# Beating Adversarial Low-Rank MDPs with Unknown Transition and Bandit Feedback

arXiv: https://arxiv.org/abs/2411.06739 · HTML: https://mlsanity.com/paper/2411.06739/

## Key facts

- Cited by 2 papers in the map (data through 14 Oct 2026).
- Builds on 28 of its 44 references that are in the map.
- First posted on arXiv 11 Nov 2024.

## Builds on (most cited first, 28 of 28)

- [Provably Efficient Reinforcement Learning with Linear Function Approximation](https://mlsanity.com/paper/1907.05388/) (2019)
- [FLAMBE: Structural Complexity and Representation Learning of Low Rank MDPs](https://mlsanity.com/paper/2006.10814/) (2020)
- [Bellman Eluder Dimension: New Rich Classes of RL Problems, and Sample-Efficient Algorithms](https://mlsanity.com/paper/2102.00815/) (2021)
- [The Statistical Complexity of Interactive Decision Making](https://mlsanity.com/paper/2112.13487/) (2021)
- [Representation Learning for Online and Offline RL in Low-rank MDPs](https://mlsanity.com/paper/2110.04652/) (2021)
- [The Role of Coverage in Online Reinforcement Learning](https://mlsanity.com/paper/2210.04157/) (2022)
- [Policy Optimization in Adversarial MDPs: Improved Exploration via Dilated Bonuses](https://mlsanity.com/paper/2107.08346/) (2021)
- [Making Linear MDPs Practical via Contrastive Representation Learning](https://mlsanity.com/paper/2207.07150/) (2022)
- [Efficient Reinforcement Learning in Block MDPs: A Model-free Representation Learning Approach](https://mlsanity.com/paper/2202.00063/) (2022)
- [GEC: A Unified Framework for Interactive Decision Making in MDP, POMDP, and Beyond](https://mlsanity.com/paper/2211.01962/) (2022)
- [The best of both worlds: stochastic and adversarial episodic MDPs with unknown transition](https://mlsanity.com/paper/2106.04117/) (2021)
- [On the Complexity of Adversarial Decision Making](https://mlsanity.com/paper/2206.13063/) (2022)
- [Near-optimal Policy Optimization Algorithms for Learning Adversarial Linear Mixture MDPs](https://mlsanity.com/paper/2102.08940/) (2021)
- [On the Statistical Efficiency of Reward-Free Exploration in Non-Linear RL](https://mlsanity.com/paper/2206.10770/) (2022)
- [A Free Lunch from the Noise: Provable and Practical Exploration for Representation Learning](https://mlsanity.com/paper/2111.11485/) (2021)
- [Refined Regret for Adversarial MDPs with Linear Function Approximation](https://mlsanity.com/paper/2301.12942/) (2023)
- [Reinforcement Learning in Low-Rank MDPs with Density Features](https://mlsanity.com/paper/2302.02252/) (2023)
- [Follow-the-Perturbed-Leader for Adversarial Markov Decision Processes with Bandit Feedback](https://mlsanity.com/paper/2205.13451/) (2022)
- [Improved Regret for Efficient Online Reinforcement Learning with Linear Function Approximation](https://mlsanity.com/paper/2301.13087/) (2023)
- [Best of Both Worlds Policy Optimization](https://mlsanity.com/paper/2302.09408/) (2023)
- [Efficient Model-Free Exploration in Low-Rank MDPs](https://mlsanity.com/paper/2307.03997/) (2023)
- [Improved Regret Bounds for Linear Adversarial MDPs via Linear Optimization](https://mlsanity.com/paper/2302.06834/) (2023)
- [Improved Sample Complexity for Reward-free Reinforcement Learning under Low-rank MDPs](https://mlsanity.com/paper/2303.10859/) (2023)
- [Rate-Optimal Policy Optimization for Linear Markov Decision Processes](https://mlsanity.com/paper/2308.14642/) (2023)
- [The Power of Resets in Online Reinforcement Learning](https://mlsanity.com/paper/2404.15417/) (2024)
- [Towards Optimal Regret in Adversarial Linear MDPs with Bandit Feedback](https://mlsanity.com/paper/2310.11550/) (2023)
- [Unified Algorithms for RL with Decision-Estimation Coefficients: PAC, Reward-Free, Preference-Based Learning, and Beyond](https://mlsanity.com/paper/2209.11745/) (2022)
- [Learning Adversarial Low-rank Markov Decision Processes with Unknown Transition and Full-information Feedback](https://mlsanity.com/paper/2311.07876/) (2023)

## Built on by (most cited first, 2 of 2)

- [Decision Making in Hybrid Environments: A Model Aggregation Approach](https://mlsanity.com/paper/2502.05974/) (2025)
- [An Improved Model-Free Decision-Estimation Coefficient with Applications in Adversarial MDPs](https://mlsanity.com/paper/2510.08882/) (2025)

## Abstract (arXiv)

We consider regret minimization in low-rank MDPs with fixed transition and adversarial losses. Previous work has investigated this problem under either full-information loss feedback with unknown transitions (Zhao et al., 2024), or bandit loss feedback with known transition (Foster et al., 2022). First, we improve the poly(d, A, H)T5/6 regret bound of Zhao et al. (2024) to poly(d, A, H)T2/3 for the full-information unknown transition setting, where d is the rank of the transitions, A is the number of actions, H is the horizon length, and T is the number of episodes. Next, we initiate the study on the setting with bandit loss feedback and unknown transitions. Assuming that the loss has a linear structure, we propose both model based and model free algorithms achieving poly(d, A, H)T2/3 regret, though they are computationally inefficient. We also propose oracle-efficient model-free algorithms with poly(d, A, H)T4/5 regret. We show that the linear structure is necessary for the bandit case without structure on the reward function, the regret has to scale polynomially with the number of states. This is contrary to the full-information case (Zhao et al., 2024), where the regret can be independent of the number of states even for unstructured reward function.
