# Tight Regret Bounds for Model-Based Reinforcement Learning with Greedy Policies

arXiv: https://arxiv.org/abs/1905.11527 · HTML: https://mlsanity.com/paper/1905.11527/

## Key facts

- Cited by 39 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 27 May 2019.

## Built on by (most cited first, 30 of 39)

- [Learning Policies with Zero or Bounded Constraint Violation for Constrained MDPs](https://mlsanity.com/paper/2106.02684/) (2021)
- [Unpacking Reward Shaping: Understanding the Benefits of Reward Engineering on Sample Complexity](https://mlsanity.com/paper/2210.09579/) (2022)
- [Near-Optimal Offline Reinforcement Learning via Double Variance Reduction](https://mlsanity.com/paper/2102.01748/) (2021)
- [Cautiously Optimistic Policy Optimization and Exploration with Linear Function Approximation](https://mlsanity.com/paper/2103.12923/) (2021)
- [Breaking the Sample Complexity Barrier to Regret-Optimal Model-Free Reinforcement Learning](https://mlsanity.com/paper/2110.04645/) (2021)
- [UCB Momentum Q-learning: Correcting the bias without forgetting](https://mlsanity.com/paper/2103.01312/) (2021)
- [Settling the Sample Complexity of Online Reinforcement Learning](https://mlsanity.com/paper/2307.13586/) (2023)
- [Efficient Model-Based Multi-Agent Mean-Field Reinforcement Learning](https://mlsanity.com/paper/2107.04050/) (2021)
- [Stochastic Shortest Path: Minimax, Parameter-Free and Towards Horizon-Free Regret](https://mlsanity.com/paper/2104.11186/) (2021)
- [On the Theory of Reinforcement Learning with Once-per-Episode Feedback](https://mlsanity.com/paper/2105.14363/) (2021)
- [Minimax Regret for Stochastic Shortest Path](https://mlsanity.com/paper/2103.13056/) (2021)
- [Online Apprenticeship Learning](https://mlsanity.com/paper/2102.06924/) (2021)
- [Implicit Finite-Horizon Approximation and Efficient Optimal Algorithms for Stochastic Shortest Path](https://mlsanity.com/paper/2106.08377/) (2021)
- [Differentially Private Regret Minimization in Episodic Markov Decision Processes](https://mlsanity.com/paper/2112.10599/) (2021)
- [Truly No-Regret Learning in Constrained MDPs](https://mlsanity.com/paper/2402.15776/) (2024)
- [Reinforcement Learning in Reward-Mixing MDPs](https://mlsanity.com/paper/2110.03743/) (2021)
- [Dynamic Model Predictive Shielding for Provably Safe Reinforcement Learning](https://mlsanity.com/paper/2405.13863/) (2024)
- [Optimal Uniform OPE and Model-based Offline Reinforcement Learning in Time-Homogeneous, Reward-Free and Task-Agnostic Settings](https://mlsanity.com/paper/2105.06029/) (2021)
- [When to Update Your Model: Constrained Model-based Reinforcement Learning](https://mlsanity.com/paper/2210.08349/) (2022)
- [Confidence-Budget Matching for Sequential Budgeted Learning](https://mlsanity.com/paper/2102.03400/) (2021)
- [Adaptive Discretization in Online Reinforcement Learning](https://mlsanity.com/paper/2110.15843/) (2021)
- [Optimistic Posterior Sampling for Reinforcement Learning with Few Samples and Tight Guarantees](https://mlsanity.com/paper/2209.14414/) (2022)
- [Provably Efficient Fictitious Play Policy Optimization for Zero-Sum Markov Games with Structured Transitions](https://mlsanity.com/paper/2207.12463/) (2022)
- [Achieving Fairness in Multi-Agent Markov Decision Processes Using Reinforcement Learning](https://mlsanity.com/paper/2306.00324/) (2023)
- [Cancellation-Free Regret Bounds for Lagrangian Approaches in Constrained Markov Decision Processes](https://mlsanity.com/paper/2306.07001/) (2023)
- [The Value of Reward Lookahead in Reinforcement Learning](https://mlsanity.com/paper/2403.11637/) (2024)
- [Reinforcement Learning with a Terminator](https://mlsanity.com/paper/2205.15376/) (2022)
- [UVIP: Model-Free Approach to Evaluate Reinforcement Learning Algorithms](https://mlsanity.com/paper/2105.02135/) (2021)
- [Near-Optimal Reinforcement Learning with Shuffle Differential Privacy](https://mlsanity.com/paper/2411.11647/) (2024)
- [A Bit of Freedom Goes a Long Way: Classical and Quantum Algorithms for Reinforcement Learning under a Generative Model](https://mlsanity.com/paper/2507.22854/) (2025)

## Abstract (arXiv)

State-of-the-art efficient model-based Reinforcement Learning (RL) algorithms typically act by iteratively solving empirical models, i.e., by performing full-planning on Markov Decision Processes (MDPs) built by the gathered experience. In this paper, we focus on model-based RL in the finite-state finite-horizon MDP setting and establish that exploring with greedy policies -- act by 1-step planning -- can achieve tight minimax performance in terms of regret, tildeO(√HSAT). Thus, full-planning in model-based RL can be avoided altogether without any performance degradation, and, by doing so, the computational complexity decreases by a factor of S. The results are based on a novel analysis of real-time dynamic programming, then extended to model-based RL. Specifically, we generalize existing algorithms that perform full-planning to such that act by 1-step planning. For these generalizations, we prove regret bounds with the same rate as their full-planning counterparts.
