clvalidity {chemometrics}R Documentation

compute and plot cluster validity

Description

A cluster validity measure based on within- and between-sum-of-squares is computed and plotted for the methods k-means, fuzzy c-means, and model-based clustering.

Usage

clvalidity(x, clnumb = c(2:10))

Arguments

x input data matrix
clnumb range for the desired number of clusters

Details

The validity measure for a number $k$ of clusters is $sum_j W_j$ divided by $sum_{j<l} B_{jl}$ with $W_j$ is the sum of squared distances of the objects in each cluster cluster to its center, and $B_{jl}$ is the squared distance between the cluster centers of cluster $j$ and $l$.

Value

validity vector with validity measure for the desired numbers of clusters

Author(s)

Peter Filzmoser <P.Filzmoser@tuwien.ac.at>

References

K. Varmuza and P. Filzmoser: Introduction to Multivariate Statistical Analysis in Chemometrics. CRC Press. To appear.

See Also

princomp

Examples

data(glass)
require(robustbase)
res <- pcaCV(glass,segments=4,repl=100,cex.lab=1.2,ylim=c(0,1),las=1)

[Package chemometrics version 0.4 Index]