|
KMID : 1022420150070020149
|
|
Phonetics and Speech Sciences
2015 Volume.7 No. 2 p.149 ~ p.156
|
|
|
Fluency Scoring of English Speaking Tests for Nonnative Speakers Using a Native English Phone Recognizer
|
|
Jang Byeong-Yong
Kwon Oh-Wook
|
|
|
Abstract
|
|
|
|
We propose a new method for automatic fluency scoring of English speaking tests spoken by nonnative speakers in a free-talking style. The proposed method is different from the previous methods in that it does not require the transcribed texts for spoken utterances. At first, an input utterance is segmented into a phone sequence by using a phone recognizer trained by using native speech databases. For each utterance, a feature vector with 6 features is extracted by processing the segmentation results of the phone recognizer. Then, fluency score is computed by applying support vector regression (SVR) to the feature vector. The parameters of SVR are learned by using the rater scores for the utterances. In computer experiments with 3 tests taken by 48 Korean adults, we show that speech rate, phonation time ratio, and smoothed unfilled pause rate are best for fluency scoring. The correlation of between the rater score and the SVR score is shown to be 0.84, which is higher than the correlation of 0.78 among raters. Although the correlation is slightly lower than the correlation of 0.90 when the transcribed texts are given, it implies that the proposed method can be used as a preprocessing tool for fluency evaluation of speaking tests.
|
|
|
KEYWORD
|
|
|
speaking fluency, support vector regression
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|