Self-Organizing Maps for Storage and Transfer of Knowledge in Reinforcement Learning
This work addresses sample efficiency for reinforcement learning agents in continual learning scenarios, though it appears incremental as it builds on existing self-organizing map methods.
The paper tackles the problem of sample inefficiency in reinforcement learning by reusing knowledge from previously learned tasks to guide exploration in new tasks, using a variant of the growing self-organizing map algorithm. It demonstrates empirical validation in a simulated navigation environment and on a mobile micro-robotics platform, showing scalability and efficient storage of task knowledge.
The idea of reusing or transferring information from previously learned tasks (source tasks) for the learning of new tasks (target tasks) has the potential to significantly improve the sample efficiency of a reinforcement learning agent. In this work, we describe a novel approach for reusing previously acquired knowledge by using it to guide the exploration of an agent while it learns new tasks. In order to do so, we employ a variant of the growing self-organizing map algorithm, which is trained using a measure of similarity that is defined directly in the space of the vectorized representations of the value functions. In addition to enabling transfer across tasks, the resulting map is simultaneously used to enable the efficient storage of previously acquired task knowledge in an adaptive and scalable manner. We empirically validate our approach in a simulated navigation environment, and also demonstrate its utility through simple experiments using a mobile micro-robotics platform. In addition, we demonstrate the scalability of this approach, and analytically examine its relation to the proposed network growth mechanism. Further, we briefly discuss some of the possible improvements and extensions to this approach, as well as its relevance to real world scenarios in the context of continual learning.