Blurb:

Constraints on Binarity are commonly used to capture size effects: the tendency for longer strings to be parsed into more prosodic constituents. In some implementations, binarity is assessed locally by counting immediate children (= branch-counting); in others, binarity is assessed globally by counting all descendants of some category (= leaf-counting). Branch-counting binarity motivates size-driven prosodic recursion, and operates as a special case of Match(XP). In contrast, leaf-counting binarity motivates size-driven category promotion, and conflicts with Match(XP), leading to larger typology sizes. A constraint on Uniformity is shown to be able to derive size-driven mismatches as well.