Abstract: A method of identifying at least one query theme associated with a search query, wherein the query theme corresponds to a subject, person or place associated with the search query. A document record archive has a plurality of document records each of which is associated with a stored document. Each of the document records has a plurality of metadata fields each of which stores a numerical score representing a degree of correlation between the stored document associated with the document record and a document theme, wherein the document theme corresponds to a subject, person or place associated with the stored document. A results list is retrieved in response to the search query, the results list is formed of document records each of which is associated with the search query. A composite theme score is determined for each document theme represented by the metadata fields in the document records in the results list. Each of the plurality of composite theme scores is compared to a threshold.

Abstract: A system for parsing information representative of a sequence of words having parts of speech. The sequence of words forms a sentence or sentence fragment. A hidden Markov model is provided for determining the most likely part of speech of a selected word of the sequence of words. The hidden Markov model has an initial transition matrix and a subsequent transition matrix for storing probabilities of occurrence of the parts of speech. The initial transition matrix of the hidden Markov model is removed to provide a modified hidden Markov model. The modified hidden Markov model is applied to the sequence of words to determine the most likely part of speech of a selected word within a sentence fragment with increased accuracy.

Abstract: A method for performing a search of a database in an information retrieval system in response to a query having at least one query word with a query word weight and for applying the query word to the database and selecting information from the information retrieval system in accordance with the query word. A query word is selected and assigned a weight. The weight is adjusted depending on whether the query word is a proper noun or slow word. The adjusting can be an increase or a decrease in the weight. Information is selected from the information retrieval system in accordance with the adjusted weight.

Abstract: A method for searching a database of an information retrieval system in response to a query having at least one query word with a part of speech, for applying the query word to the database and selecting information from the database according to the query word. A semantic network is provided for determining expansion words to expand the search of the database in response to said the query word. The part of speech of the selected query word is determined. The selected query word is applied to the semantic network to provide a query expansion word in response to the selected query word. The part of speech of the query expansion word is determined. The query expansion word is applied to the database in accordance with the part of speech of the selected query word and the part of speech of the query expansion word.

Abstract: A method for storing input information in an information retrieval system database wherein a plurality of information subject categories are provided. A plurality of subject lexicons are provided, each subject lexicon of the plurality of subject lexicons corresponding to an information subject category of the plurality of information categories. Each subject lexicon contains information representative of its corresponding information subject category. The input information is compared with the subject lexicons and the input information is stored in a selected information subject category according to the comparing of the input information with the subject lexicons.

Abstract: A method for searching a database of an information retrieval system in response to a query having a query length of at least one word, for applying the query word to the database and selecting information from the database according to the query word. The query is received and the length of the query is determined. Information is selected from the database according to the query. The relevance of the selected information is determined according to matches between the query and the information. The determined relevance of the selected information is adjusted according to the length of the query.