title: Occurrence Frequencies of Acoustic Patterns of Vocal Fry in American English Speakers.
abstract: OBJECTIVE
  The goal of this study was to analyze the occurrence frequencies of three individual acoustic patterns (A, B, C) and of vocal fry overall (A + B + C) as a function of gender, word position in the sentence (Not Last Word vs. Last Word), and sentence length (number of words in a sentence).
  
  
  METHODS
  This is an experimental design.
  
  
  METHODS
  Twenty-five male and 29 female American English (AE) speakers read the Grandfather Passage. The recordings were processed by a Matlab toolbox designed for the analysis and detection of creaky segments, automatically identified using the Kane-Drugman algorithm. The experiment produced subsamples of outcomes, three that reflect a single, discrete acoustic pattern (A, B, or C) and the fourth that reflects the occurrence frequency counts of Vocal Fry Overall without regard to any specific pattern. Zero-truncated Poisson regression analyses were conducted with Gender and Word Position as predictors and Sentence Length as a covariate.
  
  
  RESULTS
  The results of the present study showed that the occurrence frequencies of the three acoustic patterns and vocal fry overall (A + B + C) are greatest at the end of sentences but are unaffected by sentence length. The findings also reveal that AE female speakers exhibit Pattern C significantly more frequently than Pattern B, and the converse holds for AE male speakers.
  
  
  CONCLUSIONS
  Future studies are needed to confirm such outcomes, assess the perceptual salience of these acoustic patterns, and determine the physiological correlates of these acoustic patterns. The findings have implications for the design of new excitation models of vocal fry.
authors.affiliation: Department of Communication Sciences and Disorders, Post Campus at Long Island University, 720 Northern Boulevard, Brookville, New York 11548. Electronic address: nassima.abdelli-beruh@liu.edu.
authors.forename: Nassima B
authors.initials: NB
authors.lastname: Abdelli-Beruh
authors.affiliation: Faculté Polytechnique de Mons, TCTS Lab at University of Mons, Boulevard Dolez, 31, B-7000 Mons, Belgium.
authors.forename: Thomas
authors.initials: T
authors.lastname: Drugman
authors.affiliation: Department of Educational Leadership and Administration, and Doctoral Program in Interdisciplinary Studies, Post Campus at Long Island University, 720 Northern Boulevard, Brookville, New York 11548.
authors.forename: R H
authors.initials: RH
authors.lastname: Red Owl
mesh_terms: D000162:Acoustics; D000293:Adolescent; D000328:Adult; D000465:Algorithms; D005260:Female; D006801:Humans; D008297:Male; D010363:Pattern Recognition, Automated; D010699:Phonation; D010700:Phonetics; D012737:Sex Factors; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography; D013061:Speech Acoustics; D013068:Speech Production Measurement / Q000379:methods*; D013997:Time Factors; D014833:Voice Quality; D055815:Young Adult
keywords: AE speakers; Acoustic patterns; Automated detection of vocal fry; Gender differences; Vocal fry