# FedHQL: Federated Heterogeneous Q-Learning

arXiv: https://arxiv.org/abs/2301.11135 · HTML: https://mlsanity.com/paper/2301.11135/

## Key facts

- Cited by 6 papers in the map (data through 14 Oct 2026).
- Builds on 22 of its 36 references that are in the map.
- First posted on arXiv 26 Jan 2023.

## Builds on (most cited first, 22 of 22)

- [Communication-Efficient Learning of Deep Networks from Decentralized Data](https://mlsanity.com/paper/1602.05629/) (2016)
- [Playing Atari with Deep Reinforcement Learning](https://mlsanity.com/paper/1312.5602/) (2013)
- [Advances and Open Problems in Federated Learning](https://mlsanity.com/paper/1912.04977/) (2019)
- [Asynchronous Methods for Deep Reinforcement Learning](https://mlsanity.com/paper/1602.01783/) (2016)
- [Decision Transformer: Reinforcement Learning via Sequence Modeling](https://mlsanity.com/paper/2106.01345/) (2021)
- [IMPALA: Scalable Distributed Deep-RL with Importance Weighted Actor-Learner Architectures](https://mlsanity.com/paper/1802.01561/) (2018)
- [The Future of Digital Health with Federated Learning](https://mlsanity.com/paper/2003.08119/) (2020)
- [Federated Optimization: Distributed Machine Learning for On-Device Intelligence](https://mlsanity.com/paper/1610.02527/) (2016)
- [Distributed Prioritized Experience Replay](https://mlsanity.com/paper/1803.00933/) (2018)
- [Stochastic Variance-Reduced Policy Gradient](https://mlsanity.com/paper/1806.05618/) (2018)
- [Massively Parallel Methods for Deep Reinforcement Learning](https://mlsanity.com/paper/1507.04296/) (2015)
- [Lifelong Federated Reinforcement Learning: A Learning Architecture for Navigation in Cloud Robotic Systems](https://mlsanity.com/paper/1901.06455/) (2019)
- [Boltzmann Exploration Done Right](https://mlsanity.com/paper/1705.10257/) (2017)
- [Federated Reinforcement Learning with Environment Heterogeneity](https://mlsanity.com/paper/2204.02634/) (2022)
- [Fault-Tolerant Federated Reinforcement Learning with Theoretical Guarantee](https://mlsanity.com/paper/2110.14074/) (2021)
- [Federated Transfer Reinforcement Learning for Autonomous Driving](https://mlsanity.com/paper/1910.06001/) (2019)
- [Federated Deep Reinforcement Learning](https://mlsanity.com/paper/1901.08277/) (2019)
- [When Deep Reinforcement Learning Meets Federated Learning: Intelligent Multi-Timescale Resource Management for Multi-access Edge Computing in 5G Ultra Dense Network](https://mlsanity.com/paper/2009.10601/) (2020)
- [Federated Stochastic Approximation under Markov Noise and Heterogeneity: Applications in Reinforcement Learning](https://mlsanity.com/paper/2206.10185/) (2022)
- [Collective Robot Reinforcement Learning with Distributed Asynchronous Guided Policy Search](https://mlsanity.com/paper/1610.00673/) (2016)
- [Federated Neural Bandits](https://mlsanity.com/paper/2205.14309/) (2022)
- [Byzantine-Robust Online and Offline Distributed Reinforcement Learning](https://mlsanity.com/paper/2206.00165/) (2022)

## Built on by (most cited first, 6 of 6)

- [Action and Trajectory Planning for Urban Autonomous Driving with Hierarchical Reinforcement Learning](https://mlsanity.com/paper/2306.15968/) (2023)
- [Gap-Dependent Bounds for Federated Q-learning](https://mlsanity.com/paper/2502.02859/) (2025)
- [Regret-Optimal Q-Learning with Low Cost for Single-Agent and Federated Reinforcement Learning](https://mlsanity.com/paper/2506.04626/) (2025)
- [Position Paper: Rethinking Privacy in RL for Sequential Decision-making in the Age of LLMs](https://mlsanity.com/paper/2504.11511/) (2025)
- [Approximated Behavioral Metric-based State Projection for Federated Reinforcement Learning](https://mlsanity.com/paper/2505.09959/) (2025)
- [Constraint-Aware Aggregation for Federated Reinforcement Learning in Microgrid Energy Coordination](https://mlsanity.com/paper/2607.12763/) (2026)

## Abstract (arXiv)

Federated Reinforcement Learning (FedRL) encourages distributed agents to learn collectively from each other's experience to improve their performance without exchanging their raw trajectories. The existing work on FedRL assumes that all participating agents are homogeneous, which requires all agents to share the same policy parameterization (e.g., network architectures and training configurations). However, in real-world applications, agents are often in disagreement about the architecture and the parameters, possibly also because of disparate computational budgets. Because homogeneity is not given in practice, we introduce the problem setting of Federated Reinforcement Learning with Heterogeneous And bLack-box agEnts (FedRL-HALE). We present the unique challenges this new setting poses and propose the Federated Heterogeneous Q-Learning (FedHQL) algorithm that principally addresses these challenges. We empirically demonstrate the efficacy of FedHQL in boosting the sample efficiency of heterogeneous agents with distinct policy parameterization using standard RL tasks.
