16. A system for detecting repeated patterns in a dialog system, comprising: a speech recognizer hardware component receiving an initial utterance from a user in the dialog sequence as a set of test patterns, and receiving a correction utterance from the user in response to an output from a response generator of the dialog system, wherein the initial utterance includes a first plurality of words in a first order and the correction utterance includes a second plurality of words in a second order, wherein at least some of the second plurality of words are repeated from the first plurality of words; an event detector hardware component detecting the occurrence of repeated segments between the initial utterance and the correction utterance; a segmentation hardware component segmenting the correction utterance into a set of reference patterns by identifying silence regions separating each of the first plurality of words within the initial utterance; a feature extraction hardware component extracting feature vectors from the test patterns and the reference patterns; and a pattern comparison component of the event detector comparing each test pattern with each reference pattern over the entire length of the set of test patterns and the set of reference patterns, using a dynamic time warping process in order to determine boundaries of the reference and test patterns using spectral characteristics of the initial and correction utterances, and computing distance scores between each reference pattern and each test pattern to identify test patterns with a distance score of less than a defined distance threshold as a repeated pattern.
17. The system of claim 16 further comprising a decision rule hardware component defining the distance threshold.