# On the Global Optimality of Policy Gradient Methods in General Utility Reinforcement Learning

arXiv: https://arxiv.org/abs/2410.04108 · HTML: https://mlsanity.com/paper/2410.04108/

## Key facts

- Cited by 6 papers in the map (data through 14 Oct 2026).
- Placed in Offline RL algorithms, one of 13 directions in Offline RL and imitation learning from data.
- Builds on 29 of its 44 references that are in the map.
- First posted on arXiv 5 Oct 2024.

## Placed in

- Offline RL and imitation learning from data / [Offline RL algorithms](https://mlsanity.com/offlinerl/offline-rl-algorithms/)

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

- [Generative Adversarial Imitation Learning](https://mlsanity.com/paper/1606.03476/) (2016)
- [Diversity is All You Need: Learning Skills without a Reward Function](https://mlsanity.com/paper/1802.06070/) (2018)
- [Provably Efficient Reinforcement Learning with Linear Function Approximation](https://mlsanity.com/paper/1907.05388/) (2019)
- [On the Global Convergence Rates of Softmax Policy Gradient Methods](https://mlsanity.com/paper/2005.06392/) (2020)
- [Provably Efficient Maximum Entropy Exploration](https://mlsanity.com/paper/1812.02690/) (2018)
- [FLAMBE: Structural Complexity and Representation Learning of Low Rank MDPs](https://mlsanity.com/paper/2006.10814/) (2020)
- [Global Optimality Guarantees For Policy Gradient Methods](https://mlsanity.com/paper/1906.01786/) (2019)
- [On the Convergence Rates of Policy Gradient Methods](https://mlsanity.com/paper/2201.07443/) (2022)
- [Variational Policy Gradient Method for Reinforcement Learning with General Utilities](https://mlsanity.com/paper/2007.02151/) (2020)
- [Reward is enough for convex MDPs](https://mlsanity.com/paper/2106.00661/) (2021)
- [On the Convergence and Sample Efficiency of Variance-Reduced Policy Gradient Method](https://mlsanity.com/paper/2102.08607/) (2021)
- [Concave Utility Reinforcement Learning: the Mean-Field Game Viewpoint](https://mlsanity.com/paper/2106.03787/) (2021)
- [On Linear Convergence of Policy Gradient Methods for Finite MDPs](https://mlsanity.com/paper/2007.11120/) (2020)
- [Consistent On-Line Off-Policy Evaluation](https://mlsanity.com/paper/1702.07121/) (2017)
- [Linear Convergence of Natural Policy Gradient Methods with Log-Linear Policies](https://mlsanity.com/paper/2210.01400/) (2022)
- [The Importance of Non-Markovianity in Maximum State Entropy Exploration](https://mlsanity.com/paper/2202.03060/) (2022)
- [Cumulative Prospect Theory Meets Reinforcement Learning: Prediction and Control](https://mlsanity.com/paper/1506.02632/) (2015)
- [Challenging Common Assumptions in Convex Reinforcement Learning](https://mlsanity.com/paper/2202.01511/) (2022)
- [Submodular Reinforcement Learning](https://mlsanity.com/paper/2307.13372/) (2023)
- [Active Exploration via Experiment Design in Markov Chains](https://mlsanity.com/paper/2206.14332/) (2022)
- [Reinforcement Learning in Low-Rank MDPs with Density Features](https://mlsanity.com/paper/2302.02252/) (2023)
- [Reinforcement Learning with General Utilities: Simpler Variance Reduction and Large State-Action Space](https://mlsanity.com/paper/2306.01854/) (2023)
- [Elementary Analysis of Policy Gradient Methods](https://mlsanity.com/paper/2404.03372/) (2024)
- [Scalable Primal-Dual Actor-Critic Method for Safe Multi-Agent RL with General Utilities](https://mlsanity.com/paper/2305.17568/) (2023)
- [Global Reinforcement Learning: Beyond Linear and Convex Rewards via Submodular Semi-gradient Methods](https://mlsanity.com/paper/2407.09905/) (2024)
- [Joint Optimization of Multi-Objective Reinforcement Learning with Policy Gradient Based Algorithm](https://mlsanity.com/paper/2105.14125/) (2021)
- [Stochastic Optimization under Hidden Convexity](https://mlsanity.com/paper/2401.00108/) (2023)
- [Policy Gradient for Reinforcement Learning with General Utilities](https://mlsanity.com/paper/2210.00991/) (2022)
- [On the Convergence of Projected Policy Gradient for Any Constant Step Sizes](https://mlsanity.com/paper/2311.01104/) (2023)

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

- [Soft Forward-Backward Representations for Zero-shot Reinforcement Learning with General Utilities](https://mlsanity.com/paper/2602.06769/) (2026)
- [Breaking the Bias Barrier in Concave Multi-Objective Reinforcement Learning](https://mlsanity.com/paper/2603.08518/) (2026)
- [Robust Optimization for Mitigating Reward Hacking with Correlated Proxies](https://mlsanity.com/paper/2604.12086/) (2026)
- [Convex Markov Games and Beyond: New Proof of Existence, Characterization and Learning Algorithms for Nash Equilibria](https://mlsanity.com/paper/2602.12181/) (2026)
- [Robust General Utility for Reinforcement Learning](https://mlsanity.com/paper/2608.03562/) (2026)
- [Online Learning on Hidden-Convex Losses via Algorithmic Equivalence: Optimal Regret, Geometric Barrier, and Bandit Feedback](https://mlsanity.com/paper/2605.26373/) (2026)

## Abstract (arXiv)

Reinforcement learning with general utilities (RLGU) offers a unifying framework to capture several problems beyond standard expected returns, including imitation learning, pure exploration, and safe RL. Despite recent fundamental advances in the theoretical analysis of policy gradient (PG) methods for standard RL and recent efforts in RLGU, the understanding of these PG algorithms and their scope of application in RLGU still remain limited. In this work, we establish global optimality guarantees of PG methods for RLGU in which the objective is a general concave utility function of the state-action occupancy measure. In the tabular setting, we provide global optimality results using a new proof technique building on recent theoretical developments on the convergence of PG methods for standard RL using gradient domination. Our proof technique opens avenues for analyzing policy parameterizations beyond the direct policy parameterization for RLGU. In addition, we provide global optimality results for large state-action space settings beyond prior work which has mostly focused on the tabular setting. In this large scale setting, we adapt PG methods by approximating occupancy measures within a function approximation class using maximum likelihood estimation. Our sample complexity only scales with the dimension induced by our approximation class instead of the size of the state-action space.
