The Effect of Naturalness of Voice and Empathic Responses on Enjoyment, Attitudes and Motivation for Interacting with a Voice User Interface

Abstract

In human-computer interaction much attention is given to the development of natural and intuitive Voice User Interfaces (VUI). However, previous research has shown that humanlike systems will not necessarily be perceived positive by users. The study reported here examined the effect of human likeness on users’ rating of enjoyment, attitudes and motivation to use VUI in a Wizard-of-Oz experiment. Two attributes of human likeness, voice of the system (humanlike vs. machinelike) and social behavior of the system (expressing empathy vs. neutral) were manipulated. Regression analyses confirmed that perceived empathy of the VUI improved interaction enjoyment, attitude towards the system, and intrinsic motivation but no effect of voice was found. Session order also affected participants’ evaluation. In the second session, participants rated the VUI as more negative than in the first session. The results indicate that a VUI that expresses social behavior (e.g. showing empathy) is perceived as more favorable by the user. Furthermore, changing user expectations pose a challenge for the design of the VUI. The dynamics of user interactions must be taken into account when designing the VUI.