Learning Communication Policies for Different Follower Behaviors in a Collaborative Reference Game
This work addresses the challenge of modeling dynamic agent behaviors in multi-agent systems, though it is incremental as it builds on existing reinforcement learning methods.
The paper tackled the problem of training neural agents to adapt their communication strategies to different partner behaviors in a collaborative reference game, showing that adding a communicative effort penalty leads to less verbose and more adaptive strategies.
Albrecht and Stone (2018) state that modeling of changing behaviors remains an open problem "due to the essentially unconstrained nature of what other agents may do". In this work we evaluate the adaptability of neural artificial agents towards assumed partner behaviors in a collaborative reference game. In this game success is achieved when a knowledgeable Guide can verbally lead a Follower to the selection of a specific puzzle piece among several distractors. We frame this language grounding and coordination task as a reinforcement learning problem and measure to which extent a common reinforcement training algorithm (PPO) is able to produce neural agents (the Guides) that perform well with various heuristic Follower behaviors that vary along the dimensions of confidence and autonomy. We experiment with a learning signal that in addition to the goal condition also respects an assumed communicative effort. Our results indicate that this novel ingredient leads to communicative strategies that are less verbose (staying silent in some of the steps) and that with respect to that the Guide's strategies indeed adapt to the partner's level of confidence and autonomy.