15. The system of claim 10 , the at least two similarity analysis modules further configured to generate the similarity score information by generating a first pseudo-document similarity score for the individual candidate strings which describes a strength of relatedness of the individual candidate strings to the entity reference string, and a second pseudo-document similarity score for the individual candidate strings which describes a strength of relatedness of the entity reference string to the individual candidate strings.
17. The system of claim 15 , wherein said generating the first pseudo-document similarity score for the individual candidate strings comprises: receiving a set of pseudo-documents, an individual pseudo-document in the set of pseudo-documents corresponding to a respective document in the set of documents, and the individual pseudo-document containing a set of terms found in queries that have been submitted and which have resulted in the selection of the respective document; determining, for the individual candidate strings, a number of pseudo-documents that contain all of the terms of the set in the individual candidate strings; and generating the first pseudo-document similarity score for the individual candidate strings using said number.