Interactive Document Expansion for Answer Extraction of Question Answering System

In this paper, we propose a method to navigate getting a correct answer for Question Answering (QA) system using user interaction. QA is a technology which extracts appropriate answer strings for a given question sentence from huge documents such as Web, newspaper articles etc. If a given question is ambiguous, answers will be various ones according to its possible understandings and retrieved documents with query words of the question sentence will consists of various types of information. In order to focus on intended topic, it is necessary to provide more information to narrow down search area for a question. In our approach, a QA system selects a clue word to decide an appropriate topic from topics in retrieved documents and interacts with a user whether this clue word is appropriate one or not. Then, search space will be reduced using this clue word. However, such narrowing down reduces the number of answer candidates because the number of target documents will be decreased. We will re-retrieve documents using this clue words and expand search space to increase possibility of getting correct answer candidates. (C) 2013 The Authors. Published by Elsevier B.V.