# Near-Optimal Sample Complexity Bounds for Constrained Average-Reward MDPs

arXiv: https://arxiv.org/abs/2509.16586 · HTML: https://mlsanity.com/paper/2509.16586/

## Key facts

- Cited by 4 papers in the map (data through 14 Oct 2026).
- Builds on 21 of its 41 references that are in the map.
- First posted on arXiv 20 Sep 2025.

## Builds on (most cited first, 21 of 21)

- [Training language models to follow instructions with human feedback](https://mlsanity.com/paper/2203.02155/) (2022)
- [DeepSeekMath: Pushing the Limits of Mathematical Reasoning in Open Language Models](https://mlsanity.com/paper/2402.03300/) (2024)
- [Sim-to-Real: Learning Agile Locomotion For Quadruped Robots](https://mlsanity.com/paper/1804.10332/) (2018)
- [Constrained Reinforcement Learning Has Zero Duality Gap](https://mlsanity.com/paper/1910.13393/) (2019)
- [Exploration-Exploitation in Constrained MDPs](https://mlsanity.com/paper/2003.02189/) (2020)
- [TossingBot: Learning to Throw Arbitrary Objects with Residual Physics](https://mlsanity.com/paper/1903.11239/) (2019)
- [Provably Efficient Safe Exploration via Primal-Dual Policy Optimization](https://mlsanity.com/paper/2003.00534/) (2020)
- [Model-Based Reinforcement Learning with a Generative Model is Minimax Optimal](https://mlsanity.com/paper/1906.03804/) (2019)
- [Breaking the Sample Size Barrier in Model-Based Reinforcement Learning with a Generative Model](https://mlsanity.com/paper/2005.12900/) (2020)
- [Achieving Zero Constraint Violation for Constrained Reinforcement Learning via Primal-Dual Approach](https://mlsanity.com/paper/2109.06332/) (2021)
- [Constrained Upper Confidence Reinforcement Learning](https://mlsanity.com/paper/2001.09377/) (2020)
- [Upper Confidence Primal-Dual Reinforcement Learning for CMDP with Adversarial Loss](https://mlsanity.com/paper/2003.00660/) (2020)
- [Near-Optimal Sample Complexity Bounds for Constrained MDPs](https://mlsanity.com/paper/2206.06270/) (2022)
- [Constrained episodic reinforcement learning in concave-convex and knapsack settings](https://mlsanity.com/paper/2006.05051/) (2020)
- [A Sample-Efficient Algorithm for Episodic Finite-Horizon MDP with Constraints](https://mlsanity.com/paper/2009.11348/) (2020)
- [A Simple Reward-free Approach to Constrained Reinforcement Learning](https://mlsanity.com/paper/2107.05216/) (2021)
- [Near Sample-Optimal Reduction-based Policy Learning for Average Reward MDP](https://mlsanity.com/paper/2212.00603/) (2022)
- [Provably Efficient Algorithms for Multi-Objective Competitive RL](https://mlsanity.com/paper/2102.03192/) (2021)
- [A Provably-Efficient Model-Free Algorithm for Constrained Markov Decision Processes](https://mlsanity.com/paper/2106.01577/) (2021)
- [Span-Based Optimal Sample Complexity for Weakly Communicating and General Average Reward MDPs](https://mlsanity.com/paper/2403.11477/) (2024)
- [Learning General Parameterized Policies for Infinite Horizon Average Reward Constrained MDPs via Primal-Dual Policy Gradient Algorithm](https://mlsanity.com/paper/2402.02042/) (2024)

## Built on by (most cited first, 4 of 4)

- [Near-Optimal Primal-Dual Algorithm for Learning Linear Mixture CMDPs with Adversarial Rewards](https://mlsanity.com/paper/2603.27884/) (2026)
- [Learning Weakly Communicating Average-Reward CMDPs: Strong Duality and Improved Regret](https://mlsanity.com/paper/2605.11586/) (2026)
- [Near-Optimal Reinforcement Learning for Constrained Recurrence Objectives](https://mlsanity.com/paper/2511.19849/) (2025)
- [Instance-Dependent Regret for CMDPs with Step-Wise Constraints](https://mlsanity.com/paper/2610.02520/) (2026)

## Abstract (arXiv)

Recent advances have significantly improved our understanding of the sample complexity of learning in average-reward Markov decision processes (AMDPs) under the generative model. However, much less is known about the constrained average-reward MDP (CAMDP), where policies must satisfy long-run average constraints. In this work, we address this gap by studying the sample complexity of learning an ε-optimal policy in CAMDPs under a generative model. We propose a model-based algorithm that operates under two settings: (i) relaxed feasibility, which allows small constraint violations, and (ii) strict feasibility, where the output policy satisfies the constraint. We show that our algorithm achieves sample complexities of tildeOleft(fracS A (B+H) ε2right) and tildeO left(fracS A (B+H)ε2 zeta2 right) under the relaxed and strict feasibility settings, respectively. Here, zeta is the Slater constant indicating the size of the feasible region, H is the span bound of the bias function, and B is the transient time bound. Moreover, a matching lower bound of tildeOmegaleft(fracS A (B+H) ε2zeta2right) for the strict feasibility case is established, thus providing the first minimax-optimal bounds for CAMDPs. Our results close the theoretical gap in understanding the complexity of constrained average-reward MDPs.
