Stability of Prosodic Characteristics Across Age and Gender Groups

The indexical function of speech prosody signals the membership of a speaker in a social group. The factors of age and gender are relatively easy to establish but their reflection in speech characteristics can be less straightforward as they interact with other social aspects. Therefore, diverse speaker communities should be investigated with the aim of their subsequent comparison. Our study provides data for the population of adult speakers of Czech – a West Slavic language of Central Europe. The sample consists of six age groups (20 to 80 years of age) with balanced representation of gender. The search for age and gender related attributes covered both global acoustic descriptors and linguistically informed prosodic feature extraction. Apart from commonly used measures and methods we also exploited Legendre polynomials, k-means clustering and a newly designed Cumulative Slope Index (CSI). The results specify general deceleration of articulation rate with age and lowering of F0 in aging Czech women, and reveal an increase in CSI of both F0 tracks and intensity curves with age. Furthermore, various melodic shapes were found to be distributed unequally across the age groups.