Beyond Differences: Assessing Effects of Shared Linguistic Features on L2 Writing Quality of Two Genres

This study explored the relationship between linguistic features and the rated quality of letters of application (LAs) and argumentative essays (AEs) composed in English by Chinese college-level English as a foreign language (EFL) learners. A corpus of 260 LAs and 260 AEs were analyzed via a confirmatory factor analysis. Latent variables were EFL writing quality, captured by writing scores, and lexical sophistication, syntactic complexity, and cohesion, each captured by different linguistic features in the two genres of writing. Results indicated that lexical decision times, moving average type-token ratio with a 50-word window, and complex nominals per clause explained 55.5 per cent of the variance in the holistic scores of both genres of writing. This pattern of predictivity was further validated with a test corpus of 110 LAs and 110 AEs, revealing that, albeit differing in genre, higher-rated LAs and AEs were likely to contain more sophisticated words and complex nominals and exhibit a higher type-token ratio with a 50-word window. These findings help enrich our understanding of the shared features of different genres of EFL writing and have potentially useful implications for EFL writing pedagogy and assessment.