Hi folks, Just a quick jump-in:
k-means needs a distance matrix, but it's k x n in size. You can also partition the computation if you had extremely large n, but in general, if n is very large, then you can typically uniformly subsample (note: imho, the user should decide on if/how to subsample), and produce approximately the same clustering results. Duane On Wed, Mar 9, 2011 at 9:21 AM, John Darrington <j...@darrington.wattle.id.au> wrote: > Hi Mehmet! > > As I mentioned, the CLUSTER command is soemthing which I think it would be > great to support. > > One issue with clustering is its memory complexity. It requires O(n^2) where > n is the number of cases being clustered. > Have you tested your algorithm with large numbers of cases? > > Maybe Ben has some ideas how an efficient distance matrix can be implemented > in PSPP (maybe sparse-array.c can help?) . > > In any case, I'd be interested to see your code, and the results of your > comparisons. Can you post them somewhere? > > > J' > > On Tue, Mar 08, 2011 at 05:56:37AM -0800, Mehmet Hakan Satman wrote: > hi everybody, > > I am interested in PSPP and i read about something about the needs for > developing some functionality. > I implemented a k-means clustering library using the GNU scientific > library and > sent an informative e-mail to John. He suggested me to join this group > and share > my ideas with the stuff. > > > I compared the results with SPSS outputs. The analysis of variance table > is not > completed but we may add this feature. > > I would be glad to integrate something to PSPP and work with you. > > What do you think about this? > > > > -- > PGP Public key ID: 1024D/2DE827B3 > fingerprint = 8797 A26D 0854 2EAB 0285 A290 8A67 719C 2DE8 27B3 > See http://pgp.mit.edu or any PGP keyserver for public key. > > > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.9 (GNU/Linux) > > iD8DBQFNd373imdxnC3oJ7MRAiGaAJ4/dtjbbV3KdVan3GHn8X/WdH55sACdF81A > AxfQCcqJVTLssK99rx3txVg= > =rRIN > -----END PGP SIGNATURE----- > > _______________________________________________ > pspp-dev mailing list > pspp-dev@gnu.org > http://lists.gnu.org/mailman/listinfo/pspp-dev > > _______________________________________________ pspp-dev mailing list pspp-dev@gnu.org http://lists.gnu.org/mailman/listinfo/pspp-dev
