Re: a principal component analysis question

Yiyu wrote:
> No, the 2 groups can not be identified before the PCA was run.
> Actually I hope to identify the 2 groups using the information
> from the PCA. What's more, even the number of groups can't be known
> before hand. ( K can > 1000 and number of meaningful principal
> component can be > 5).

Any collection of individuals (people?) whose scores on a component
are approximately the same will appear to be a "group" in which that
component explains little variation. There are likely to be many such
"groups".

.

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