Modeling linguistic evolution: a look under the hood

Abstract

This paper takes a detailed look at some popular models of evolution used in contemporary diachronic linguistic research, focusing on the continuous-time Markov model, a particularly popular choice. I provide an exposition of the math underlying the CTM model, seldom discussed in linguistic papers. I show that in some work, a lack of explicit reference to the underlying computation creates some difficulty in interpreting results, particularly in the domain of ancestral state reconstruction. I conclude by adumbrating some ways in which linguists may be able to exploit these models to investigate a suite of factors which may influence diachronic linguistic change.