Method of indexing and retrieval of electronically-stored documents

Abstract

A document indexing and retrieval system and method which assigns weights to the key words and assigns a relative value to pairs of key words (i.e. defines a relative relation on KxK) based on their frequency of occurrence and co-occurrence in the document data base. In response to a query both the weights and this relative relation are used to suggest additional and/or alternative key words which are very likely to find relevant documents. Documents are then ranked by number of hits adjusted for the weights of hit words and their relative values.

Description

BACKGROUND OF THE INVENTION1. Field of the InventionThis invention relates generally to document storage and retrieval systems and more particularly to a method of indexing documents so that they can be retrieved in response to a query in order of their relevance to the query. It also permits, general query to be easily modified based on the content of the documents so that the new query will retrieve documents that are relevant to the original query.2. Description of the Prior ArtDocument retrieval based on indexing of the documents in a document data base is well known. Typically the documents are indexed by creating an index file which records the documents that each word is in. Then when the user inputs a query, the documents that contain one or more words of the query can be quickly identified. However, if the query consists of general words that are not terms of art, the query may produce unsatisfactory retrieval results by either producing few documents that are of interest t...

AI Technical Summary

Benefits of technology

The present invention facilitates the rapid searching of a document data base for documents that are of interest to the user. By using the suggested SWAPS terms the user can modify his query so as to retrieve those documents, if they exist in the data base, which are of interest. Since the SWAPS terms that are presented are in many of the documents that the original query terms are in, adding them to the query is guaranteed to retrieve those documents and others containing the SWAPS terms. By using the SWAPS feature repeatedly the user can in effect roam around the data base without actually retrieving and reading documents. Only after the query has been modified to include all the interesting SWAPS terms, does the user need to actually retrieve the documents. The user can start with a poor query and modify it using SWAPS so that it becomes a good query. The user need not waste time formulating a good query that will not retrieve any relevant documents because there happen to be no such documents in the data base. The SWAPS terms that are suggested will always retrieve documents that contain them i.e. documents that are likely to be relevant.

The ranking of the documents also facilitates rapid searching because the user can be confident that the highest ranked documents will be the

Problems solved by technology

However, if the query consists of general words that are not terms of art, the query may produce unsatisfactory retrieval results by either producing few documents that are of interest to the user or producing many documents that are not interesting to the user or both.

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