Hi Sarah, Thank you for the response. But it is said in its description that after each run (sample), each observation in the whole dataset is assigned to the closest cluster. So how is it possible for one observation to be wrongly allocated, even with clara?
Behnam Behnam On Fri, Feb 19, 2016 at 11:48 AM -0800, "Sarah Goslee" <sarah.gos...@gmail.com<mailto:sarah.gos...@gmail.com>> wrote: That means that points have been assigned to the wrong groups. This may readily happen with a clustering method like cluster::clara() that uses a subset of the data to cluster a dataset too large to analyze as a unit. Negative silhouette numbers strongly suggest that your clustering parameters should be changed. Sarah On Fri, Feb 19, 2016 at 6:33 AM, ABABAEI, Behnam <behnam.abab...@limagrain.com> wrote: > Hi, > > > We know that clustering methods in R assign observations to the closest > medoids. Hence, it is supposed to be the closest cluster each observation can > have. So, I wonder how it is possible to have negative values of silhouette , > while we are supposedly assign each observation to the closest cluster and > the formula in silhouette method cannot get negative? > > > Behnam. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.