Describing the development of intonational categories using a target-oriented parametric approach

In this paper we analyze the relation between adults’ intonational categories as described in the ToBI framework and children’s intonation contours, using a parametric approach and cluster evaluation methods. In the field of prosody, an increasing number of studies on the development of intonation apply the intonational categories of adult speech described as a sequence of high (H) and low (L) tones to child speech [1, 2]. However, the categories described by ToBI or by its languagespecific variants are developed for adult speakers. Instead of imposing adult category representations on the description of developmental stages in L1 intonation acquisition, we propose and validate a parametric approach and cluster evaluation methods [3, 4] that are applicable to both adult and child speech. First, we show that clusters of parametrized contours obtained from German adult-directed and child-directed speech correlate well with German ToBI categories. We then assess how well clusters at different stages of intonation acquisition correspond to adult target categories. Our results indicate that the proposed methodology is capable of demonstrating, in qualitative and quantitative terms, the continuous development of intonational categories at early ages towards adult target categories.