The Relative Contribution of Syntactic and Semantic Prominence in Pronoun Reference Resolution

Subjects are preferred antecedents for pronominal reference (Mathews and Chodorow, 1988; Hudson-D’Zmura and Tanenhaus, 1997). Many pronoun resolution algorithms account for this by assuming a hierarchy of syntactic prominence with SUBJECTS > OBJECTS. However, for many verbs in English, syntactic role is conflated with semantic role: That is, syntactic SUBJECTS are often semantic AGENTS and so on. So what appears to be the result of the prominence of syntactic SUBJECTS might actually be the result of the prominence of semantic AGENTS over other semantic roles. A series of psycholinguistic experiments compare the influence of syntactic prominence and semantic prominence on the salience of antecedents for subsequent pronominal reference. Results show that both syntactic and semantic prominence are relevant factors and further suggest some revision to the long-assumed syntactic prominence hierarchy. The paper concludes with discussion of specific recommendations for the adaptation of computational models of discourse structure and pronoun resolution.