What is the difference between PCA-none scaling and PCA-Unit variance-center?

06 June 2014 1 3K Report

I am going to compare two groups of bacteria based on their metabolites.

PCA; Principle Component Analysis

See the attachment for a definition of centered unit variance predictors. Re-scaling the predictors to unit variance is typically performed during principal components regression.

The Elements of Statistical Learning provides a brief description of PCA and PCR and is freely available online from:

http://statweb.stanford.edu/~tibs/ElemStatLearn/

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