12. A method of adjusting a voice prompt of a system based upon a state of a user of the system, the method comprising: receiving an utterance of the user; obtaining utterance parameters from the utterance, the utterance parameters indicating the state of the user; generating an utterance parameter vector based upon the obtained utterance parameters; converting the utterance parameter vector to an indication representing the state of the user; determining the state of the user based upon the indication; and adjusting the voice prompt based upon the determined state of the user, wherein obtaining utterance parameters comprises: partitioning the utterance into segments; and assigning one of a plurality of classifications to each segment, each classification corresponding to at least one of a plurality of states of the user, and wherein generating the utterance parameter vector comprises: determining the number of segments for each classification; and dividing the number of segments for each classification by a total number of segments in the utterance.
12. A method of adjusting a voice prompt of a system based upon a state of a user of the system, the method comprising: receiving an utterance of the user; obtaining utterance parameters from the utterance, the utterance parameters indicating the state of the user; generating an utterance parameter vector based upon the obtained utterance parameters; converting the utterance parameter vector to an indication representing the state of the user; determining the state of the user based upon the indication; and adjusting the voice prompt based upon the determined state of the user, wherein obtaining utterance parameters comprises: partitioning the utterance into segments; and assigning one of a plurality of classifications to each segment, each classification corresponding to at least one of a plurality of states of the user, and wherein generating the utterance parameter vector comprises: determining the number of segments for each classification; and dividing the number of segments for each classification by a total number of segments in the utterance. 16. The method of claim 12 , wherein adjusting the voice prompt comprises adjusting the content of the voice prompt to use content that is consistent with the determined state of the user.