Speech Graffiti vs. Natural Language: Assessing the User Experience

Speech-based interfaces have great potential but are hampered by problems related to spoken language such as variability, noise and ambiguity. Speech Graffiti was designed to address these issues via a structured, universal interface protocol for interacting with simple machines. Since Speech Graffiti requires that users speak to the system in a certain way, we were interested in how users might respond to such a system when compared with a natural language system. We conducted a user study and found that 74% of users preferred the Speech Graffiti system to a natural language interface in the same domain. User satisfaction scores were higher for Speech Graffiti and task completion rates were roughly equal.