Identification and off-policy learning of multiple objectives using adaptive clustering

• Published in: Neurocomputing (Amsterdam) 2017-11, Vol.263, p.39-47
• Main Authors: Karimpanal, Thommen George, Wilhelm, Erik
• Format: Article
• Language: English
• Subjects: Adaptive clustering; Multiobjective learning; Off-policy; Q-learning; Reinforcement learning
• ISSN: 0925-2312; 1872-8286
• DOI: 10.1016/j.neucom.2017.04.074

In this work, we present a methodology that enables an agent to make efficient use of its exploratory actions by autonomously identifying possible objectives in its environment and learning them in parallel. The identification of objectives is achieved using an online and unsupervised adaptive clustering algorithm. The identified objectives are learned (at least partially) in parallel using Q−learning. Using a simulated agent and environment, it is shown that the converged or partially converged value function weights resulting from off-policy learning can be used to accumulate knowledge about multiple objectives without any additional exploration. We claim that the proposed approach could be useful in scenarios where the objectives are initially unknown or in real world scenarios where exploration is typically a time and energy intensive process. The implications and possible extensions of this work are also briefly discussed.