roll_cor                Rolling Correlation Matrices
roll_cov                Rolling Covariance Matrices
roll_eigen              Rolling Eigenvalues and Eigenvectors
roll_lm                 Rolling Linear Models
roll_mean               Rolling Means
roll_pcr                Rolling Principal Component Regressions
roll_prod               Rolling Products
roll_scale              Rolling Scaling and Centering
roll_sd                 Rolling Standard Deviations
roll_sum                Rolling Sums
roll_var                Rolling Variances
roll_vif                Rolling Variance Inflation Factors
