# Action Noise in Off-Policy Deep Reinforcement Learning: Impact on Exploration and Performance

arXiv: https://arxiv.org/abs/2206.03787 · HTML: https://mlsanity.com/paper/2206.03787/

## Key facts

- Cited by 22 papers in the map (data through 14 Oct 2026).
- Builds on 29 of its 57 references that are in the map.
- First posted on arXiv 8 Jun 2022.

## Builds on (most cited first, 29 of 29)

- [Proximal Policy Optimization Algorithms](https://mlsanity.com/paper/1707.06347/) (2017)
- [Continuous control with deep reinforcement learning](https://mlsanity.com/paper/1509.02971/) (2015)
- [Trust Region Policy Optimization](https://mlsanity.com/paper/1502.05477/) (2015)
- [Addressing Function Approximation Error in Actor-Critic Methods](https://mlsanity.com/paper/1802.09477/) (2018)
- [OpenAI Gym](https://mlsanity.com/paper/1606.01540/) (2016)
- [D4RL: Datasets for Deep Data-Driven Reinforcement Learning](https://mlsanity.com/paper/2004.07219/) (2020)
- [Soft Actor-Critic Algorithms and Applications](https://mlsanity.com/paper/1812.05905/) (2018)
- [Exploration by Random Network Distillation](https://mlsanity.com/paper/1810.12894/) (2018)
- [DeepMind Control Suite](https://mlsanity.com/paper/1801.00690/) (2018)
- [QT-Opt: Scalable Deep Reinforcement Learning for Vision-Based Robotic Manipulation](https://mlsanity.com/paper/1806.10293/) (2018)
- [#Exploration: A Study of Count-Based Exploration for Deep Reinforcement Learning](https://mlsanity.com/paper/1611.04717/) (2016)
- [Skew-Fit: State-Covering Self-Supervised Reinforcement Learning](https://mlsanity.com/paper/1903.03698/) (2019)
- [Exploration in Deep Reinforcement Learning: A Survey](https://mlsanity.com/paper/2205.00824/) (2022)
- [Parameter Space Noise for Exploration](https://mlsanity.com/paper/1706.01905/) (2017)
- [Acme: A Research Framework for Distributed Reinforcement Learning](https://mlsanity.com/paper/2006.00979/) (2020)
- [Sample-efficient Cross-Entropy Method for Real-time Planning](https://mlsanity.com/paper/2008.06389/) (2020)
- [d3rlpy: An Offline Deep Reinforcement Learning Library](https://mlsanity.com/paper/2111.03788/) (2021)
- [Simple random search provides a competitive approach to reinforcement learning](https://mlsanity.com/paper/1803.07055/) (2018)
- [A Survey of Exploration Methods in Reinforcement Learning](https://mlsanity.com/paper/2109.00157/) (2021)
- [Smooth Exploration for Robotic Reinforcement Learning](https://mlsanity.com/paper/2005.05719/) (2020)
- [ChainerRL: A Deep Reinforcement Learning Library](https://mlsanity.com/paper/1912.03905/) (2019)
- [Leveraging exploration in off-policy algorithms via normalizing flows](https://mlsanity.com/paper/1905.06893/) (2019)
- [GEP-PG: Decoupling Exploration and Exploitation in Deep Reinforcement Learning Algorithms](https://mlsanity.com/paper/1802.05054/) (2018)
- [Improving Exploration in Soft-Actor-Critic with Normalizing Flows Policies](https://mlsanity.com/paper/1906.02771/) (2019)
- [Is Bang-Bang Control All You Need? Solving Continuous Control with Bernoulli Policies](https://mlsanity.com/paper/2111.02552/) (2021)
- [Task-Agnostic Exploration via Policy Gradient of a Non-Parametric State Entropy Estimate](https://mlsanity.com/paper/2007.04640/) (2020)
- [Direct Estimation of Information Divergence Using Nearest Neighbor Ratios](https://mlsanity.com/paper/1702.05222/) (2017)
- [How to Make Deep RL Work in Practice](https://mlsanity.com/paper/2010.13083/) (2020)
- [Taking the Scenic Route: Automatic Exploration for Videogames](https://mlsanity.com/paper/1812.03125/) (2018)

