# Near-Optimal Goal-Oriented Reinforcement Learning in Non-Stationary Environments

@article{Chen2022NearOptimalGR, title={Near-Optimal Goal-Oriented Reinforcement Learning in Non-Stationary Environments}, author={Liyu Chen and Haipeng Luo}, journal={ArXiv}, year={2022}, volume={abs/2205.13044} }

We initiate the study of dynamic regret minimization for goal-oriented reinforcement learning modeled by a non-stationary stochastic shortest path problem with changing cost and transition functions. We start by establishing a lower bound Ω(( B ⋆ SAT ⋆ (∆ c + B 2 ⋆ ∆ P )) 1 / 3 K 2 / 3 ) , where B ⋆ is the maximum expected cost of the optimal policy of any episode starting from any state, T ⋆ is the maximum hitting time of the optimal policy of any episode starting from the initial state, SA is…

## 3 Citations

### Reaching Goals is Hard: Settling the Sample Complexity of the Stochastic Shortest Path

- Computer ScienceArXiv
- 2022

It is shown that there exists a worst-case SSP instance with S states, A actions, minimum cost c min, and maximum expected cost of the optimal policy over all states B ⋆, and it is proved that horizon-free regret is impossible in SSPs general an open system.

### A Unified Algorithm for Stochastic Path Problems

- Computer ScienceArXiv
- 2022

The first regret guarantees in this general problem are provided by analyzing a simple optimistic algorithm and the regret bound matches the best known results for the well-studied special case of stochastic shortest path (SSP) with all non-positive rewards.

### Nonstationary Reinforcement Learning with Linear Function Approximation

- Computer ScienceArXiv
- 2020

This work develops the first dynamic regret analysis in nonstationary reinforcement learning with function approximation in episodic Markov decision processes with linear function approximation under drifting environment and proposes a parameter-free algorithm that works without knowing the variation budgets but with a slightly worse dynamic regret bound.

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