Calculating Weighted Statistics

By default, each observation is counted only once in the calculation of the chart statistics. To calculate weighted statistics in which an observation can be counted more than once, use the FREQ= option. This option identifies a variable whose values are used as a multiplier for the observation in the calculation of the statistic. If the value of the FREQ= variable is missing, 0, or negative, the observation is excluded from the calculation.
If you use the SUMVAR= option, then for each observation, the value of the SUMVAR= variable is multiplied by the value of the FREQ= variable in calculating the chart statistic.
For example, to use a variable called COUNT to produce weighted statistics, assign FREQ=COUNT. If you also assign the variable HEIGHT to the SUMVAR= option, then the following table shows how the values of COUNT and HEIGHT would affect the statistic calculation:
Value of COUNT
Value of HEIGHT
Number of Times the Observation is Used
Value Used for HEIGHT
1
55
1
55
5
65
5
325
.
63
0
-
-3
60
0
-