Automatic evaluation of Dutch pronunciation by using speech recognition technology

The ultimate aim of the research reported on in this paper is to develop a system for automatic assessment of foreign speakers´ pronunciation of Dutch. The aim of the experiment was to determine whether pronunciation ratings assigned by human experts could be predicted on the basis of scores calculated by an automatic speech recognizer. To this end 20 native and 60 non-native speakers of Dutch read ten phonetically rich sentences over the telephone. The automatic speech recognizer was trained with read speech of 4019 Dutch subjects with varying regional accents. The results show that the human scores can be accurately predicted, even in the case of telephone speech. Analysis of the various types of human ratings and automatic measures provides more insight into the relationship between human and machine scores and indicates how the automatic measures can be further improved to achieve even greater predictive power