Method and system for dynamically adjusted training for speech recognition

A method in a computer system for dynamically selecting words for training a speech recognition system, the speech recognition system for recognizing a plurality of words, the speech recognition system having indications of phonetic units that compose each word, the speech recognition system representing speech as a sequence of feature vectors, the speech recognition system having model for each phonetic unit, each model for generating a probability that each possible sequence of feature vectors corresponds to the modeled phonetic unit, the method comprising:

• collecting a plurality of spoken utterances for which the corresponding word is known;
• for each collected utterance,
• converting the collected utterance to a sequence of feature vectors;
• and
• aligning each feature vector in the sequence of feature vectors with a phonetic unit of the known word to which the collected utterance corresponds based on the models of the phonetic units of the known word;
• identifying from the feature vectors aligned with each phonetic unit a phonetic unit that is not accurately modeled;
• and
• selecting words that contain the identified phonetic unit as words for training the speech recognition system.

A method in a computer system for tutoring a speaker on pronunciation of words, each word being phonetically represented by phonetic units, each spoken utterance being represented by a sequence of feature vectors, each phonetic unit having a model for generating a probability that various sequences of feature vectors corresponds to the modeled phonetic unit, the method comprising:

• collecting a plurality of spoken utterances from the speaker for which the corresponding word is known;
• for each collected utterance,
• converting the collected utterance into a sequence of feature vectors;
• and
• aligning each feature vector in the sequence of feature vectors with a phonetic unit of the known word to which the collected utterance corresponds based on the model of the phonetic units of the known word;
• identifying, from the feature vectors aligned with each phonetic unit, a phonetic unit that is inaccurately spoken by the speaker;
• and
• selecting words that contain the identified phonetic units as words for tutoring the speaker.

A method in a computer system for selecting words for training a speech recognition system, the speech recognition system for recognizing a plurality of words, each word being spoken with phonetic units, the method comprising:

• receiving a plurality of spoken utterances for which the corresponding word is determined;
• for each phonetic unit of each of the determined words for which a spoken utterance is received, determining a context-dependent accuracy of the speech recognition system at recognizing the phonetic unit within the determined word;
• for each phonetic unit, determining a context-independent accuracy of the speech recognition system at recognizing the phonetic unit based on the context-dependent accuracies;
• and
• selecting words that contain phonetic units that are determined to have a lowest context-independent accuracy for training the speech recognition system.

A computer-readable medium containing instructions for causing a computer system to tutor a speaker on pronunciation of words, each word being spoken with phonetic units, by performing the steps of:

• receiving from the speaker a plurality of spoken utterances for which the corresponding word is known;
• identifying from the spoken utterances which phonetic units are inaccurately spoken by the speaker;
• and
• selecting words that contain an identified phonetic unit for tutoring the speaker.

A computer-readable medium containing instructions for causing a computer system to select words for training a speech recognition system, the speech recognition system for recognizing a plurality of words, the speech recognition system having a indication of phonetic units that compose each word, the speech recognition system having a model for each phonetic unit, the speech recognition system representing speech as a sequence of feature vectors, each model for indicating a probability that each possible sequence of feature vectors corresponds to the modeled phonetic unit, by performing the steps of:

• receiving a plurality of spoken utterances for which the corresponding word is determined;
• for each collected utterance,
• converting the collected utterance to a sequence of feature vectors;
• and
• aligning each feature vector in the sequence of feature vectors with a phonetic unit of the determined word to which the collected utterance corresponds based on the model of the phonetic units of the determined word;
• identifying from the feature vectors aligned with each phonetic unit which phonetic units are least accurately modeled;
• and
• selecting words that contain the identified phonetic units as words for training the speech recognition system.

A method in a computer system for dynamically selecting words for training a speech recognition system, each word comprising phonetic units, the method comprising:

• collecting a plurality of spoken utterances for which the corresponding word is known;
• identifying from the spoken utterances which phonetic units are inaccurately modeled by the speech recognition system;
• and
• selecting words that contain an identified phonetic unit for training of the speech recognition system.

A computer system for dynamically selecting words for training a speech recognition system, each word comprising phonetic units, comprising:

• a sample collecting component that collects a plurality of spoken utterances for which the corresponding word is known and converts the spoken utterances to codewords;
• an aligning component that aligns codewords with phonetic units of each word;
• a phonetic unit ranking component that identifies from the spoken utterances which phonetic units are inaccurately modeled by the speech recognition system based on the aligned codewords;
• and
• a word selection component that selects words that contain a phonetic unit identified by the phonetic unit ranking component for training of the speech recognition system.