18. The product according to claim 13 , wherein clustering algorithm is an iterative clustering algorithm.
13. A computer program product encoded in a non-transitory computer-readable medium for automatic unsupervised clustering of dialog data from a natural language dialog application, the product comprising: program code for automatically generalizing structured dialog data extracted from application logs using different independent generalization methods to produce generalization identifier vectors aggregating the results of the methods used, the structured dialog data including a transcription of a dialog between a user and the natural language dialog application, the transcription being generated by the natural language dialog application, the generalization identifier vectors indicating descriptive categories of the different independent generalization methods that correspond to statements by the user and statements by the natural language dialog application included in the extracted dialog data; and program code for automatically clustering the dialog data based on the generalization identifier vectors using an unsupervised density-based clustering algorithm without a predefined number of clusters and without a predefined distance threshold.