Effects of non modal voicing on the statistical description of fundamental frequency samples

• Grant number: 16/16544-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2016
• End date: October 31, 2017
• Field of knowledge: Linguistics, Literature and Arts - Linguistics - Linguistic Theory and Analysis
• Principal Investigator: Pablo Arantes
• Grantee: Isabela de Jesus Silveira
• Host Institution: Centro de Educação e Ciências Humanas (CECH). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The project's goal is to test the effect of non modal voicing on a methodology developed to determine the minimum sample length necessary to provide stable estimates of three statistical estimators of central tendency from an F0 contour. In the corpus used to test the methodology, which was comprised of speech samples of six languages, almost 80% of the speakers present some amount of non modal voicing. Some speakers make extensive use of non modal voicing, with almost 30% of f0 values below the modal register. The massive presence of vey low F0 values increases the variability of the samples introducing biases both in the estimators' values and stabilization time. To achieve the intended goal it will be necessary to develop a procedure that identifies the threshold between modal and non modal voicing with the least possible degree of subjectivity. We are also going to investigate the speaker-specificity of statistical measures of the F0 distributions such as standard deviation, skewness and kurtosis. Also, we are going to look for regularities among the speakers with respect to the linguistic context where non modal voicing occurs. A preliminary study suggests that stress degree is a good predictor of non modal voicing usage while prosodic boundaries are not.