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Topic: How to calculate variance explained by clusters (multid)?
Replies: 0

 neuronet Posts: 24 Registered: 10/18/12
How to calculate variance explained by clusters (multid)?
Posted: Nov 1, 2012 11:13 PM

I want to calculate the variance explained by clusters. For univariate data, it is easy:
between-group variance / total variance.

But what about for multivariate data? Can I just use the same equations as for between-group SS and degree of freedom, but replace (xi-xj)^2 terms with d(xi,xj)^2 terms?

So for instance, in univariate the numerator of the total variance would be:
sum[(xi-xmean)^2]
For the total variance of my multivariate data can I just use:
sum[d(xi-xmean)^2] ?

Or is there more to it than that? Can anyone recommend a succinct description of this that actually gives equations?