Should Speech Dialogue System Use Honorific Expression

As voice recognition technology develops, we talk to smart speakers and other voice assistants more and more frequently in everyday life. Many such speech dialog systems are designed to use honorifics. However, humans do not always use honorifics in everyday conversation. Thus, we consider that voice assistants need to use other forms of expression in addition to so-called polite language. In this study, we conducted a comparative experiment to investigate how the speaking styles of smart speakers affect human listeners. In this experiment, a participant talked to a smart speaker to make travel plans. We analyzed the results of questionnaires. We found that a smart speaker's friendly speaking style influenced the participants' impressions and thus shaped the development of good relationships between humans and agents. Our findings indicate that people regard agents as friends if they speak in a friendly manner.