cluster analysis - Weka Xmeans: center initialization process -


in calculating xmeans clustering solution of dataset, necessary (in algorithm description) seed centers properly.

in weka xmeans, there option specify initial centers. additionally, in other xmeans libraries, user has provide initial set of centers.

however, there no indication whether or weka xmeans library create initial centers if none provided.

how weka produce initial centers if none provided? or, necessary generate initial centers in order run xmeans algorithm properly?

you cannot use predefined centers x-means.

because recursively works on subsets.

you define initial kmin (usually 2) centers. cannot predefine happen after that, , whole purpose of xmeans not have know k beforehand. if predefine k centers, do assume right k.


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