# Value Mirror Descent for Reinforcement Learning

arXiv: https://arxiv.org/abs/2604.06039 · HTML: https://mlsanity.com/paper/2604.06039/

## Key facts

- Cited by 1 papers in the map (data through 14 Oct 2026).
- Placed in RL theory and sample complexity, one of 15 directions in Deep reinforcement learning methods.
- Builds on 23 of its 38 references that are in the map.
- First posted on arXiv 7 Apr 2026.

## Placed in

- Deep reinforcement learning methods / [RL theory and sample complexity](https://mlsanity.com/deeprl/rl-theory-and-sample-complexity/)

## Builds on (most cited first, 23 of 23)

- [Proximal Policy Optimization Algorithms](https://mlsanity.com/paper/1707.06347/) (2017)
- [Trust Region Policy Optimization](https://mlsanity.com/paper/1502.05477/) (2015)
- [Reinforcement Learning with Deep Energy-Based Policies](https://mlsanity.com/paper/1702.08165/) (2017)
- [A Theory of Regularized Markov Decision Processes](https://mlsanity.com/paper/1901.11275/) (2019)
- [Policy Mirror Descent for Reinforcement Learning: Linear Convergence, New Sampling Complexity, and Generalized Problem Classes](https://mlsanity.com/paper/2102.00135/) (2021)
- [Model-Based Reinforcement Learning with a Generative Model is Minimax Optimal](https://mlsanity.com/paper/1906.03804/) (2019)
- [Policy Mirror Descent for Regularized Reinforcement Learning: A Generalized Framework with Linear Convergence](https://mlsanity.com/paper/2105.11066/) (2021)
- [Variance Reduced Value Iteration and Faster Algorithms for Solving Markov Decision Processes](https://mlsanity.com/paper/1710.09988/) (2017)
- [Simple and optimal methods for stochastic variational inequalities, I: operator extrapolation](https://mlsanity.com/paper/2011.02987/) (2020)
- [Primal-Dual π Learning: Sample Complexity and Sublinear Run Time for Ergodic Markov Decision Problems](https://mlsanity.com/paper/1710.06100/) (2017)
- [Leverage the Average: an Analysis of KL Regularization in RL](https://mlsanity.com/paper/2003.14089/) (2020)
- [Stochastic first-order methods for average-reward Markov decision processes](https://mlsanity.com/paper/2205.05800/) (2022)
- [First-order Policy Optimization for Robust Markov Decision Process](https://mlsanity.com/paper/2209.10579/) (2022)
- [Policy Optimization over General State and Action Spaces](https://mlsanity.com/paper/2211.16715/) (2022)
- [Accelerated and instance-optimal policy evaluation with linear function approximation](https://mlsanity.com/paper/2112.13109/) (2021)
- [Stochastic Primal-Dual Methods and Sample Complexity of Reinforcement Learning](https://mlsanity.com/paper/1612.02516/) (2016)
- [KL-Entropy-Regularized RL with a Generative Model is Minimax Optimal](https://mlsanity.com/paper/2205.14211/) (2022)
- [Policy Mirror Descent Inherently Explores Action Space](https://mlsanity.com/paper/2303.04386/) (2023)
- [Optimistically Optimistic Exploration for Provably Efficient Infinite-Horizon Reinforcement and Imitation Learning](https://mlsanity.com/paper/2502.13900/) (2025)
- [Optimistic Planning by Regularized Dynamic Programming](https://mlsanity.com/paper/2302.14004/) (2023)
- [Strongly-polynomial time and validation analysis of policy gradient methods](https://mlsanity.com/paper/2409.19437/) (2024)
- [Auto-exploration for online reinforcement learning](https://mlsanity.com/paper/2512.06244/) (2025)
- [Policy Mirror Descent with Temporal Difference Learning: Sample Complexity under Online Markov Data](https://mlsanity.com/paper/2512.24056/) (2025)

## Built on by (most cited first, 1 of 1)

- [Fast Regularized Policy Mirror Descent with One-Step TD Updates](https://mlsanity.com/paper/2609.39837/) (2026)

## Abstract (arXiv)

Value iteration-type methods have been extensively studied for computing a nearly optimal value function in reinforcement learning (RL). Under a generative sampling model, these methods can achieve sharper sample complexity than policy optimization approaches, particularly in their dependence on the discount factor. In practice, they are often employed for offline training. In this paper, we consider discounted Markov decision processes with state space S, action space A, discount factor γ∈(0,1) and costs in [0,1]. We introduce a novel value optimization method, termed value mirror descent (VMD), which integrates mirror descent from convex optimization into the classical value iteration framework. In the deterministic setting with known transition kernels, we show that VMD converges linearly. For the stochastic setting with a generative model, we develop a stochastic variant, SVMD, which incorporates variance reduction commonly used in stochastic value iteration-type methods. For RL problems with general convex regularizers, SVMD attains a near-optimal sample complexity of tildeO(|S||A|(1-γ)-3ε-2). Moreover, we establish that the Bregman divergence between the generated and optimal policies remains bounded throughout the iterations, even under the presence of model misspecification. This property is absent in existing stochastic value iteration-type methods but is important for enabling effective online (continual) learning following offline training. Under a strongly convex regularizer, SVMD achieves sample complexity of tildeO(|S||A|(1-γ)-5ε-1), improving performance in the high-accuracy regime. Furthermore, we prove convergence of the generated policy to the optimal policy. Overall, the proposed method, its analysis, and the resulting guarantees, constitute new contributions to the RL and optimization literature.
