Resolving Ambiguities of Chinese Conjunctive Structures by Divide-and-conquer Approaches
Duen-Chi Yang, Yu‐Ming Hsieh, Keh-Jiann Chen · 2008
This paper presents a method to enhance a Chinese parser in parsing conjunctive structures. Long conjunctive structures cause long-distance dependencies and tre-mendous syntactic ambiguities. Pure syn-tactic approaches hardly can determine boundaries of conjunctive phrases properly. In this paper, we propose a divide-and-conquer approach which overcomes the dif-ficulty of data-sparseness of the training data and uses both syntactic symmetry and semantic reasonableness to evaluate am-biguous conjunctive structures. In compar-ing with the performances of the PCFG parser without using the divide-and-conquer approach, the precision of the con-junctive boundary detection is improved from 53.47 % to 83.17%, and the bracketing f-score of sentences with conjunctive struc-tures is raised up about 11 %. 1