Re: DM: Clustering and categorical attributes (fwd)

[Warren Sarle]

Murray Jorgensen <maj@waikato.ac.nz> wrote:
> Surely k-means clustering requires numerical attributes?

There is nothing inherently wrong with doing k-means on dummy 0|1
variables generated from categorical attributes. K-means tries to
minimize sums of squared Euclidean distances, which can be expressed
as sums of simple matching coefficients when applied to categorical
data. But whether this is a good thing to do depends on the purpose
of the analysis and the nature of the data.

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