# Efficiently Escaping Saddle Points for Policy Optimization

arXiv: https://arxiv.org/abs/2311.08914 · HTML: https://mlsanity.com/paper/2311.08914/

## Key facts

- Cited by 1 papers in the map (data through 14 Oct 2026).
- Builds on 20 of its 38 references that are in the map.
- First posted on arXiv 15 Nov 2023.

## Builds on (most cited first, 20 of 20)

- [Proximal Policy Optimization Algorithms](https://mlsanity.com/paper/1707.06347/) (2017)
- [Trust Region Policy Optimization](https://mlsanity.com/paper/1502.05477/) (2015)
- [High-Dimensional Continuous Control Using Generalized Advantage Estimation](https://mlsanity.com/paper/1506.02438/) (2015)
- [Deep Reinforcement Learning that Matters](https://mlsanity.com/paper/1709.06560/) (2017)
- [SAGA: A Fast Incremental Gradient Method With Support for Non-Strongly Convex Composite Objectives](https://mlsanity.com/paper/1407.0202/) (2014)
- [Safe, Multi-Agent, Reinforcement Learning for Autonomous Driving](https://mlsanity.com/paper/1610.03295/) (2016)
- [SARAH: A Novel Method for Machine Learning Problems Using Stochastic Recursive Gradient](https://mlsanity.com/paper/1703.00102/) (2017)
- [Stochastic Variance-Reduced Policy Gradient](https://mlsanity.com/paper/1806.05618/) (2018)
- [On the Convergence and Sample Efficiency of Variance-Reduced Policy Gradient Method](https://mlsanity.com/paper/2102.08607/) (2021)
- [Sample Efficient Policy Gradient Methods with Recursive Variance Reduction](https://mlsanity.com/paper/1909.08610/) (2019)
- [An Improved Convergence Analysis of Stochastic Variance-Reduced Policy Gradient](https://mlsanity.com/paper/1905.12615/) (2019)
- [Stochastic Cubic Regularization for Fast Nonconvex Optimization](https://mlsanity.com/paper/1711.02838/) (2017)
- [Momentum-Based Policy Gradient Methods](https://mlsanity.com/paper/2007.06680/) (2020)
- [Policy Optimization with Stochastic Mirror Descent](https://mlsanity.com/paper/1906.10462/) (2019)
- [A Hybrid Stochastic Policy Gradient Algorithm for Reinforcement Learning](https://mlsanity.com/paper/2003.00430/) (2020)
- [Sample Complexity of Policy Gradient Finding Second-Order Stationary Points](https://mlsanity.com/paper/2012.01491/) (2020)
- [Bregman Gradient Policy Optimization](https://mlsanity.com/paper/2106.12112/) (2021)
- [PAGE-PG: A Simple and Loopless Variance-Reduced Policy Gradient Method with Probabilistic Gradient Estimation](https://mlsanity.com/paper/2202.00308/) (2022)
- [Stochastic Recursive Variance-Reduced Cubic Regularization Methods](https://mlsanity.com/paper/1901.11518/) (2019)
- [A Cubic-regularized Policy Newton Algorithm for Reinforcement Learning](https://mlsanity.com/paper/2304.10951/) (2023)

## Built on by (most cited first, 1 of 1)

- [Bellman-Certified Rounding for Sparse Policy Deployment in MDPs](https://mlsanity.com/paper/2610.00325/) (2026)

## Abstract (arXiv)

Policy gradient (PG) is widely used in reinforcement learning due to its scalability and good performance. In recent years, several variance-reduced PG methods have been proposed with a theoretical guarantee of converging to an approximate first-order stationary point (FOSP) with the sample complexity of O(ε-3). However, FOSPs could be bad local optima or saddle points. Moreover, these algorithms often use importance sampling (IS) weights which could impair the statistical effectiveness of variance reduction. In this paper, we propose a variance-reduced second-order method that uses second-order information in the form of Hessian vector products (HVP) and converges to an approximate second-order stationary point (SOSP) with sample complexity of tildeO(ε-3). This rate improves the best-known sample complexity for achieving approximate SOSPs by a factor of O(ε-0.5). Moreover, the proposed variance reduction technique bypasses IS weights by using HVP terms. Our experimental results show that the proposed algorithm outperforms the state of the art and is more robust to changes in random seeds.
