pca                     Principal Component Analysis (Custom Scree
                        Style)
pcreg                   Principal Component Regression (PCR)
robust_pca              Robust Principal Component Analysis (Robust
                        PCA)
robust_pcreg            Robust Principal Component Regression (Robust
                        PCR)
sparse_pca              Sparse Principal Component Analysis (Sparse
                        PCA)
sparse_pcreg            Sparse Principal Component Regression (Sparse
                        PCR)
supervised_pca          Supervised Principal Component Analysis (SPCA)
supervised_pcreg        Supervised Principal Component Regression
