Analysis of the non-native English pronunciation based on structural representation of speech

Recently, a novel acoustic representation of speech was proposed, where dimensions of the non-linguistic factors can hardly be seen. Using this structural representation, individual learners were described as distorted phonemic structures and automatic evaluation of the pronunciation was investigated. This paper describes two new analyses using the proposed method. The first analysis is done to examine whether the method can trace the development of a student’s pronunciation appropriately using only a limited amount of speech. The second one focuses on the prosodic aspect of the pronunciation, especially stressed and unstressed vowels. The former indicates that the proposed method can show history of the student’s development adequately and the latter clarifies that size of the pronunciation structure is highly correlated with the pronunciation proficiency.