Describing Voice Period Variability by Means of Time Series Structural Analysis

GABRIEL ALEJANDRO ALZAMENDI; GASTÓN SCHLOTTHAUER

Florencia

Workshop; MAVEBA 2017; 2017

Universitá degli Studi di Firenze

Variability in voice fundamental period is considered as an important indicator describing voice phonation and vocal condition. Acoustical parameters based on perturbation analysis are commonly applied for assessing period variability. Even though perturbation analysis is widely accepted, it is not able to describe in detail the various normally observed phenomena. In this work, period variability is described by means of state space structural analysis, which allows for optimal estimating and  computing three components in the period sequence, namely trend, cycle and perturbation. Structural analysis is applied for decomposing period  sequences obtained from type 1 sustained vowels, corresponding to both healthy and pathological subjects. Then, the estimated components are independently processed in order to reveal the most relevant information. It is shown that structural analysis suitable describes period variability,  where the most important aspects are modeled in the structural  components: trend, cycle and perturbation. Results suggest that  structural analysis performs well on healthy and pathological cases, and that period variability is explained by cycle and perturbation components.