Assessment of a measure of response confidence for a speech recognition task in noise.

Abstract

ASSESSMENT OF A MEASURE OF RESPONSE CONFIDENCE FOR A SPEECH RECOGNITION TASK IN NOISE

JOHN ANDREW DUNDAS

Dissertation under the direction of Gary P Jacobson, Ph.D.

The development of a measure of response confidence for a speech understanding task is presented in this dissertation. Normal hearing participants completed speech understanding tasks in background noise and rated confidence in their responses. In experiment 1, the relationships between measured performance, perceived performance and confidence in the correctness of responses were investigated. In experiment 2, the effect of sentence context on response confidence was investigated. The main findings of this study are; 1. Confidence ratings of speech intelligibility performance can be consistently measured using simple tools, 2. Confidence ratings are strongly correlated with measured performance, 3. Confidence ratings are highly repeatable, 4. Sentence based test materials with a high degree of context result in the most accurate calibration to measured performance, and, 5. Low context sentences result in a faster growth of confidence (i.e., overconfidence). These findings suggest that confidence ratings could be a useful outcome measure in the evaluation of treatment efficacy in the hearing impaired population.