RESCALE Subcommand (KNN command)

The RESCALE subcommand is used to rescale covariates.

All rescaling is performed based on the training data, even if a holdout sample is defined (see PARTITION Subcommand (KNN command)). That is, the minimum value or maximum value of a covariate are computed using only the training data. It is important that these covariates have similar distributions across the training and holdout samples. If the data are partitioned by specifying ratios on the PARTITION subcommand, then the KNN procedure attempts to ensure this similarity by random assignment. However, if you use the PARTITION subcommand VARIABLE keyword to assign cases to the training and holdout samples, then we recommend that you confirm the distributions are similar across samples before running the KNN procedure.

COVARIATE Keyword

The COVARIATE keyword specifies the rescaling method to use for covariates specified following WITH on the command line. If no covariates are specified on the command line, then the COVARIATE keyword is ignored.

ADJNORMALIZED. Adjusted version of subtract the minimum and divide by the range, [2*(x−min)/(max−min)]−1.

NONE. No rescaling of covariates.