Define Column Range in Correspondence Analysis
You must define a range for the column variable. The minimum and maximum values specified must be integers. Fractional data values are truncated in the analysis. A category value that is outside of the specified range is ignored in the analysis.
All categories are initially unconstrained and active. You can constrain column categories to equal other column categories, or you can define a column category as supplementary.
- Categories must be equal. Categories must have equal scores. Use equality constraints if the obtained order for the categories is undesirable or counterintuitive. The maximum number of column categories that can be constrained to be equal is the total number of active column categories minus 1. To impose different equality constraints on sets of categories, use syntax. For example, use syntax to constrain categories 1 and 2 to be equal and categories 3 and 4 to be equal.
- Category is supplemental. Supplementary categories do not influence the analysis but are represented in the space defined by the active categories. Supplementary categories play no role in defining the dimensions. The maximum number of supplementary column categories is the total number of column categories minus 2.
To Define a Column Range in Correspondence Analysis
- Select the column variable in the Correspondence Analysis dialog box.
- Click Define Range.
- Enter the minimum and maximum values for the column variable.
- Click Update.
- Click Continue.
Optionally, you can specify equality constraints on the column variable categories and define categories to be supplementary. For each category to be constrained or supplementary, select the category from the list of categories generated by Update and choose Category is supplemental or Categories must be equal. For equality constraints, at least two categories must be designated as equal.