Agreement and Disagreement of Vowel Features: Mid Vowel Assimilation in Yanggu

This study proposes an Optimality-Theoretic account of Yanggu mid vowel assimilation, and demonstrates that the interaction of markedness constraints and harmony-related constraints provides a unified analysis. Within the framework of Optimality Theory (Prince and Smolensky 1993), assimilation and harmony can be treated as feature agreement within a phonological or morphological domain, and any feature disagreement or disharmony within the domain is attributed to the restrictions set by markedness constraints (Cole and Kisseberth 1994, 1995, Padgett 1995, 1996). The proposed constraint-based analysis of Yanggu mid vowel assimilation posits two subsyllabic domains for vowel feature harmony, shows how markedness constraints bar the creation of marked, non-structure-preserving or universally prohibited segments, and argues that the constraint-based approach is superior to the traditional rule-based analysis in which several different but apparently related assimilation rules must be postulated.