The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 16, 1989
Filed:
Mar. 27, 1986
Slava M Katz, Westport, CT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Apparatus and method for evaluating the likelihood of an event (such as a word) following a string of known events, based on event sequence counts derived from sparse sample data. Event sequences--or m-grams--include a key and a subsequent event. For each m-gram is stored a discounted probability generated by applying modified Turing's estimate, for example, to a count-based probability. For a key occurring in the sample data there is stored a normalization constant which preferably (a) adjusts the discounted probabilities for multiple counting, if any, and (b) includes a freed probability mass allocated to m-grams which do not occur in the sample data. To determine the likelihood of a selected event following a string of known events, a 'backing off' scheme is employed in which successively shorter keys (of known events) followed by the selected event (representing m-grams) are searched until an m-gram is found having a discounted probability stored therefor. The normalization constants of the longer searched keys--for which the corresponding m-grams have no stored discounted probability--are combined together with the found discounted probability to produce the likelihood of the selected event being next.