Recent work under the theoretical banner of Agreement by Correspondence (ABC) has produced a variety of different – and sometimes contradictory – formulations of the constraints central to this framework. In OT, the effects of such definitional choices come out in the factorial typologies they predict. Yet knowing what languages a theoretical system derives is insufficient unless we know why it does so. This requires analysis of the internal ranking structures of the typology itself. This paper compares the typologies produced under different proposed modifications to the main ABC constraints. We analyse the typologies in Property Theory, a theory of typological organisation in OT. Our analyses show that all variations have a common core structure, and that differences in their factorial typologies reduce to differences in how this common structure expands and iterates for different features. This allows for precise delineation of how and why different ABC constraint definitions affect typologies.

The most comprehensive work on dissimilation (the avoidance or repair of combinations of similar sounds) to date, this book proposes a novel analysis that handles dissimilation as the avoidance of surface correspondence relationships. It draws on recent work in Agreement By Correspondence to show that dissimilation is a natural outcome predicted by the same theory of Surface Correspondence. The theory is developed in more detail than ever before, and its predictions are tested and evaluated through ten in-depth analyses of diverse languages from Quechua to Kinyarwanda, together with a typological survey of over 150 dissimilation patterns drawn from over 130 languages, from Acehnese to Zulu. The book redefines the core of Surface Correspondence theory to a level of formal specificity and theoretical precision surpassing previous work. The book's findings are made more accessible by numerous examples featuring data from 47 languages from around the world.

This paper reports on a pattern of voicelessness dissimilation in the Kordofanian language Moro. Voiceless stops and affricates become voiced before a voiceless obstruent in a transvocalic configuration. The dissimilation is robust, and productive across morphological contexts. Phonetically, voicing in Moro is realised as a difference between prevoicing and short-lag voice onset time. This makes [voice] the most realistic featural characterisation; using another feature like [spread glottis] in lieu of [–voice] doesn't explain the contrast. Consequently, dissimilation of voicelessness in Moro is strong evidence that [voice] is a binary feature, and that […voice] may be phonologically active despite being ‘unmarked’. We show that when [–voice] is admitted, the Moro pattern is straightforwardly analysed on a par with other cases of dissimilation. Our analysis uses the theory of surface correspondence, which carries no crucial assumptions about markedness; other theories of dissimilation are considered in an online supplement.