Noun phrasal complexity in ESL written essays under a constructed-response task: Examining proficiency and topic effects

This corpus-based study examined the effects of proficiency and topic on noun phrasal complexity in argumentative essays in a constructed-response task written by English as a second language users. Noun modifiers in 64 essays were counted as they fit 16 types of grammatical structure at several developmental stages of phrasal complexity. The study goes beyond most previous work on noun phrasal complexity in writing by investigating the use of noun modifiers in a constructed response task where the topic can have a possible influence. Results revealed that the group with lowest proficiency used fewer noun modifiers than higher proficiency groups at all stages of phrasal complexity. Our findings also revealed that essays from a more cognitively demanding topic employed more post-modifiers than pre-modifiers, and more noun modifiers from higher stages. Furthermore, noun modifiers from lower stages were more prone to topic effects, which means that their use depends substantially on the topic requirements. The results suggest that a fine-grained analysis of noun phrasal complexity can discriminate second language writers of different proficiencies (especially at the intermediate level), and essay topic can affect noun phrase complexity.