Syntactic complexity revisited: sensitivity of China's AES-generated scores to syntactic measures, effects of discourse-mode and topic.

This study aims to explore to what extent syntactic complexity predicts holistic scores generated by China's two prominent automated writing evaluation systems—pigai and iWrite, the results of which will have some implications for the validity of these two systems. In the meanwhile, this study targets how syntactic complexity differs across writing tasks—between- and within- discourse mode as well as the effects of topic on the use of syntactic measures. To these ends, we examined a corpus of 445 writing samples with 4 prompts on two discourse modes (argumentative and expository) written by Chinese freshmen. These samples were analyzed for the sensitivity of China's AES-generated scores to syntactic complexity, effects of topic and discourse-mode. Results indicated that there were no relationships between the variations of syntactic measures and the computer-generated scores. Strong topic effects were found within the same discourse mode, but no significant changes were observed in the use of syntactic measures across discourse modes. [ABSTRACT FROM AUTHOR]