You can use the Roles tab to specify a frequency variable or weight variable for the analysis.
A frequency variable is a numeric variable whose value represents the frequency of the observation. If you use a frequency
            variable, the underlying procedure assumes that each observation represents  observations, where
 observations, where  is the value of the frequency variable.
 is the value of the frequency variable. 
         
A weight variable is a numeric variable with values that are relative weights for the analysis.