My simple problem is that when i run kmeans this give me different results because if centers is a number, a random set of (distinct) rows in x is chosen as the initial centres.
About me the problem is simple. The question i ask you is if it possible that centers could be different from number. i.e. instead of indicate a number of center, could be possible indicate different character lable to identify the cluster i want to obtain? thk you 2007/3/29, Gavin Simpson <[EMAIL PROTECTED]>: > > On Thu, 2007-03-29 at 15:02 +0200, Sergio Della Franca wrote: > > Dear R-Helpers, > > > > I read in the R documentation, about kmeans: > > > > centers > > > > Either the number of clusters or a set of initial (distinct) cluster > > centres. *If a number*, a random set of (distinct) rows in x is chosen > as > > the initial centres. > > My question is: could it be possible that the centers are character and > not > > number? > > I think you misunderstand - centers is the number of clusters you want > to partition your data into. How else would you specify the number of > clusters other than by a number? So no, it has to be a numeric number. > > The alternative use of centers is to provide known starting points for > the algorithm, such as from the results of a hierarchical cluster > analysis, that are the locations of the cluster centroids, for each > cluster, on each of the feature variables. > > Also, argument x to kmeans() is specific about requiring a numeric > matrix (or something coercible to one), so characters here are not > allowed either. > > But then again, I may not have understood what it is that you are > asking, but that is not surprising given that you have not provided an > example of what you are trying to do, and how you tried to do it but > failed. > > > and provide commented, minimal, self-contained, reproducible code. > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > G > -- > %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% > Gavin Simpson [t] +44 (0)20 7679 0522 > ECRC, UCL Geography, [f] +44 (0)20 7679 0565 > Pearson Building, [e] gavin.simpsonATNOSPAMucl.ac.uk > Gower Street, London [w] http://www.ucl.ac.uk/~ucfagls/ > UK. WC1E 6BT. [w] http://www.freshwaters.org.uk > %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% > > [[alternative HTML version deleted]] ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
