# Provable Reinforcement Learning with a Short-Term Memory

arXiv: https://arxiv.org/abs/2202.03983 · HTML: https://mlsanity.com/paper/2202.03983/

## Key facts

- Cited by 40 papers in the map (data through 14 Oct 2026).
- Builds on 24 of its 46 references that are in the map.
- First posted on arXiv 8 Feb 2022.

## Builds on (most cited first, 24 of 24)

- [Playing Atari with Deep Reinforcement Learning](https://mlsanity.com/paper/1312.5602/) (2013)
- [Dream to Control: Learning Behaviors by Latent Imagination](https://mlsanity.com/paper/1912.01603/) (2019)
- [Rainbow: Combining Improvements in Deep Reinforcement Learning](https://mlsanity.com/paper/1710.02298/) (2017)
- [Minimax Regret Bounds for Reinforcement Learning](https://mlsanity.com/paper/1703.05449/) (2017)
- [Deep Recurrent Q-Learning for Partially Observable MDPs](https://mlsanity.com/paper/1507.06527/) (2015)
- [Contextual Decision Processes with Low Bellman Rank are PAC-Learnable](https://mlsanity.com/paper/1610.09512/) (2016)
- [Information-Theoretic Considerations in Batch Reinforcement Learning](https://mlsanity.com/paper/1905.00360/) (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)
- [Bilinear Classes: A Structural Framework for Provable Generalization in RL](https://mlsanity.com/paper/2103.10897/) (2021)
- [Provably efficient RL with Rich Observations via Latent State Decoding](https://mlsanity.com/paper/1901.09018/) (2019)
- [Representation Learning for Online and Offline RL in Low-rank MDPs](https://mlsanity.com/paper/2110.04652/) (2021)
- [Deep Variational Reinforcement Learning for POMDPs](https://mlsanity.com/paper/1806.02426/) (2018)
- [Provably Efficient Reinforcement Learning with Linear Function Approximation Under Adaptivity Constraints](https://mlsanity.com/paper/2101.02195/) (2021)
- [Kinematic State Abstraction and Provably Efficient Rich-Observation Reinforcement Learning](https://mlsanity.com/paper/1911.05815/) (2019)
- [Online Control with Adversarial Disturbances](https://mlsanity.com/paper/1902.08721/) (2019)
- [Non-asymptotic Identification of LTI Systems from a Single Trajectory](https://mlsanity.com/paper/1806.05722/) (2018)
- [Exponential Lower Bounds for Planning in MDPs With Linearly-Realizable Optimal Action-Value Functions](https://mlsanity.com/paper/2010.01374/) (2020)
- [Sample-Efficient Reinforcement Learning of Undercomplete POMDPs](https://mlsanity.com/paper/2006.12484/) (2020)
- [Learning Linear Dynamical Systems with Semi-Parametric Least Squares](https://mlsanity.com/paper/1902.00768/) (2019)
- [Reinforcement Learning of POMDPs using Spectral Methods](https://mlsanity.com/paper/1602.07764/) (2016)
- [On Improving Deep Reinforcement Learning for POMDPs](https://mlsanity.com/paper/1804.06309/) (2018)
- [A PAC RL Algorithm for Episodic POMDPs](https://mlsanity.com/paper/1605.08062/) (2016)

