how can pca be used what is uncentered data before pca prediction when to use a centered input and an uncentered input why use data as input for pca when pca is used uncentered or centered pca centered vs uncentered should pca centered input data be used what is pca based on input data when should pca data be centered first which is better pca or uncentered data what is the pca in r why is pca useful why use uncentered pca what is pca what is pca used for when is data centered what is meant by pca prediction why is pca centered for spectral data which statement is true about uncentered and centered input data? when to use uncentered and centered data for pca