Method and apparatus for clustering a collection of linked documents using co-citation analysis

A system for clustering documents in a collection of linked documents, said system comprising

• means for accessing said documents in said collection of linked documents;
• means for specifying a link frequency threshold;
• link analysis means for analyzing the links contained in said documents in said collection of linked documents, said link analysis means further comprising:
• means for determining the number of times a document has been linked to;
• and
• means for generating a co-citation list, said co-citation list indicating pairs of documents that have been linked to by the same document;
• clustering means for generating document clusters from said co-citation list.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for the clustering of documents in a collection of linked documents, said method steps comprising:

• a) specifying a link frequency threshold, said link frequency threshold indicating a number of times a document is linked to from another document in said collection;
• b) for each document in said collection, determining an associated link frequency;
• c) discarding each document in said collection whose link frequency is lower than said link frequency threshold;
• d) creating a co-citation list, said co-citation list comprised of pairs of documents that are linked to by the same document in said collection;
• and
• e) performing a suitable clustering operation on said co-citation list to generate document clusters.