# Overcoming the Curse of Dimensionality in Reinforcement Learning Through Approximate Factorization

arXiv: https://arxiv.org/abs/2411.07591 · HTML: https://mlsanity.com/paper/2411.07591/

## Key facts

- Cited by 6 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 11 of its 65 references that are in the map.
- First posted on arXiv 12 Nov 2024.

## 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, 11 of 11)

- [Provably Efficient Reinforcement Learning with Linear Function Approximation](https://mlsanity.com/paper/1907.05388/) (2019)
- [Breaking the Sample Size Barrier in Model-Based Reinforcement Learning with a Generative Model](https://mlsanity.com/paper/2005.12900/) (2020)
- [Is Q-Learning Minimax Optimal? A Tight Sample Complexity Analysis](https://mlsanity.com/paper/2102.06548/) (2021)
- [Stochastic approximation with cone-contractive operators: Sharp ℓ_∞-bounds for Q-learning](https://mlsanity.com/paper/1905.06265/) (2019)
- [Variance-reduced Q-learning is minimax optimal](https://mlsanity.com/paper/1906.04697/) (2019)
- [The Curious Price of Distributional Robustness in Reinforcement Learning with a Generative Model](https://mlsanity.com/paper/2305.16589/) (2023)
- [A Finite-Time Analysis of Q-Learning with Neural Network Function Approximation](https://mlsanity.com/paper/1912.04511/) (2019)
- [Efficient Reinforcement Learning in Factored MDPs with Application to Constrained RL](https://mlsanity.com/paper/2008.13319/) (2020)
- [Sample Efficient Reinforcement Learning in Mixed Systems through Augmented Samples and Its Applications to Queueing Networks](https://mlsanity.com/paper/2305.16483/) (2023)
- [SBEED: Convergent Reinforcement Learning with Nonlinear Function Approximation](https://mlsanity.com/paper/1712.10285/) (2017)
- [A General Control-Theoretic Approach for Reinforcement Learning: Theory and Algorithms](https://mlsanity.com/paper/2406.14753/) (2024)

## Built on by (most cited first, 6 of 6)

- [Interactive Imitation Learning for Dexterous Robotic Manipulation: Challenges and Perspectives -- A Survey](https://mlsanity.com/paper/2506.00098/) (2025)
- [Reinforcement Learning with Imperfect Transition Predictions: A Bellman-Jensen Approach](https://mlsanity.com/paper/2510.18687/) (2025)
- [Structured Cooperative Multi-Agent Reinforcement Learning: a Bayesian Network Perspective](https://mlsanity.com/paper/2510.09937/) (2025)
- [Tensor-Efficient High-Dimensional Q-learning](https://mlsanity.com/paper/2511.03595/) (2025)
- [COOL-MC: Verifying and Explaining RL Policies for Multi-bridge Network Maintenance](https://mlsanity.com/paper/2603.07546/) (2026)
- [Learning to Play Blackjack: A Curriculum Learning Perspective](https://mlsanity.com/paper/2604.00076/) (2026)

## Abstract (arXiv)

Reinforcement Learning (RL) algorithms are known to suffer from the curse of dimensionality, which refers to the fact that large-scale problems often lead to exponentially high sample complexity. A common solution is to use deep neural networks for function approximation; however, such approaches typically lack theoretical guarantees. To provably address the curse of dimensionality, we observe that many real-world problems exhibit task-specific model structures that, when properly leveraged, can improve the sample efficiency of RL. Building on this insight, we propose overcoming the curse of dimensionality by approximately factorizing the original Markov decision processes (MDPs) into smaller, independently evolving MDPs. This factorization enables the development of sample-efficient RL algorithms in both model-based and model-free settings, with the latter involving a variant of variance-reduced Q-learning. We provide improved sample complexity guarantees for both proposed algorithms. Notably, by leveraging model structure through the approximate factorization of the MDP, the dependence of sample complexity on the size of the state-action space can be exponentially reduced. Numerically, we demonstrate the practicality of our proposed methods through experiments on both synthetic MDP tasks and a wind farm-equipped storage control problem.
