Automatically assessing the oral proficiency of proficient L2 speakers

We consider the automatic assessment of oral proficiency for advanced second language speakers. A spoken dialogue system is used to guide students through a reading and a repeating exercise and to record their responses. Automatically-derived indicators of proficiency that have proved successful in other studies are calculated from their speech and compared with human ratings of the same data. It is found that, in contrast to the findings of other researchers, posterior scores correlate poorly with human assessments of the reading exercise. Furthermore, the repeating exercise is found both to be more challenging and to provide a better means of automatic assessment than the reading exercise for our test population.