[PS-2.70] Syntactic Argument Prediction as Anticipatory Structure Building

Schumacher, R. & Yoshida, M.

Northwestern University

Verbal subcategorization frames are strong contributors to parsing, but it is unclear if subcategorization can be used to build structure anticipatorily. We investigated how filler-gap dependency formation interacts with subcategorization using verbs which obligatorily select PP arguments (rely on). If the parser uses subcat-frames actively, such a verb may lead the parser to predictively project the PP-structure upon encountering the verb, before encountering the preposition. Alternatively, subcategorization may influence only semantic processing, expecting the upcoming preposition only. In a wh-sentence, where the parser resolves a wh-dependency reveals whether a predicted PP is the preferred gap site. We conducted an eye-tracking experiment with PP-taking verbs, where the complement PP was dislocated by an adjunct PP or adjacent to it (rely with urgency on NP/on NP with urgency). A filled adjacent PP would induce a filled-gap effect if the wh-dependency was resolved there. No filled-gap effect appeared with adjacent adjuncts, unlike with predicted PPs. This means that the parser resolved the dependency in the predicted PP before encountering it, because it did not try to resolve it in the adjunct in spite of the fact that extraction from such adjunct PPs is possible. This demonstrates anticipatory syntactic structure building via subcategorization.