Using likelihood ratios to perform utterance verification in automatic pronunciation assessment
Febe de Wet, Catia Cucchiarini, Helmer Strik, Lou Boves · 1999
The aim of our current research is to investigate the possibility of using likelihood ratios to perform utterance verification within the context of automatic oral proficiency assessment. The likelihood ratios under investigation have the appealing feature that they may be computed simply by using an off-theshelf automatic speech recognition system in two different recognition modes (forced and free phone) instead of using a system with specifically trained anti-models. We achieved 93% correct classification for 10 phonetically rich sentences uttered by 60 non-native language students. 1. INTRODUCTION The long-term goal of our research is to employ ASR technology in an automatic pronunciation test for Dutch as a second language. As a consequence of this aim we are not concerned with learners of Dutch with a specific mother tongue, but rather with a group of speakers who are highly varied in this respect. In this sense our situation is different from that of many studies on the use of...