In this paper we propose and evaluate a soft computing-based passage retrieval system for Question Answering Systems (QAS). FuzzyPR, our base-line passage retrieval system, employs a similarity measure that attempts to model accurately the question reformulation intuition. The similarity measure includes fuzzy logic-based models that evaluate efficiently the proximity of question terms and dete...

Information Retrieval Systems aim at retrieving relevant documents according to the information needs which users express. Most Information Retrieval Systems focus on passage retrieval where the granularity of information retrieved is not the document but a smaller unit such as a sentence or passage. These systems try to better answer the users’ needs by giving more importance to the most relev...

We show that several previously proposed passage-based document ranking principles, along with some new ones, can be derived from the same probabilistic model. We use language models to instantiate specific algorithms, and propose a passage language model that integrates information from the ambient document to an extent controlled by the estimated document homogeneity. Several document-homogen...

One of the major challenges for spoken document retrieval is how to handle speech recognition errors within the target documents. Query expansion is promising for this challenge. In this paper, we apply relevance models, a type of query expansion method, for the spoken document passage retrieval task. We adapted the original relevance model for passage retrieval. We also extended it to benefit ...

In this paper, we give an overview of our questionanswering system for the NTCIR-3 QAC. Our system is based on an information-retrieval technique and an information-extraction technique by pattern matching. The system has three main stages: question analysis, passage retrieval, and answer extraction. In the passage-retrieval stage, two types of retrieval method are applied sequentially to narro...

For the TREC-2006 Genomics Track, we report on the effectiveness of composite information retrieval functions based on a dimensional data model for improving document, passage, and aspect search precision of genomics literature. We designed an approach, and developed a corresponding search engine, based on a novel dimensional data model capable of document, paragraph, sentence, and passage leve...

This paper describes our system and additional experimental results in NTCIR-4 QAC Task 1. The main components of our system are question classification, passage retrieval, and named entity extraction. Passage retrieval was performed by a density-based ranking method based on importance of query terms occurred in the passage. Question classification and Named entity extraction were designed by ...