DOCUMENT RETRIEVAL SYSTEM AND QUESTION ANSWERING SYSTEM

摘要

PURPOSE: A document retrieval system and a question answering system are provided to retrieve accurately information requested from a user by classifying weight of keyword. CONSTITUTION: A query input section(102) receives a query input by a user. A keyword extraction section(104) analyzes the input query and extracts keywords. A keyword type assignment section(106) decides the type of each extracted keyword and assigns a keyword type. A question type decision section(108) decides the question type. A keyword classification section(110) classifies the keywords to which the keyword types are assigned into a major type and minor type with reference to the keyword classification rules stored in a keyword classification rule storage section(112). A document retrieval section(114) searches a document collection stored in a document storage section(116) using the classified keyword groups and obtains the document of the retrieved result.