Palfreyman, Nick (2014) Applying lexicostatistical methods to sign languages: How not to delineate sign language varieties. Unpublished paper available from clok.uclan.ac.uk/37838 Applying lexicostatistical methods to sign languages: How not to delineate sign language varieties.1 Nick Palfreyman (
[email protected]) International Institute for Sign Languages and Deaf Studies, University of Central Lancashire. The reliability and general efficacy of lexicostatistical methods have been called into question by many spoken language linguists, some of whom are vociferous in expressing their concerns. Dixon (1997) and Campbell (2004) go as far as to reject the validity of lexicostatistics entirely, and Dixon cites several publications in support of his argument that lexicostatistics has been ‘decisively discredited’, including Hoijer (1956), Arndt (1959), Bergslund and Vogt (1962), Teeter (1963), Campbell (1977) and Embleton (1992). In the field of sign language research, however, some linguists continue to produce lexicostatistical studies that delineate sign language varieties along the language-dialect continuum. Papers referring to lexicostatistical methods continue to be submitted to conferences on sign language linguistics, suggesting that these methods are – in some corners of the field, at least – as popular as ever. Given the ongoing popularity of lexicostatistical methods with some sign language linguists, it is necessary to be as clear as possible about how these methods may generate misleading results when applied to sign language varieties, which is the central aim of this paper. Furthermore, in several cases, lexicostatistical methods seem to have been deployed for a quite different purpose – that of establishing mutual intelligibility – but the suitability of lexicostatistical methods for such a purpose has not been openly addressed, and this is dealt with in Section 4.