2. The computer-implemented method of claim 1 , wherein the phase transition method comprises f/N x , where f is a measure of frequency of a respective keyword in a respective one of the Web documents, N is a number of Web documents that include the respective keyword and x is greater than or equal to 1.
2. The computer-implemented method of claim 1 , wherein the phase transition method comprises f/N x , where f is a measure of frequency of a respective keyword in a respective one of the Web documents, N is a number of Web documents that include the respective keyword and x is greater than or equal to 1. 3. The computer-implemented method of claim 2 , wherein the keywords are extracted from harvested Web documents, in part, using stop word removal.