Naive auditory identification and discrimination of similar voices by familiar listeners

Abstract

Experiments are described which investigate the ability of listeners to identify and distinguish between individuals with similar voices whom they know well. Subjects were tested on speech of varying duration from four familiar male speakers and two foils. Results in identification tasks range from chance for single words to almost perfect for longer utterances. Performance in discrimination is better than identification, but both show nevertheless an estimated 'judicially fatal error' rate of about 7 per cent and 5 per cent respectively. Correlation between subjects' accuracy and confidence in their judgements is demonstrated. Results indicate that some voices, and some tokens of the same utterance, may differ in their recognizability. Forensic implications are discussed.