mlsanity.com/paper/2505.23686/) (2025)
- [Role Play: Learning Adaptive Role-Specific Strategies in Multi-Agent Interactions](https://mlsanity.com/paper/2411.01166/) (2024)
- [Improving Human-AI Coordination through Online Adversarial Training and Generative Models](https://mlsanity.com/paper/2504.15457/) (2025)
- [Unsupervised Partner Design Enables Robust Ad-hoc Teamwork](https://mlsanity.com/paper/2508.06336/) (2025)
- [Symmetry-Breaking Augmentations for Ad Hoc Teamwork](https://mlsanity.com/paper/2402.09984/) (2024)
- [Robust and Diverse Multi-Agent Learning via Rational Policy Gradient](https://mlsanity.com/paper/2511.09535/) (2025)
- [Training Generalizable Collaborative Agents via Strategic Risk Aversion](https://mlsanity.com/paper/2602.21515/) (2026)
- [Benchmarking the Limits of In-Context Reinforcement Learning for Ad-Hoc Teamwork](https://mlsanity.com/paper/2605.24423/) (2026)
- [JaxAHT: A JAX-Based Library for Ad Hoc Teamwork](https://mlsanity.com/paper/2609.13716/) (2026)
- [Assistax: A Multi-Agent Hardware-Accelerated Reinforcement Learning Benchmark for Assistive Robotics](https://mlsanity.com/paper/2507.21638/) (2025)
- [Efficient Reinforcement Learning for Zero-Shot Coordination in Evolving Games](https://mlsanity.com/paper/2511.11083/) (2025)
- [Learning When to Cooperate Under Heterogeneous Goals](https://mlsanity.com/paper/2603.07253/) (2026)

## Abstract (arXiv)

Ad hoc teamwork (AHT) is the challenge of designing a robust learner agent that effectively collaborates with unknown teammates without prior coordination mechanisms. Early approaches address the AHT challenge by training the learner with a diverse set of handcrafted teammate policies, usually designed based on an expert's domain knowledge about the policies the learner may encounter. However, implementing teammate policies for training based on domain knowledge is not always feasible. In such cases, recent approaches attempted to improve the robustness of the learner by training it with teammate policies generated by optimising information-theoretic diversity metrics. The problem with optimising existing information-theoretic diversity metrics for teammate policy generation is the emergence of superficially different teammates. When used for AHT training, superficially different teammate behaviours may not improve a learner's robustness during collaboration with unknown teammates. In this paper, we present an automated teammate policy generation method optimising the Best-Response Diversity (BRDiv) metric, which measures diversity based on the compatibility of teammate policies in terms of returns. We evaluate our approach in environments with multiple valid coordination strategies, comparing against methods optimising information-theoretic diversity metrics and an ablation not optimising any diversity metric. Our experiments indicate that optimising BRDiv yields a diverse set of training teammate policies that improve the learner's performance relative to previous teammate generation approaches when collaborating with near-optimal previously unseen teammate policies.
