Audio signals in speech interfaces
Stefanie Shriver, Alan W. Black, Ronald Rosenfeld · 2000
This paper discusses a variety of types of non-lexical signals such as beeps, prosodic variation and speaker style changes, and we consider four cases in which such signals might be used to good effect. We discuss the results of user tests to determine if specific types of non-lexical signals are better in some situations than in others, and we discuss the advantages and disadvantages of using such signals. 1. INTRODUCTION This paper discusses options for including non-lexical cues in audio output in order to convey pertinent information to users of speech interface systems. By non-lexical cues we mean any noises or supra-lexical features such as prosody or pitch which can be inserted or altered in an otherwise lexical string. These non-lexical cues can be arbitrary (e.g. a beep to suggest that an item is optional) or non-arbitrary (e.g. a ticking clock sound to indicate that the item in question is a time value). We believe that non-lexical cues can be particularly useful for applic...