Corpus-based bundle analysis to disciplinary variations: Relocating the role of bundle extraction criteria

Previous lexical bundle research has stimulated heated discussions on disciplinary variations and disciplinary specificity-generality spectrum. The current study explores whether (and how) bundle extraction criteria (i.e. frequency, dispersion, and bundle length) may affect the conclusions on disciplinary variations and specificity-generality. Focusing on eight disciplines, it used an 11-million corpus of academic journal articles with a balanced design (the same number of texts and similar average text length for each subcorpus). The results indicated a clear picture of disciplinary variations and a strong tendency towards disciplinary specificity. More importantly, the results suggested that different methodological criteria played an important part, especially concerning the analysis of disciplinary specificity or generality. The choice of ‘4-word’ bundles over ‘3-word’ bundles, in particular, would tend to be associated with a result of a higher degree of disciplinary specificity. Regarding disciplinary variations, it was found that the effect from different choices of bundle extraction criteria was relatively smaller. Only the choice on different dispersion requirements could predict the significant differences between certain disciplines. These findings provide support for disciplinary variations and new perspectives on the disciplinary specificity-generality debate.