A Pilot Evaluation of a Conversational Listener for Conversational User Interfaces

Current spoken conversational user interfaces (CUIs) are predominantly implemented using a sequential, utterance based, two-party, speak-wait/speak-wait approach. Human-human conversation 1) is not sequential, with overlap, interruption and back channels; 2) processes utterances before they are complete and 3) are often multi-party. As part of Honda Research Institute's Haru project a light weight word spotting speech recognition system - A conversational listener - was implemented to allow very fast turn-taking in simple voice interaction conditions. In this paper, we present a pilot evaluation of the conversational listener in a script follower context (which allows a robot to act out a dialog with a user). We compare a disembodied version of the system with expressive synthesis to Alexa with and without fast turn-taking. Qualitative results indicate that users were sensitive to turn-taking delay and characterful speech synthesis.