# Robust Entropy-regularized Markov Decision Processes

arXiv: https://arxiv.org/abs/2112.15364 · HTML: https://mlsanity.com/paper/2112.15364/

## Key facts

- Cited by 4 papers in the map (data through 14 Oct 2026).
- Placed in Offline RL algorithms, one of 13 directions in Offline RL and imitation learning from data.
- Builds on 18 of its 38 references that are in the map.
- First posted on arXiv 31 Dec 2021.

## Placed in

- Offline RL and imitation learning from data / [Offline RL algorithms](https://mlsanity.com/offlinerl/offline-rl-algorithms/)

## Builds on (most cited first, 18 of 18)

- [Soft Actor-Critic: Off-Policy Maximum Entropy Deep Reinforcement Learning with a Stochastic Actor](https://mlsanity.com/paper/1801.01290/) (2018)
- [Trust Region Policy Optimization](https://mlsanity.com/paper/1502.05477/) (2015)
- [Generative Adversarial Imitation Learning](https://mlsanity.com/paper/1606.03476/) (2016)
- [Soft Actor-Critic Algorithms and Applications](https://mlsanity.com/paper/1812.05905/) (2018)
- [Reinforcement Learning with Deep Energy-Based Policies](https://mlsanity.com/paper/1702.08165/) (2017)
- [Learning Robust Rewards with Adversarial Inverse Reinforcement Learning](https://mlsanity.com/paper/1710.11248/) (2017)
- [Maximum a Posteriori Policy Optimisation](https://mlsanity.com/paper/1806.06920/) (2018)
- [A Theory of Regularized Markov Decision Processes](https://mlsanity.com/paper/1901.11275/) (2019)
- [Equivalence Between Policy Gradients and Soft Q-Learning](https://mlsanity.com/paper/1704.06440/) (2017)
- [Taming the Noise in Reinforcement Learning via Soft Updates](https://mlsanity.com/paper/1512.08562/) (2015)
- [Robust Reinforcement Learning for Continuous Control with Model Misspecification](https://mlsanity.com/paper/1906.07516/) (2019)
- [Multi-Agent Adversarial Inverse Reinforcement Learning](https://mlsanity.com/paper/1907.13220/) (2019)
- [Sparse Markov Decision Processes with Causal Sparse Tsallis Entropy Regularization for Reinforcement Learning](https://mlsanity.com/paper/1709.06293/) (2017)
- [Robust Inverse Reinforcement Learning under Transition Dynamics Mismatch](https://mlsanity.com/paper/2007.01174/) (2020)
- [Relative Entropy Regularized Policy Iteration](https://mlsanity.com/paper/1812.02256/) (2018)
- [If MaxEnt RL is the Answer, What is the Question?](https://mlsanity.com/paper/1910.01913/) (2019)
- [Frank-Wolfe Algorithms for Saddle Point Problems](https://mlsanity.com/paper/1610.07797/) (2016)
- [An Ordinal Minimax Theorem](https://mlsanity.com/paper/1412.4198/) (2014)

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

- [Efficient Policy Iteration for Robust Markov Decision Processes via Regularization](https://mlsanity.com/paper/2205.14327/) (2022)
- [Near-Optimal Policy Identification in Robust Constrained Markov Decision Processes via Epigraph Form](https://mlsanity.com/paper/2408.16286/) (2024)
- [An Efficient Solution to s-Rectangular Robust Markov Decision Processes](https://mlsanity.com/paper/2301.13642/) (2023)
- [Provably Efficient Algorithms for S- and Non-Rectangular Robust MDPs with General Parameterization](https://mlsanity.com/paper/2602.11387/) (2026)

## Abstract (arXiv)

Stochastic and soft optimal policies resulting from entropy-regularized Markov decision processes (ER-MDP) are desirable for exploration and imitation learning applications. Motivated by the fact that such policies are sensitive with respect to the state transition probabilities, and the estimation of these probabilities may be inaccurate, we study a robust version of the ER-MDP model, where the stochastic optimal policies are required to be robust with respect to the ambiguity in the underlying transition probabilities. Our work is at the crossroads of two important schemes in reinforcement learning (RL), namely, robust MDP and entropy regularized MDP. We show that essential properties that hold for the non-robust ER-MDP and robust unregularized MDP models also hold in our settings, making the robust ER-MDP problem tractable. We show how our framework and results can be integrated into different algorithmic schemes including value or (modified) policy iteration, which would lead to new robust RL and inverse RL algorithms to handle uncertainties. Analyses on computational complexity and error propagation under conventional uncertainty settings are also provided.
