Simulating vowel chain shift in Xumi

International audienceThis paper presents a simulation study of a vowel chain shift in Xumi (Tibeto-Burman). It adapts de Boer’s (2000, 2001) model of vowel systems in a population of artificial agents. The goals are: (1) to test one specific hypothesis of the relevance of a loan phoneme to the observed changes in the chain shift, and (2) to address on the basis of our Xumi data some general questions of interpretation related to synchronic vowel chain shifts. Our simulation results shed light on a complex scenario of change in Xumi that involves both system- internal factors and a system-external factor (the addition of a loan phoneme). Our simulation results also suggest that the particular combination of mechanisms and constraints in the model’s settings---random acoustic noise, self-organization, and contrast mainte- nance---is a viable hypothesis for vowel chain shifting. Our study demonstrates that computational simulations are helpful in evaluating different approaches to a specific instance of sound change