***** To join INSNA, visit http://www.insna.org ***** What you have explained here is the Jaccard index ( http://en.wikipedia.org/wiki/Jaccard_index), which is very closely related to the cosine similarity measure ( http://en.wikipedia.org/wiki/Cosine_similarity). Both measures are used for measuring how similar two samples (sets, clusters, etc) are. Best Aziz Abedelaziz Mohaisen Ph.D. Student, UMN http://www.cs.umn.edu/~mohaisen On Mon, Feb 21, 2011 at 9:07 PM, John McCreery <[log in to unmask]>wrote: > ***** To join INSNA, visit http://www.insna.org ***** A few months ago I > stumbled across a simple measure of cluster overlap. Assume two clusters, A > and B, that contain a total of n nodes of which m nodes belong to both > clusters or, in other words, n is the number of nodes in the union of A and > B and m the number of nodes in the intersection of A and B. The measure is > something along the lines of overlap=m/n=nodes in intersection/nodes in > union. My problem is (1) that I have forgotten where I found this measure > and (2) am not 100% sure that it was as simple as I recall. If you recognize > this problem, can point me to a source or provide me with a correct or > better formula, your help will be much appreciated. > > John > > -- > John McCreery > The Word Works, Ltd., Yokohama, JAPAN > Tel. +81-45-314-9324 > [log in to unmask] > http://www.wordworks.jp/ > _____________________________________________________________________ > SOCNET is a service of INSNA, the professional association for social > network researchers (http://www.insna.org). To unsubscribe, send an email > message to [log in to unmask] containing the line UNSUBSCRIBE SOCNET > in the body of the message. _____________________________________________________________________ SOCNET is a service of INSNA, the professional association for social network researchers (http://www.insna.org). To unsubscribe, send an email message to [log in to unmask] containing the line UNSUBSCRIBE SOCNET in the body of the message.