z-scores
| Command: | Tools z-scores |
Description
Allows to create a new variable containing the z-scores of the data in a numeric variable.
Required input
- Column: the column in which you want to place the z-scores numbers.
- Options
- List empty columns only: if this option is selected, only empty columns are listed in the column selection box.
- Clear column: the selected column will be cleared prior to generating and storing the z-scores.
- Header: the header (top cell) for the selected column.
- Data: select the numeric variable and a possible filter.
- Reference value and Standard Deviation
- Use mean and SD of sample: calculate the mean and Standard Deviation of the data in the sample and use the these in the calculations for the z-scores.
- User-defined values: use pre-specified values for reference value and Standard Deviation.
- Reference value: the pre-specified reference value.
- Standard Deviation: the pre-specified Standard Deviation.
Click OK to proceed. The selected column in the spreadsheet is filled with the z-scores of the selected data.
The z-score of every observation x is calculated as (x - reference value) / SD