Core Concepts
Optimizing exploration in reinforcement learning by incorporating offline data to improve coverage and efficiency.
Abstract
The content discusses the benefits of hybrid reinforcement learning, focusing on optimizing exploration by combining online and offline data. It introduces DISC-GOLF, a modified optimistic online algorithm, showcasing provable gains over online-only and offline-only approaches. Theoretical analysis and numerical simulations demonstrate improved exploration efficiency with the integration of offline datasets.
Abstract:
Hybrid RL combines online and offline data for improved exploration.
DISC-GOLF modifies an optimistic algorithm for enhanced regret bounds.
Theoretical results show benefits of integrating offline data in RL algorithms.
Introduction:
RL involves online and offline approaches; hybrid RL combines both.
Limited research on the benefits of hybrid RL despite recent interest.
Previous studies focus on coverage assumptions for offline datasets.
Problem Setup:
Consideration of function class F for modeling optimal Q-function.
Definitions related to MDPs, value functions, and Q-functions introduced.
Measures of Complexity:
Offline complexity measures based on concentrability concepts.
Online complexity measures like SEC extended for hybrid RL analysis.
Reduced Complexity Through State-Action Space Partition:
Partitioning state-action space reduces complexity in hybrid algorithms.
Partial all-policy concentrability is less stringent than single-policy concentrability.
Main Result:
Regret bound theorem established for DISC-GOLF algorithm.
Regret characterized by complexity measures over partitions Xoff and Xon.
Case Studies:
Tabular MDPs: Bounds on sample complexities in tabular settings demonstrated.
Linear MDPs: Analysis of linear MDPs showing reduced regret dependence on dimensionality.
Block MDPs: Application to block MDPs with latent state spaces discussed.
Conclusion and Discussion:
Discussion on practical implications, limitations, future work, and potential improvements in hybrid RL algorithms presented.
Stats
"Unlike these, we are able to include the entire offline dataset – we do not need to discard any offline samples."
"Reg(Non) = O inf Xon,Xoff s βH4Non N2on Noff coff(F, Xoff) + p βH4Noncon(F, Xon, Non)"
Quotes
"A well-designed online algorithm should “fill in the gaps” in the offline dataset."
"Our Contributions: We address this gap by modifying an optimistic algorithm for general function approximation."