INTEGRATION OF NOMINAL PREDICATES INTO A PARSER: AN EXPERIMENT WITH THE CONSTRUCTIONS WITH THE SUPPORT VERB DAR ‘GIVE’ IN BRAZILIAN PORTUGUESE

ABSTRACT This article describes the methodology for the integration of nominal predicates, that is, support verb constructions (SVC), in the XIP parser, which is used by STRING, a Portuguese processing chain. More specifically, 580 SVC with the support verb (Vsup) dar ‘give’ and a predicative noun (Npred), whose syntactic-semantic properties have been described, formalized and then integrated into the Portuguese grammar of XIP, by means of rules, in order to extract the syntactic dependency (noted SUPPORT) between the Npred and the Vsup. The need to automatically treat SVC derives from the fact that they are different from full-verb constructions, have complex syntactic structures, have specific syntactic-semantic properties, and allow several systematic, albeit lexically determined, syntactic transformations. The concept of SVC, as well as the lexical-syntactic approach here adopted, follows the theoretical and methodological principles of the Lexicon-Grammar theory. As a result of integrating these data into the XIP parser, the system achieved 85% precision, 87% recall, 80% accuracy and 86% F-measure on an evaluation corpus, specifically built for this purpose.

摘要 本文阐述了将名词性谓词（即支撑动词构式（support verb constructions，SVC））集成至葡萄牙语自然语言处理流水线STRING所使用的XIP句法分析器（XIP parser）的方法论。具体而言，本文针对580个由支撑动词（support verb，Vsup）dar（义为“给予”）与谓词性名词（predicative noun，Npred）构成的SVC，在完成其句法语义属性的描述、形式化后，通过规则将其集成至XIP的葡萄牙语语法体系，以提取谓词性名词与支撑动词之间标注为SUPPORT的句法依存关系。自动处理支撑动词构式的必要性源于：此类构式不同于实义动词构式，具备复杂的句法结构与特定的句法语义属性，且允许存在若干尽管由词汇限定但具有系统性的句法变换。本文所采用的支撑动词构式概念及词汇-句法研究路径，遵循词汇-语法理论（Lexicon-Grammar theory）的理论与方法论原则。将上述数据集成至XIP句法分析器后，系统在专为本次评测构建的语料库上取得了85%的精确率、87%的召回率、80%的准确率以及86%的F测度（F-measure）。