[R] K-평균 클러스터링 분석 수행

K-Means Clustering : 주어진 데이터를 k개의 클러스터로 묶는 알고리즘

iris2=iris[1:4]

head(iris2)

km.out.withness=c()
km.out.between=c()

for(i in 2:7){
  set.seed(1)
  km.out=kmeans(iris2,center=i)
  km.out.withness[i-1]<-km.out$tot.withinss
  km.out.between[i-1]<-km.out$betweenss
}
data.frame(km.out.withness, km.out.between)

km.out.k3=kmeans(iris2,centers = 3)
km.out.k3$centers

km.out$cluster

km.out.k3$size

table(km.out.k3$cluster,iris$Species)

plot(iris2[,1:2],
     col=km.out.k3$cluster,
     pch=ifelse(km.out.k3$cluster==1,16,
                ifelse(km.out.k3$cluster==2,17,18)),
     cex=2)

points(km.out.k3$centers,
       col=1:3,
       pch=16:18,
       cex=5)