how does data pca work? how variables are used to calculate pca how is the data used for pca how do we understand the magnitude of variables in a pca how do you figure the magnitudes of variables in a pca what's the purpose of a pca how to calculate pca what variables are included in pca how do you calculate pca what is the importance of the magnitude of a pca why do you use principal component analysis when you are comparing three dimensions of a period what is the purpose of a pca? what is the difference between a principal component and a variable magnitude? do the magnitudes affect pca what's the relationship between the variables? eigenvectors pca definition how do i do a parametric analysis for an individual variable what is the definition of pca data what is the purpose of pca analysis does the magnitude of the data affect the output of pca?