Ordinal scale variables differ from nominal scale data because the groups have a predefined order. If numeric codes are used to represent the groups, the order is inferred from the ascending value of the numeric codes. When group names are used the order must be manually set, by mapping group names to numeric codes. The groups will then be ordered based on the ascending value of the numeric codes.
For nominal scale variables the numeric codes can be used to change how the groups are presented, from the default alphabetical name order, on output .
To set the mapping between group names and codes:
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