‘Can I Trust the Spoken Dialogue System Because It Uses the Same Words as I Do?’—Influence of Lexically Aligned Spoken Dialogue Systems on Trustworthiness and User Satisfaction

Abstract

One of many ways in which spoken dialogue systems (SDS) are becoming more and more flexible is in their choice of words (e.g. alignment to the user’s vocabulary). We examined how users perceive such adaptive and non-adaptive SDS regarding trustworthiness and usability. In Experiment 1, 130 participants read out questions to an SDS that either made or did not make lexical alignment in its replies. They perceived higher cognitive demand when the SDS did not employ alignment. In Experiment 2, 135 participants listened to a conversation between a human and the same SDS in an online study. They judged the aligned SDS to have more integrity and to be more likeable. Implications for the design of SDS are discussed.