ABSTRACT
In this chapter, I describe the methodology used in the acoustic case study presented in Chapter 5, which was designed to test the hypothesis that the Guttural OCP in Ju∣'hoansi (described in Section 3.5.1) has its basis in the phonetic similarity of guttural consonants and vowels and in the temporal overlap of the acoustic cues associated with guttural consonants and guttural vowels. The dimension of aperiodicity is measured through both the Pitch Perturbation Quotient (PPQ) measure of time-domain aperiodicity (jitter) (Davis, 1976) and through the frequency-based measure of aperiodicity of the gamnitude of the first rahmonic peak (deKrom, 1993, 1995; Hillenbrand, Cleveland and Erickson, 1994; Qi and Hillman, 1997). The dimension of spectral slope is measured via the difference between the amplitude of the first and second harmonics (H1-H2).
