Feature percolation, unary features, and the coordination of English NPs

ConclusionSGWW's adoption of unary features creates a range of problems. The general problems affecting feature percolation can be cured by minor redefinitions of the relevant principles. But if we wish to maintain SGWW's attractive position that the syntax of coordination depends on fully general principles which extend directly to cover person categories in NP coordination, while the distinctive behaviour of number in such coordination follows from properties of the phrases which introduce specific conjunctions, then something further is required. A straightforward solution, which will have implications for the treatment of person, number and gender in other languages, is to retain orthodox features with more than one value and modify the scope of feature percolation by permitting the Head Feature Convention to hold for specific, probably unmarked, feature values. This imports the intended effect of unary feature specification into the workings of feature percolation.