Patent ID: 7493257

Claim:
An apparatus handling speech recognition errors in a spoken dialogue system, comprising: a speech recognition unit extracting a speech feature of a speech signal inputted from a user and finding a phoneme nearest to the speech feature to recognize a word; a recognition error determination unit finding a sentence confidence based on a confidence of the recognized word, inspecting a semantic structure of a recognized sentence, and determining whether an error exists in the recognized sentence which is subject to speech recognition according to a predetermined criterion based on both the sentence confidence and a result of inspecting the semantic structure of the recognized sentence; and a meta-dialogue generation unit generating a question questioning the user about the recognized sentence based on a content of a portion where the error exists and a type of the errors, wherein the question is adapted so that, after both a confidence θ 2 determined that each word is a correct answer and another confidence θ 1 determined that each word is an incorrect answer are obtained, the word is substituted by an interrogative when the confidence of each recognized word is less than θ 1 , the word is omitted without repetition when the confidence of each recognized word is greater than θ 2 , and a phrase of the recognized word is repeatedly questioned when the confidence of each recognized word is greater than or equal to θ 1 , and is less than or equal to θ 2 .