How complex is professional academic writing? A corpus-based analysis of research articles in 'hard' and 'soft' disciplines

This study focuses on the analysis of linguistic complexity in professional academic writing in light of the empirical evidence provided by a 1,597,000-word corpus of ‘hard’ (life and physical sciences) and ‘soft’ (arts and social) scientific research articles published in leading peer-review journals. Specifically, this investigation aims both to describe the complexity features of texts written by professional authors and to test the hypothesis that linguistic complexity varies across disciplines. Since previous studies have revealed that automatic complexity indices do not sufficiently succeed in providing a comprehensive description of complexity of texts, in this paper complexity has been measured in two ways: quantitatively through the indexes provided by Lu’s (2010) L2 Syntactic Complexity Analyser, and through the more qualitative analysis of a selection of metrics associated with clausal and phrasal complexity in seminal studies. The data show, first, that syntactic complexity indices (basically, strategies of coordination and subordination) are statistically relevant to the characterisation of specifically the soft-science disciplines; second, that there is a continuum across subdisciplines within the broad distinction of soft versus hard genres; and, third, that the soft genre demonstrates a more stable productivity of clausal-complexity strategies, while phrasal-complexity features are more pervasive in the hard-science subcorpus.