Subjective ratings of sentences in clear versus conversational speech.

Abstract

Investigations of the relationship between speech acoustics and intelligibility face a significant methodological challenge, especially when using materials produced by multiple talkers and/or in multiple speaking styles. Ideally, acoustic analyses comparing talkers or styles will use identical materials for each. In contrast, intelligibility studies using meaningful stimuli must use either different materials or different listener groups to avoid learning effects. The latter solution becomes prohibitive when the number of talkers is large, such as in the Ferguson clear speech database (2004). While talkers recorded different materials in each speaking style, materials were the same for all talkers. For word intelligibility, familiarization prior to testing can prevent learning effects. For sentences, however, different listeners would be needed for each talker, resulting in 41 listener groups. An alternative solution is to use subjective rather than objective measures. This project explored the feasibili...