Z Scores (DESCRIPTIVES command)

The z-score transformation standardizes variables to the same scale, producing new variables with a mean of 0 and a standard deviation of 1. These variables are added to the active dataset.

• To obtain z scores for all specified variables, use the SAVE subcommand.
• To obtain z scores for a subset of variables, name the new variable in parentheses following the source variable on the VARIABLES subcommand and do not use the SAVE subcommand.
• Specify new names individually; a list in parentheses is not recognized.
• The new variable name can be any acceptable variable name that is not already part of the active dataset. For information on variable naming rules, see “Variable Names” on p. 36.

Example

DESCRIPTIVES VARIABLES=NTCSAL NTCPUR (PURCHZ) NTCPRI (PRICEZ). 

• DESCRIPTIVES creates z-score variables named PURCHZ and PRICEZ for NTCPUR and NTCPRI, respectively. No z-score variable is created for NTCSAL.