Study title

Research taking a computational approach to the analysis of online communications has thus far focused overwhelmingly on the structural elements of Computer Mediated Discourse (CMD), such as typography, orthography and other low level features, with little to no attention being paid to the socially situated discourses in which these features are embedded. The Centre for Forensic Linguistics (CFL) - a research centre within Aston University combining leading-edge research and investigative forensic practice - and Lexegesys - a consultancy and technology company specialising in developing and implementing data analysis solutions, recently collaborated on a project that was successful in automating the process of identification and extraction of low-level features for the purposes of attributing authorship of unknown texts within the context of Twitter. Yet CMD has widely been recognized to operate on a number of linguistic levels, such as those of meaning, of interaction, and of social practice. Outside of the computational linguistic field, the characteristic features of CMD are understood as resources that users draw on in the construction of identities in particular contexts, and CMD constitutes social practice in and of itself rather than simply being shaped by social variables. This data collection consists of transcripts of Instant Messaging conversations between a 'Judge' and an 'Interlocutor', the latter being replaced at some point by an 'Impersonator'. 3 x 15 minute chats per file, representing 3 conditions of preparation for the Impersonator in each case - No Preparation, Over the Shoulder preparation, and Homework preparation. The transcripts correspond to postgraduate students (files 1-12) and undergraduate students (files 13-30). Judges were asked to record when they thought a switch had taken place, what linguistic criteria led them to think this, and how confident they were in their decision. Information on when switches actually occurred was also...