  ChatGPT is a publicly available chatbot that can quickly generate texts on
given topics, but it is unknown whether the chatbot is really superior to human
writers in all aspects of writing and whether its writing quality can be
prominently improved on the basis of updating commands. Consequently, this
study compared the writing performance on a narrative topic by ChatGPT and
Chinese intermediate English (CIE) learners so as to reveal the chatbot's
advantage and disadvantage in writing. The data were analyzed in terms of five
discourse components using Coh-Metrix (a special instrument for analyzing
language discourses), and the results revealed that ChatGPT performed better
than human writers in narrativity, word concreteness, and referential cohesion,
but worse in syntactic simplicity and deep cohesion in its initial version.
After more revision commands were updated, while the resulting version was
facilitated in syntactic simplicity, yet it is still lagged far behind CIE
learners' writing in deep cohesion. In addition, the correlation analysis of
the discourse components suggests that narrativity was correlated with
referential cohesion in both ChatGPT and human writers, but the correlations
varied within each group.
