Hesitations in Spontaneous Speech: Acoustic Analysis and Detection

Spontaneous speech is different from any other type of speech in many ways, with speech disfluencies being the prominent feature. These phenomena both play an important role in communication, and also cause problems for automatic speech processing. In this study we present the results of acoustic analysis of the most frequent disfluencies voiced hesitations (filled pauses and lengthenings) across different speaking styles in spontaneous Russian speech, as well as results of experiments on their detection using SVM classifier on a joint Russian and English spontaneous speech corpus. Results of acoustic analysis showed significant differences in fundamental frequency and energy distribution ratios of hesitations and their contexts across speaking styles in Russian: comparing to the dialogues, in monologues speakers exhibit more prosodic cues for the adjacent context and hesitations. Experiments on detection of voiced hesitations on a mixed language and style corpus with SVM resulted in achieving F1-score = 0.48 (With F1-score = 0.55 for only Russian data).