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		zmmmmm on Oct 5, 2019 \| parent \| context \| favorite \| on: Principal Component Analysis Am I missing something or is equation (9) incorrect unless the mean of the random variable x is zero (which is never specified)?

clircle on Oct 6, 2019 [–]

You are correct, eqn 9 is technically wrong. But it is traditional in PCA to de-mean the columns of X.

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