## Built on by (most cited first, 30 of 40)

- [When Is Partially Observable Reinforcement Learning Not Scary?](https://mlsanity.com/paper/2204.08967/) (2022)
- [PAC Reinforcement Learning for Predictive State Representations](https://mlsanity.com/paper/2207.05738/) (2022)
- [Provably Efficient Reinforcement Learning in Partially Observable Dynamical Systems](https://mlsanity.com/paper/2206.12020/) (2022)
- [Learning in Observable POMDPs, without Computationally Intractable Oracles](https://mlsanity.com/paper/2206.03446/) (2022)
- [Pessimism in the Face of Confounders: Provably Efficient Offline Reinforcement Learning in Partially Observable Markov Decision Processes](https://mlsanity.com/paper/2205.13589/) (2022)
- [Partially Observable RL with B-Stability: Unified Structural Condition and Sharp Sample-Efficient Algorithms](https://mlsanity.com/paper/2209.14990/) (2022)
- [Learning in POMDPs is Sample-Efficient with Hindsight Observability](https://mlsanity.com/paper/2301.13857/) (2023)
- [Embed to Control Partially Observed Systems: Representation Learning with Provable Sample Efficiency](https://mlsanity.com/paper/2205.13476/) (2022)
- [Lower Bounds for Learning in Revealing POMDPs](https://mlsanity.com/paper/2302.01333/) (2023)
- [Diffusion Spectral Representation for Reinforcement Learning](https://mlsanity.com/paper/2406.16121/) (2024)
- [Finite-Time Analysis of Natural Actor-Critic for POMDPs](https://mlsanity.com/paper/2202.09753/) (2022)
- [Provable Representation with Efficient Planning for Partial Observable Reinforcement Learning](https://mlsanity.com/paper/2311.12244/) (2023)
- [On the Curses of Future and History in Future-dependent Value Functions for Off-policy Evaluation](https://mlsanity.com/paper/2402.14703/) (2024)
- [Partially Observable Reinforcement Learning with Memory Traces](https://mlsanity.com/paper/2503.15200/) (2025)
- [Provably Efficient Representation Learning with Tractable Planning in Low-Rank POMDP](https://mlsanity.com/paper/2306.12356/) (2023)
- [Statistical Tractability of Off-policy Evaluation of History-dependent Policies in POMDPs](https://mlsanity.com/paper/2503.01134/) (2025)
- [Optimistic MLE -- A Generic Model-based Algorithm for Partially Observable Sequential Decision Making](https://mlsanity.com/paper/2209.14997/) (2022)
- [Provably Efficient UCB-type Algorithms For Learning Predictive State Representations](https://mlsanity.com/paper/2307.00405/) (2023)
- [RL in Latent MDPs is Tractable: Online Guarantees via Off-Policy Evaluation](https://mlsanity.com/paper/2406.01389/) (2024)
- [Reward-Mixing MDPs with a Few Latent Contexts are Learnable](https://mlsanity.com/paper/2210.02594/) (2022)
- [Sample-Efficient Learning of POMDPs with Multiple Observations In Hindsight](https://mlsanity.com/paper/2307.02884/) (2023)
- [Prospective Side Information for Latent MDPs](https://mlsanity.com/paper/2310.07596/) (2023)
- [Scalable Policy-Based RL Algorithms for POMDPs](https://mlsanity.com/paper/2510.06540/) (2025)
- [Near-Optimal Learning and Planning in Separated Latent MDPs](https://mlsanity.com/paper/2406.07920/) (2024)
- [Tractable Offline Learning of Regular Decision Processes](https://mlsanity.com/paper/2409.02747/) (2024)
- [Abstract Reward Processes: Leveraging State Abstraction for Consistent Off-Policy Evaluation](https://mlsanity.com/paper/2410.02172/) (2024)
- [Guided Policy Optimization under Partial Observability](https://mlsanity.com/paper/2505.15418/) (2025)
- [To Distill or Decide? Understanding the Algorithmic Trade-off in Partially Observable Reinforcement Learning](https://mlsanity.com/paper/2510.03207/) (2025)
- [Spectral Representation-based Reinforcement Learning](https://mlsanity.com/paper/2512.15036/) (2025)
- [Generalizing Multi-Step Inverse Models for Representation Learning to Finite-Memory POMDPs](https://mlsanity.com/paper/2404.14552/) (2024)

## Abstract (arXiv)

Real-world sequential decision making problems commonly involve partial observability, which requires the agent to maintain a memory of history in order to infer the latent states, plan and make good decisions. Coping with partial observability in general is extremely challenging, as a number of worst-case statistical and computational barriers are known in learning Partially Observable Markov Decision Processes (POMDPs). Motivated by the problem structure in several physical applications, as well as a commonly used technique known as "frame stacking", this paper proposes to study a new subclass of POMDPs, whose latent states can be decoded by the most recent history of a short length m. We establish a set of upper and lower bounds on the sample complexity for learning near-optimal policies for this class of problems in both tabular and rich-observation settings (where the number of observations is enormous). In particular, in the rich-observation setting, we develop new algorithms using a novel "moment matching" approach with a sample complexity that scales exponentially with the short length m rather than the problem horizon, and is independent of the number of observations. Our results show that a short-term memory suffices for reinforcement learning in these environments.
