11. The apparatus of claim 10 , wherein when the apparatus determines which ones of the plurality of utterances are most informative for labeling, the apparatus is configured to: determine a confidence score with respect to each of the predicted labels of the plurality of utterances by using the existing classification model; and determine the ones of the plurality of utterances that are most informative for labeling by determining ones of the plurality of utterances that have the lowest determined confidence scores.
10. The apparatus of claim 7 , wherein the apparatus is further configured to: predict labels of a plurality of utterances for the target application by using the existing classification model; determine which ones of the plurality of utterances are most informative for labeling; and present, to a labeler, the determined ones of the plurality of utterances for labeling.