An acoustical and perceptual analysis of the vocal behavior of classroom teachers

This study examined perceptual evaluations of classroom teachers, acoustic measures of their voices ( fundamental frequency [F-0], frequency range [F0 SD], % jitter, and % shimmer), and behavioral measures (rate, dysfluencies, and episodes of vocal fry). This preliminary study attempted to identify p erceptual and acoustic measures that discriminate between effective and les s effective classroom teachers. Seven teachers were recorded on audiotape w hile presenting a 10-12 minute lecture. Voice samples (N > 200) for each te acher were subjected to acoustic analysis. Audiotapes were evaluated by lis teners (N = 180), who scale-rated and used an adjective checklist to determ ine teachers' overall effectiveness. A three-member team evaluated global a spects of voice (e.g., use of pauses, inflections, contours, and phrasing). Results indicated that frequency range, frequency variability, rate, and n umber of dysfluencies appeared to correlate with perceptual judgments of te aching effectiveness and specific adjective descriptors. F-0, % jitter, and % shimmer did not appear to be linked to perceptual judgments. Individual case profiles were established and recommendations were made for future emp irical research involving larger samples of teachers.