

It is up to the researcher to determine if these measures are appropriate for their data. SPSS will compute those statistics if they are requested, regardless of whether or not they are meaningful. If your categorical variables are coded numerically, it is very easy to mis-use measures like the mean and standard deviation. For example, this would be the case if you had measured subjects' ages and had coded anyone between the ages of 20 and 29 as 25, or between the 30 and 39 as 35 (source: IBM SPSS Statistics Information Center). The Values are group midpoints option can be applied to certain ordinal variables that have been coded in such a way that their value takes on the midpoint of a range.


In SPSS, the Frequencies procedure can produce summary measures for categorical variables in the form of frequency tables, bar charts, or pie charts.
