We present a library of implemented HPSG analyses for argument optionality based on typological studies of this phenomenon in the world's languages, developed in the context of a grammar customization system that pairs a crosslinguistic core grammar with extensions for non-universal phenomena on the basis of user input of typological properties. Our analyses are compatible with multiple intersecting phenomena, including person, number, gender, tense, aspect and morphological rule formulation. We achieve 80-100% coverage on test suites from 10 natural languages.
Safiyyah Saleem, Emily M. Bender