Using reinforcement learning to create communication channel management strategies for diverse users

Spoken dialogue systems typically do not manage the communication channel, instead using fixed values for such features as the amplitude and speaking rate. Yet, the quality of a dialogue can be compromised if the user has difficulty understanding the system. In this proof-of-concept research, we explore using reinforcement learning (RL) to create policies that manage the communication channel to meet the needs of diverse users. Towards this end, we first formalize a preliminary communication channel model, in which users provide explicit feedback regarding issues with the communication channel, and the system implicitly alters its amplitude to accommodate the user's optimal volume. Second, we explore whether RL is an appropriate tool for creating communication channel management strategies, comparing two different hand-crafted policies to policies trained using both a dialogue-length and a novel annoyance cost. The learned policies performed better than hand-crafted policies, with those trained using the annoyance cost learning an equitable tradeoff between users with differing needs and also learning to balance finding a user's optimal amplitude against dialoguelength. These results suggest that RL can be used to create effective communication channel management policies for diverse users.