Keyness Analysis: nature, metrics and techniques

This chapter discusses methodological issues relating to keyness analysis, and addresses a number of this volume’s interconnected themes. It raises awareness of relevant methodological choices and their implications, and addresses related misconceptions and resulting practices, particularly regarding the selection of linguistic units, appropriate metrics, and thresholds of frequency, effect-size and statistical significance. It also discusses the pervasive partiality (Marchi & Taylor, this volume) in keyness analysis, as the vast majority of keyness studies focus on difference, at the expense of similarity. Finally, it discusses the tension between objectivity and subjectivity in relation to methodological choices, and problematises the frequent conflation of quantitative analysis and objectivity. In order to better understand and evaluate the current state of keyness research, however, we need to contextualise current views and practices. Therefore, the chapter will start with a critical overview of the brief history of keyness analysis.