Ratings of voicing disruptions
T. Dean Clack, R. E. Stone · The Journal of the Acoustical Society of America · 1979
Perceptual judgments of speech are used by clinicians, by those assessing telecommunication systems, etc.—often without systematic evaluations of reliability or accuracy. To examine such issues, brief disruptions in voicing are studied in samples of flowing speech, i.e., via recordings of a woman reading two sentences in examples of her “worst” to “best” possible voice during and after recovery from laryngitis. Five samples were heard (real time) twice by 11 listeners who graphically rated each for disruption severity along a normal-to-abnormal continuum. These ratings reveal large and significant disparities in some rejudgments of identical samples. and thus suggest the operation of sequential dependencies. A simple “linear-with-memory” model is developed to describe such operations. In a follow-up study, judgments were obtained again using graphic-rating protocols incorporating descriptive guides. This effectively reapportions the ratings, and the sequential dependencies are even more evident. The model demonstrates utility in describing and recursively predicting these ratings by individuals as well as groups of listeners. [Work supported by NIH and Department of Otorhinolaryngology, University of Michigan Medical School.]