TALP-UPC at TREC 2005: Experiments using voting scheme among three heterogeneous QA systems

Abstract

This paper describes the experiments of the TALP-UPC group for factoid and ’other’ (definitional) questions at TREC 2005 Main Question Answering (QA)task. Our current approach for factoid questions is based on a voting scheme among three QA systems: TALP-QA (our previous QA system), Sibyl (a new QA system developed at DAMA-UPC and TALP-UPC), and Aranea (a web-based data-driven approach). For defitional questions, we used two different systems: the TALP-QA Definitional system and LCSUM (a Summarization-based system). Our results for factoid questions indicate that the voting strategy improves the accuracy from 7.5% to 17.1%. While these numbers are low (due to technical problems in the Answer Extraction phase of TALP-QA system) they indicate that voting is a succesful approach for performance boosting of QA systems. The answer to definitional questions is produced by selecting phrases using set of patterns associated with definitions. Its results are 17.2% of F-score in the best configuration of TALP-QA Definitional system.