Define Range and Scale
You must define a range for each variable. The maximum value that is specified must be an integer. Fractional data values are truncated in the analysis. A category value that is outside of the specified range is ignored in the analysis. To minimize output, use the Automatic Recode facility (available from the Transform menu) to create consecutive categories beginning with 1 for variables that are treated as nominal or ordinal. Recoding to consecutive integers is not recommended for variables that are scaled at the numerical level. To minimize output for variables that are treated as numerical, for each variable, subtract the minimum value from every value and add 1.
You must also select the scaling to be used to quantify each variable.
- Ordinal. The order of the categories of the observed variable is preserved in the quantified variable.
- Single nominal. In the quantified variable, objects in the same category receive the same score.
- Multiple nominal. The quantifications can be different for each dimension.
- Discrete numeric. Categories are treated as ordered and equally spaced. The differences between category numbers and the order of the categories of the observed variable are preserved in the quantified variable.