[ /MEDIAN [(value)] = var_list BY variable (value1, value2) ]
The median test is used to test whether independent samples come from
populations with a common median.
The median of the populations against which the samples are to be tested
may be given in parentheses immediately after the
/MEDIAN subcommand. If it is not given, the median is imputed from the
union of all the samples.
The variables of the samples to be tested should immediately follow the ‘=’ sign. The
keyword BY must come next, and then the grouping variable. Two values
in parentheses should follow. If the first value is greater than the second,
then a 2 sample test is performed using these two values to determine the groups.
If however, the first variable is less than the second, then a k sample test is
conducted and the group values used are all values encountered which lie in the
range [value1,value2].