Title
TBQ(σ): Improving Efficiency of Trace Utilization for Off-Policy Reinforcement Learning.
Abstract
Off-policy reinforcement learning with eligibility traces faces is challenging because of the discrepancy between target policy and behavior policy. One common approach is to measure the difference between two policies in a probabilistic way, such as importance sampling and tree-backup. However, existing off-policy learning methods based on probabilistic policy measurement are inefficient when utilizing traces under a greedy target policy, which is ineffective for control problems. The traces are cut immediately when a non-greedy action is taken, which may lose the advantage of eligibility traces and slow down the learning process. Alternatively, some non-probabilistic measurement methods such as General Q($łambda$) and Naive Q($łambda$) never cut traces, but face convergence problems in practice. To address the above issues, this paper introduces a new method named TBQ(σ), which effectively unifies the tree-backup algorithm and Naive Q($łambda$). By introducing a new parameter σ to illustrate the degree of utilizing traces, TBQ(σ) creates an effective integration of TB($łambda$) and Naive Q($łambda$) and continuous role shift between them. The contraction property of TB(σ) is theoretically analyzed for both policy evaluation and control settings. We also derive the online version of TBQ(σ) and give the convergence proof. We empirically show that, for ε\in(0,1]$ in ε-greedy policies, there exists some degree of utilizing traces for $łambda\in[0,1]$, which can improve the efficiency in trace utilization for off-policy reinforcement learning, to both accelerate the learning process and improve the performance.
Year
DOI
Venue
2019
10.5555/3306127.3331799
adaptive agents and multi-agents systems
Field
DocType
Volume
Convergence (routing),Mathematical optimization,Importance sampling,Existential quantification,Computer science,Artificial intelligence,Probabilistic logic,Deep learning,Machine learning,Reinforcement learning
Journal
abs/1905.07237
Citations 
PageRank 
References 
0
0.34
0
Authors
5
Name
Order
Citations
PageRank
Longxiang Shi100.34
Shijian Li2115569.34
Longbing Cao32212185.04
Long Yang422.08
Gang Pan501.35