Lexical Richness and Syntactic Complexity as Predictors of Academic Writing Performance

Language researchers have long looked for ways to investigate the connection between textual language use and the development of both L1 and L2 writing. The purpose of this research study is to examine the predictors of writing quality in terms of lexical richness and syntactic complexity in academic writing. The study was based on a hypothesis that the lexical sophistication and the mean length T-unit (MLTU) are the indicators of writing quality.  A corpus of 50 article abstracts written by Tunisian scholars was analyzed and scored using a holistic scoring rubric that indicates writing quality (test of written English), and then regressed against the chosen measures of lexical richness and syntactic complexity. The findings revealed that lexical sophistication   GSL-1 1000 words is the indicator of writing quality. For syntactic complexity, findings showed that the mean length T-unit (MLTU) is not a good predictor of academic writing. However, the clause per T-unit (C/TU) indicated a strong correlation with writing quality. Furthermore, the ability to use sophisticated vocabulary rather than grammatical knowledge was an effective predictor of academic writing. The results of this research can help EFL scholars improve the quality of their writing so they can employ it in academic writing.