Comparing theory-based models of grammatical complexity in student writing

The present study tests the empirical adequacy of competing models of grammatical complexity in university student writing, based on analysis of disciplinary texts from L1-English and L2-English students. The results show that grammatical complexity in student writing must be treated as a multi-dimensional linguistic construct, distinguishing among both structural types and syntactic functions. We compare the results here to previous research (Biber et al., 2024a, b), showing a similar patterning of complexity features in student writing and the broader domain of general writing. Two of these groupings – dependent phrases functioning as noun modifers, and fnite dependent clauses functioning as clause-level constituents – are especially interesting. These two groupings represent the strongest co-occurrence patterns in general writing, but only the dependent clause grouping is represented in student writing. This discrepancy is interpreted relative to the development of advanced profciency in the use of complexity features by university students.