tailieunhanh - Báo cáo khoa học: "Kernel-Based Pronoun Resolution with Structured Syntactic Knowledge"

Syntactic knowledge is important for pronoun resolution. Traditionally, the syntactic information for pronoun resolution is represented in terms of features that have to be selected and defined heuristically. In the paper, we propose a kernel-based method that can automatically mine the syntactic information from the parse trees for pronoun resolution. Specifically, we utilize the parse trees directly as a structured feature and apply kernel functions to this feature, as well as other normal features, to learn the resolution classifier. In this way, our approach avoids the efforts of decoding the parse trees into the set of flat syntactic features | Kernel-Based Pronoun Resolution with Structured Syntactic Knowledge Xiaofeng Yang Institute for Infocomm Research 21 Heng Mui Keng Terrace Singapore 119613 xiaofengy sujian @ Jian Sil Chew Lim Tan Department of Computer Science National University of Singapore Singapore 117543 tancl@ Abstract Syntactic knowledge is important for pronoun resolution. Traditionally the syntactic information for pronoun resolution is represented in terms of features that have to be selected and defined heuristically. In the paper we propose a kernel-based method that can automatically mine the syntactic information from the parse trees for pronoun resolution. Specifically we utilize the parse trees directly as a structured feature and apply kernel functions to this feature as well as other normal features to learn the resolution classifier. In this way our approach avoids the efforts of decoding the parse trees into the set of flat syntactic features. The experimental results show that our approach can bring significant performance improvement and is reliably effective for the pronoun resolution task. 1 Introduction Pronoun resolution is the task of finding the correct antecedent for a given pronominal anaphor in a document. Prior studies have suggested that syntactic knowledge plays an important role in pronoun resolution. For a practical pronoun resolution system the syntactic knowledge usually comes from the parse trees of the text. The issue that arises is how to effectively incorporate the syntactic information embedded in the parse trees to help resolution. One common solution seen in previous work is to define a set of features that represent particular syntactic knowledge such as the grammatical role of the antecedent candidates the governing relations between the candidate and the pronoun and so on. These features are calculated by mining the parse trees and then could be used for resolution by using manually designed rules Lappin and Leass 1994