ABSTRACT
In this chapter, the authors show how research writing may have changed in terms of the main communicative functions expressed by writers. They utilize D. Biber’s multidimensional analysis, assuming that the linguistic and functional content of the dimensions it identifies indicate changes in rhetorical practices over time. The authors introduce the multidimensional analysis model before discussing their results. Multidimensional analyses are typically used to investigate the variations across registers in English and world Englishes, examining cross-linguistic similarities and differences in the patterns of register and genre variation. The authors present Multidimensional Analysis Tagger to analyse disciplinary changes in the mean scores of each dimension across the years. Functional dimensions of discourse are marked out by the co-occurrence of linguistic features, underlining differences in the communicative focus of genres. Applied linguistics and sociology have strengthened their informational focus, shown by the use of nouns, prepositions, attributive adjectives and longer words.
