15. A method for combining multiple clusterings from a plurality of membership matrices into a consensus clustering and correspondence matrices, comprising: iteratively computing the consensus clustering and correspondence matrices with an automated processor, from the plurality of membership matrices by minimization of an objective function comprising at least an consensus function, a term to enforce a column sparseness constraint, and a term to enforce a matrix row sum constraint, until predetermined convergence conditions are achieved, until predetermined convergence conditions are satisfied; and storing the computed consensus clustering and the correspondence matrices in a memory.
20. The method according to claim 15 , wherein the membership matrices comprise clusterings of content anchor text, uniform resource locators (URLs), and hyperlinks of hyperlinked documents.