A Computational Account of Tone Sandhi Interaction

Abstract

This paper presents a computational account of three tone sandhi rules in Tianjin Chinese that have received a lot of attention in the literature due to the seemingly complex way in which they interact. Two of the rules apply right-to-left while the third applies left-to-right, making it difficult for both rule- and constraint-based formalisms to account for the interaction in a unified way. In the computational framework advocated for in this paper, the apparent difference in directionality of the three rules amounts to a subtle difference in computational classification: the left-to-right rule has the property of input strict locality (ISL) while the right-to-left rules share the property of output strict locality (OSL). However, the fact that the direction of rules with the ISL property doesn't actually matter, a unified account becomes possible in that all three rules can be modeled as a single input-output strictly local function.