Unsupervised and active learning in automatic speech recognition for call classification

A system comprising:

• an automatic speech recognizer configured to automatically transcribe utterance data not having a corresponding manual transcription and produce a set of automatically transcribed data;
• a learning module configured to intelligently select a predetermined number of utterances from the set of automatically transcribed data, the selected number of predetermined utterances to be manually transcribed, added to a set of manually transcribed data, and deleted from the set of automatically transcribed data;
• a training module configured to train a language model using the set of manually transcribed data and the set of automatically transcribed data;
• and
• a labeler to label at least some of the set of automatically transcribed data and the set of manually transcribed data.

A system comprising:

• means for performing automatic speech recognition on ones of a plurality of utterance data not having a corresponding manual transcription to produce automatically transcribed utterances;
• means for training a language model using manually transcribed data and the automatically transcribed utterances;
• means for intelligently selecting, for manual transcription, a predetermined number of utterances not having a corresponding manual transcription from the utterance data;
• and
• a labeler to label ones of the automatically transcribed data as well as ones of the manually transcribed data.
• means for coordinating activities such that the means for performing automatic speech recognition, the means for training a language model, and the means for intelligently selecting repeatedly perform corresponding activities until word accuracy of the means for performing automatic speech recognition converges,
• wherein the labeler is to label ones of the automatically transcribed data as well as ones having a corresponding manual transcription after the word accuracy converges.

A machine-readable medium having a plurality of instructions recorded thereon, the instructions comprising:

• instructions for performing automatic speech recognition on ones of a plurality of utterance data not having a corresponding manual transcription to produce automatically transcribed utterances;
• instructions for training a model using manually transcribed data and the automatically transcribed utterances;
• instructions for intelligently selecting, for manual transcription, a predetermined number of utterances, from the utterance data, not having a corresponding manual transcription;
• instructions for receiving new manually transcribed data;
• and
• instructions for permitting labeling of ones of the automatically transcribed data as well as ones of the manually transcribed data.

An apparatus comprising:

• a processor;
• and
• storage to store instructions for the processor, wherein the processor is configured to:
• mine audio data from at least one source, and
• train a language model for call classification from the mined audio data to produce a language model.