## Built on by (most cited first, 22 of 22)

- [Colored Noise in PPO: Improved Exploration and Performance through Correlated Action Sampling](https://mlsanity.com/paper/2312.11091/) (2023)
- [Learning to Explore with Parameter-Space Noise: A Deep Dive into Parameter-Space Noise for Reinforcement Learning with Verifiable Rewards](https://mlsanity.com/paper/2602.02555/) (2026)
- [FlashSAC: Fast and Stable Off-Policy Reinforcement Learning for High-Dimensional Robot Control](https://mlsanity.com/paper/2604.04539/) (2026)
- [ChronoDreamer: Action-Conditioned World Model as an Online Simulator for Robotic Planning](https://mlsanity.com/paper/2512.18619/) (2025)
- [Mitigating Off-Policy Bias in Actor-Critic Methods with One-Step Q-learning: A Novel Correction Approach](https://mlsanity.com/paper/2208.00755/) (2022)
- [Noisy Spiking Actor Network for Exploration](https://mlsanity.com/paper/2403.04162/) (2024)
- [Enhancing Reinforcement Learning in Sensor Fusion: A Comparative Analysis of Cubature and Sampling-based Integration Methods for Rover Search Planning](https://mlsanity.com/paper/2405.08691/) (2024)
- [Model-free reinforcement learning with noisy actions for automated experimental control in optics](https://mlsanity.com/paper/2405.15421/) (2024)
- [Mind Your Entropy: From Maximum Entropy to Trajectory Entropy-Constrained RL](https://mlsanity.com/paper/2511.11592/) (2025)
- [VLD: Visual Language Goal Distance for Reinforcement Learning Navigation](https://mlsanity.com/paper/2512.07976/) (2025)
- [λ-models: Effective Decision-Aware Reinforcement Learning with Latent Models](https://mlsanity.com/paper/2306.17366/) (2023)
- [Quantifying First-Order Markov Violations in Noisy Reinforcement Learning: A Causal Discovery Approach](https://mlsanity.com/paper/2503.00206/) (2025)
- [Combating Spatial Disorientation in a Dynamic Self-Stabilization Task Using AI Assistants](https://mlsanity.com/paper/2409.14565/) (2024)
- [Trajectory First: A Curriculum for Discovering Diverse Policies](https://mlsanity.com/paper/2506.01568/) (2025)
- [Quantum-Inspired DRL Approach with LSTM and OU Noise for Cut Order Planning Optimization](https://mlsanity.com/paper/2508.16611/) (2025)
- [GAPO: Robust Advantage Estimation for Real-World Code LLMs](https://mlsanity.com/paper/2510.21830/) (2025)
- [Optimizing Path Planning using Deep Reinforcement Learning for UGVs in Precision Agriculture](https://mlsanity.com/paper/2601.04668/) (2026)
- [120 Minutes and a Laptop: Minimalist Image-goal Navigation via Unsupervised Exploration and Offline RL](https://mlsanity.com/paper/2603.26441/) (2026)
- [Prediction-Based Markov Violation Scores for Detecting Non-Markovian Observations in Reinforcement Learning](https://mlsanity.com/paper/2603.27389/) (2026)
- [Infant Spontaneous Movement Noise Improves Exploration in Deep RL](https://mlsanity.com/paper/2606.16590/) (2026)
- [Improving Online Reinforcement Learning via Bidirectional Behavior Prior Distillation](https://mlsanity.com/paper/2609.20268/) (2026)
- [DexPolicy: Scheduled Exploration for Trajectory-Guided Dexterous Manipulation](https://mlsanity.com/paper/2610.00360/) (2026)

## Abstract (arXiv)

Many Deep Reinforcement Learning (D-RL) algorithms rely on simple forms of exploration such as the additive action noise often used in continuous control domains. Typically, the scaling factor of this action noise is chosen as a hyper-parameter and is kept constant during training. In this paper, we focus on action noise in off-policy deep reinforcement learning for continuous control. We analyze how the learned policy is impacted by the noise type, noise scale, and impact scaling factor reduction schedule. We consider the two most prominent types of action noise, Gaussian and Ornstein-Uhlenbeck noise, and perform a vast experimental campaign by systematically varying the noise type and scale parameter, and by measuring variables of interest like the expected return of the policy and the state-space coverage during exploration. For the latter, we propose a novel state-space coverage measure operatornameXUrel that is more robust to estimation artifacts caused by points close to the state-space boundary than previously-proposed measures. Larger noise scales generally increase state-space coverage. However, we found that increasing the space coverage using a larger noise scale is often not beneficial. On the contrary, reducing the noise scale over the training process reduces the variance and generally improves the learning performance. We conclude that the best noise type and scale are environment dependent, and based on our observations derive heuristic rules for guiding the choice of the action noise as a starting point for further optimization.
