Validation of Phonetic Transcriptions Based on Recognition Performance

In fundamental linguistic as well as in speech technology re search there is an increasing need for procedures to automat ically generate and validate phonetic transcriptions. Whereas much research has already focussed on the automatic genera tion o f phonetic transcriptions, far less attention has been paid to the validation of such transcriptions. In the little research performed in this area, the estimation o f the quality o f (auto matically generated) phonetic transcriptions is typically based on the comparison between these transcriptions and a human made reference transcription. We believe, however, that the quality o f phonetic transcriptions should ideally be estimated with the application in which the transcriptions will be used in mind, provided that the application is known at validation time. The application focussed on in this paper is automatic speech recognition, the validation criterion is the word error rate. We achieved a higher accuracy with a recogniser trained on an automatically generated transcription than with a similar recogniser trained on a human-made transcription resembling a human-made reference transcription more. This indicates that the traditional validation approach may not always be the most optimal one. 1