Language variationists study how languages vary along geographical or social lines or along lines of age and gender. Variationist data is available and challenging, in particular for DIALECTOLOGY, the study of geographical variation, which will be the focus of this paper, although we present approaches we expect to transfer smoothly to the study of variation correlating with other extralinguistic variables. Techniques from computational linguistics on the one hand, and standard statistical data reduction techniques on the other, not only shed light on this classic linguistic problem, but they also suggest avenues for exploring the question at more abstract levels,.
