Voice Usability Scale: Measuring the User Experience with Voice Assistants

Voice Assistants (VAs) have grown in popularity over recent years and forecasted for exceptional growth over the coming years. Yet many issues still exist which prevent their adoption. Therefore, the usability of VAs is the crucial area that recent research should focus on, keeping in mind their commercialization aspect. This study aims to construct a valid and reliable scale for subjective usability evaluation of voice assistants. The Voice Usability Scale (VUS) is formulated based on three themes: information quality and relevance, semantic intelligence, and user satisfaction, extracted from extant literatures. In this study, a subjective experiment is performed with 61 subjects across some popular commercially available (VAs) to check the scale's validity and reliability. The reliability and face validity of the scale is high (Cronbach's alpha: 0.807, Face validity index (FVI): 0.96). Usability practitioners can use this scale in subjective evaluations of VAs and research purposes.