STATISTICAL DATABASE CORRECTION OF ALPHANUMERIC ACCOUNT NUMBERS FOR SPEECH RECOGNITION AND TOUCH-TONE RECOGNITION

A method and apparatus for recognizing an identifier entered by a user. A caller enters a predetermined identifier through a voice input device or a touch-tone keypad of a telephone handset. A signal representing the entered identifier is transmitted to a remote recognizer, which responds to the identifier signal by producing a recognized output intended to match the entered identifier. The present invention compares this recognized identifier with a list of valid reference identifiers to determine which one of these reference identifiers most likely matches the entered identifier. In performing this determination, the present invention employs a confusion matrix, which is an arrangement of probabilities that indicate the likelihood that a given character in a particular character position of the reference identifier would be recognized by the recognizer as a character in the corresponding character position of the recognized identifier. This determination yields an identifier recognition probability for every reference identifier, and the present invention selects the reference identifier with the highest identifier recognition probability as most likely corresponding to the entered identifier.