In this study, speech samples elicited by native and nonnative learners of Japanese on the argumentative monologue tasks were analyzed in terms of complexity, accuracy, fluency, and functional adequacy. The results showed the complexity was the most significant factor that separated different proficiency group.
The number of international students in Japan increased from 140,000 to 270,000 in the past ten years. However, none of the large-scale tests used for college admission purposes include speaking component, and an emphasis is placed on either reading (Noguchi et al., 2008) or listening (Kadokura, 2005). This has created a problem of admitting a large number of students with a gap between reading/listening and speaking proficiency. In order to solve this problem, the current project aims at (1) developing a corpus of argumentative and expository speech data by native (NS) and nonnative (NNS) speakers of Japanese, (2) identifying features of good academic speaking in Japanese, and (3) developing an online task-based assessment of academic speaking in Japanese. The corpus data consisted of speech samples by seventy NS and eighty NNS. All were college students, and the proficiency level of NNS differed from A2 to C1 in terms of CEFL (Council of Europe, 2001). There were thirty argumentative questions. Each participant talked about ten topics (six argumentative and four expository topics) which were randomly presented on the computer screen. The participants' speaking proficiency was rated and their speech samples were analyzed in terms of complexity, accuracy, fluency (CAF), and functional adequacy (FA) (Kuiken & Vedder, 2018). The results indicated that NS an NNS differed in all of the CAFFA measures, and complexity was the most significant factor that separated NS and NNS. Also, advanced NNS' speech was more coherent, complex and accurate than that of intermediate NNS. A qualitative analysis showed that NNS were unable to use conjunctive particles and deletion effectively to control the topic shift compared to NS, and advanced NNS were able to use conjunction and complex sentences to maintain cohesiveness than intermediate NNS.
