Voice quality: Not only about “you” but also about “your interlocutor”

This paper investigates the effect of voice quality in commutative speech. Voice quality is often considered as the characteristic auditory colouring of an individual speaker´s voice, but in our study, we find that voice quality can also reveal information about the interlocutor in everyday social interactions. In the correlation analysis between acoustic measures and interlocutors, the effect caused by the linguistic content was reduced by focusing on the corpus of the commonly-used Japanese word “yes”. The distributions of voice quality features, e.g., Normalized Amplitude Quotient (NAQ), jitter and shimmer, showed a clear difference among different interlocutors, e.g., friend or business partner. Automatic classification of interlocutors was conducted using random forest method with voice quality, prosodic and spectral features. The best classification accuracy was 76.9% over four interlocutors´ data.