Quantum mechanics

User interface

World Wide Web

Usability

Scale (ratio)

Ecology

Biology

Usability engineering

Web usability

Heuristic evaluation

Operating system

Usability inspection

Amazon rainforest

Computer science

Voice command device

Physics

Cognitive walkthrough

System usability scale

Artificial intelligence

Usability lab

Human–computer interaction

Speech recognition

SN Computer Science

Currently, the use of voice-assistants has been on the rise, but a user-centric usability evaluation of these devices is a must for ensuring their success. System Usability Scale (SUS) is one such popular usability instrument in a Graphical User Interface (GUI) scenario. However, there are certain fundamental differences between GUI and voice-based systems, which makes it uncertain regarding the suitability of SUS in a voice scenario. The present work has a twofold objective: to check the suitability of SUS for usability evaluation of voice-assistants and developing a subjective scale in line with SUS that considers the unique aspects of voice-based communication. We call this scale as the Voice Usability Scale (VUS). For fulfilling the objectives, a subjective test is conducted with 62 participants. An Exploratory Factor Analysis suggests that SUS has a number of drawbacks for measuring the voice usability. Moreover, in case of VUS, the most optimal factor structure identifies three main components: usability, affective, and recognizability and visibility. The current findings should provide an initial starting point to form a useful theoretical and practical basis for subjective usability assessment of voice-based systems.

Usability Evaluation of Artificial Intelligence-Based Voice Assistants: The Case of Amazon Alexa