# Maximum Entropy Reinforcement Learning with Mixture Policies

arXiv: https://arxiv.org/abs/2103.10176 · HTML: https://mlsanity.com/paper/2103.10176/

## Key facts

- Cited by 4 papers in the map (data through 14 Oct 2026).
- Builds on 15 of its 45 references that are in the map.
- First posted on arXiv 18 Mar 2021.

## Builds on (most cited first, 15 of 15)

- [Adam: A Method for Stochastic Optimization](https://mlsanity.com/paper/1412.6980/) (2014)
- [Soft Actor-Critic: Off-Policy Maximum Entropy Deep Reinforcement Learning with a Stochastic Actor](https://mlsanity.com/paper/1801.01290/) (2018)
- [Continuous control with deep reinforcement learning](https://mlsanity.com/paper/1509.02971/) (2015)
- [Addressing Function Approximation Error in Actor-Critic Methods](https://mlsanity.com/paper/1802.09477/) (2018)
- [Soft Actor-Critic Algorithms and Applications](https://mlsanity.com/paper/1812.05905/) (2018)
- [Deep Exploration via Bootstrapped DQN](https://mlsanity.com/paper/1602.04621/) (2016)
- [Learning Robust Rewards with Adversarial Inverse Reinforcement Learning](https://mlsanity.com/paper/1710.11248/) (2017)
- [SUNRISE: A Simple Unified Framework for Ensemble Learning in Deep Reinforcement Learning](https://mlsanity.com/paper/2007.04938/) (2020)
- [Averaged-DQN: Variance Reduction and Stabilization for Deep Reinforcement Learning](https://mlsanity.com/paper/1611.01929/) (2016)
- [OptionGAN: Learning Joint Reward-Policy Options using Generative Adversarial Inverse Reinforcement Learning](https://mlsanity.com/paper/1709.06683/) (2017)
- [An Optimistic Perspective on Offline Reinforcement Learning](https://mlsanity.com/paper/1907.04543/) (2019)
- [Estimating Mixture Entropy with Pairwise Distances](https://mlsanity.com/paper/1706.02419/) (2017)
- [Mix&Match - Agent Curricula for Reinforcement Learning](https://mlsanity.com/paper/1806.01780/) (2018)
- [Distributional Policy Optimization: An Alternative Approach for Continuous Control](https://mlsanity.com/paper/1905.09855/) (2019)
- [Optimistic Distributionally Robust Policy Optimization](https://mlsanity.com/paper/2006.07815/) (2020)

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

- [Near-optimal Conservative Exploration in Reinforcement Learning under Episode-wise Constraints](https://mlsanity.com/paper/2306.06265/) (2023)
- [How to Choose a Reinforcement-Learning Algorithm](https://mlsanity.com/paper/2407.20917/) (2024)
- [Design of Restricted Normalizing Flow towards Arbitrary Stochastic Policy with Computational Efficiency](https://mlsanity.com/paper/2412.12894/) (2024)
- [Revisiting Mixture Policies in Entropy-Regularized Actor-Critic](https://mlsanity.com/paper/2605.09157/) (2026)

## Abstract (arXiv)

Mixture models are an expressive hypothesis class that can approximate a rich set of policies. However, using mixture policies in the Maximum Entropy (MaxEnt) framework is not straightforward. The entropy of a mixture model is not equal to the sum of its components, nor does it have a closed-form expression in most cases. Using such policies in MaxEnt algorithms, therefore, requires constructing a tractable approximation of the mixture entropy. In this paper, we derive a simple, low-variance mixture-entropy estimator. We show that it is closely related to the sum of marginal entropies. Equipped with our entropy estimator, we derive an algorithmic variant of Soft Actor-Critic (SAC) to the mixture policy case and evaluate it on a series of continuous control tasks.
