On Tue, 2 Oct 2012 14:32:12 -0400 John Sorkin
<jsor...@grecc.umaryland.edu> wrote:

> Ranjan,
> Thank you for your help. What eludes me is how one computes the distance from 
> each cluster for each subject. For my first subject, datascaled[1,], I have 
> tried to use the following: 
> v1 <- sum(fit$centers[1,]*datascaled[1,])
> v2 <- sum(fit$centers[2,]*datascaled[1,])
> v3 <- sum(fit$centers[2,]*datascaled[1,])
> hoping the max(v1,v2,v3) would reproduce the group assignment, i.e. simply 
> assign the subject to the group that gives the largest value, but it does 
> not. How is the distance to the three clusters computed for each subject?
> Thanks,
> John 

Well, it should be:

v <- vector(length = 3)
for (i in 1:3) 
   v[i] <- sum((fit$centers[i, ] - datascaled[1, ])^2)

whichmin(v)

should provide the cluster assignment.

Btw, there is a better, more efficient and automated way to do this,
i.e. avoid the loop using matrices and arrays and apply, but I have not
bothered with that here. 

Ranjan

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