Identifying reliable, valid markers of authorship: a response to Chaski

In response to Chaski’s article (published in this volume) an examination is made of the methodological understanding necessary to identify dependable markers for forensic (and general) authorship attribution work. This examination concentrates on three methodological areas of concern which researchers intending to identify markers of authorship must address. These areas are sampling linguistic data, establishing the reliability of authorship markers and establishing the validity of authorship markers. It is suggested that the complexity of sampling problems in linguistic data is often underestimated and that theoretical issues in this area are both difficult and unresolved. It is further argued that the concepts of reliability and validity must be well understood and accounted for in any attempts to identify authorship markers and that largely this is not done. Finally, Principal Component Analysis is identified as an alternative approach which avoids some of the methodological problems inherent in identifying reliable, valid markers of authorship.