13. The call center device of claim 6 wherein: the training device is further configured to classify each path variation in the word lattices as a slot, a paraphrase, or neither; and during the instantiating of the chosen at least one word lattice, the utterance generation component is configured to substitute data provided by the dialog manager for any slot path variation and to choose one path of any paraphrase path variation based on weights of the paths of the paraphrase path variation.
6. The call center device of claim 1 further comprising: a training device comprising at least one computer configured to construct the set of word lattices from training dialogs between call center agents and second parties and to assign to the word lattices τ the conditional probabilities p(τ|DA type) over dialog act types DA type.