Acoustic Properties of Formality in Conversational Japanese

This paper examines potential acoustic cues for level of formality in Japanese conversational speech using speech data gathered outside the laboratory, with the objective of using any significant cues to develop a model to predict level of formality in spoken Japanese. Based on previous work on the phonetic properties of formality in Japanese [1],[2] and other languages [3], and on a pilot study of informal geminate contractions in Japanese (section 2), the study examined the mean f0, articulation rate, and f0 range (the difference between the minimum and maximum f0 in an utterance) via direct examination of the data and a functional data analysis [4],[5]. Analysis of the speech data shows significant relationships between all three variables and level of formality, and a binary logistic regression indicates that the variables have some potential as predictors of formality independent of lexical cues, although further refinement of any model will be necessary.