1. A computer-implemented method in a dialog system, comprising: receiving a user utterance including a proper name; recognizing the proper name in the user utterance; determining a first confidence score for the recognized proper name; generating a first machine response the user utterance including an indirect confirmation question related to the proper name, wherein the first machine response does not repeat the proper name, if the first confidence score is below a defined threshold value; receiving a user response to the indirect confirmation question; and modifying the first confidence score to generate a second confidence score based on the user response.