1. Field of the Invention
The present invention relates to an automatic answering method and apparatus for supporting a question reply process of replying to a question document of a text format.
2. Description of the Related Art
With recent widespread of computerization, questions to companies or the like are often made by form inputs at home pages or e-mails. If every question is to be answered manually on the company side, many operators are required and the cost increases. A novice operator can not answer some questions or it takes a long time for the novice operator to answer a question. In order to solve this problem, a question-answering system has been introduced recently. With this system, a question document is input and its content is analyzed to select a reply example candidate from reply examples and question-reply examples prepared for each question content and to present the selected reply example candidate.
Most of such question-answering systems assume, however, that one document contains only one consultation content. Therefore, if a plurality of question contents are written in one document, the systems cannot analyze each question content, resulting in a low reply precision.
Another technique is disclosed in JP-A-2002-132661. This technique discloses means for dividing one document containing a plurality of question contents, into each question content. The divided question content is analyzed to select a reply example candidate. A reply precision representative of a likelihood or degree of each reply example candidate for the question content is calculated. If the reply precision has a predetermined value or higher, an answer is formed from the reply example candidate, whereas if the reply precision is lower than the predetermined value, an instruction is given to compose a new answer.
The conventional technique disclosed in JP-A-2002-132661 describes that the means for dividing a document into each question content performs a division process by using “number”, “alphabet”, “.”, an indent, a conjunction such as “or”, and the like. However, if a document is divided into each question content by using “number”, an indent and the like as a separator, there occurs the problem that one question content is divided into a plurality of sentences. Conversely, there arises the problem that if the range of a question content is broad, example candidates for a plurality of question contents cannot be selected.
According to conventional techniques, since a question document is divided basing upon only the information about the contents of the question document, the divided range may not be covered by each reply example candidate. Namely, it is necessary to divide a question document so as to be covered by a prepared reply example candidate, and not to divide it by referring only to the question document content.
Since a question document divided basing upon conventional techniques may be a document irrelevant to the question document content, the reply example candidate generation process is adversely affected so that the reply example candidate generation precision lowers. It also takes a time for a reply composition operator to find a proper document to be read.
According to conventional techniques, a reply precision representative of the likelihood value of a reply example candidate is calculated, and if the reply precision is a predetermined value or higher, a reply is generated from the reply example candidate to automatically answer (automatically return) the question. If the reply precision is lower than the predetermined value, an instruction is given to compose a new answer. However, if there are a large number of types of replies or if a similar question requires a different answer, the reply precision lowers so that the number of samples exceeding a predetermined threshold reduces. Therefore, the number of samples capable of being used for the automatic reply reduces, and the number of cases requiring to generate new answers increases. There arises the problem of a low operator work efficiency or an automatic reply using an erroneous reply example candidate.