The final session today at the AoIR 2025 conference starts with my excellent QUT colleague Tariq Choucair, who begins by introducing the challenge of assessing polarisation: there are many different definitions of polarisation, which require different measures of assessment. Most current methods fail to sufficiently distinguish between these types of polarisation.
Tariq is therefore proposing a new approach to assessing polarisation, which he has applied to the study of national electoral contests in Australia, Brazil, Denmark, and Peru. The focus here is to identify polarising rhetoric, including campaign attacks, and polarisation in broader public debates.
The method focusses especially on references to in- and out-groups in political rhetoric; it examines different levels of affiliation and opposition in polarising rhetoric directed at these groups. It works by identifying actors and groups that are mentioned in the rhetoric of political actors, and classifies these mentions on a seven-step scale from hard affiliation to hard opposition. An aggregation of these classifications then enables the assessment of polarisation in political discourse.
The particular focus here is on pernicious or destructive levels of polarisation. For each political actor, it is possible to examine their distribution of references that represent the various forms of affiliation and opposition; some actors may focus only on strong affiliations with their in-group, while others also refer frequently to out-group actors and express high levels of opposition.
Two aspects are key here: the extremity of differences is especially critical as a sign of deep polarisation, while the amount of attention given to the out-group is a sign of the emphasis of such polarising references. Who these in- and out-groups represent is also important, of course: does polarising rhetoric address specific political opponents, exclude whole societal groups, or focus on international actors?
