Experiments with query expansion in the RAPOSA (FOX) question answering system

• Type: Article in International Conference Proceedings Book
• Date: 2008

Authors

Luís António Diniz Fernandes de Morais Sarmento (Author) FEUP; Jorge Filipe Pinheiro Guerra de Ribeiro Teixeira (Author) FEUP; Eugénio da Costa Oliveira (Author) FEUP

Conference proceedings International

Title: The Cross-Language Evaluation Forum (CLEF)

Pages: 1-12

Aarhus, Denmark, 17 a 19 Setembro

Indexing

Scopus - 0 Citations

Scientific classification

FOS: Engineering and technology > Electrical engineering, Electronic engineering, Information engineering

CORDIS: Humanities > language sciences > Linguistics ; Technological sciences > Engineering

Other information

Authenticus ID: P-00A-4M3

Abstract (EN): In this paper we present the results of applying a statistical query expansion method on the retrieval stage of a QA system for Portuguese (RAPOSA). Our approach in- volves expanding queries for event-related or action-related factoid questions using a verb thesaurus automatically generated using information extracted from large cor- pora. We show that our expansion approach improves QA recall when compared with applying expansion based on a simple form of stemming, while simultaneously requir- ing the analysis of only 30% as many text snippets. However, we were not able to outperform the recall obtained using an even simpler expansion method, which never- theless achieves lower precision and requires analyzing many more text snippets. We conclude by observing that a more thorough analysis of the usefulness of our approach on QA performance requires improving other stages of the QA pipeline which currently impose significant limitations on the overall performance of the system.

Language: English

Type (Professor's evaluation): Scientific