specifies a numeric
variable whose values weight the values of the analysis variables.
The values of the variable do not have to be integers. The table below
shows what the action will be based on the weight value.
Weight Value
PROC STANDARD Action
0
Counts the observation
in the total number of observations
Less than 0
Converts the weight
value to zero and counts the observation in the total number of observations
Missing
Excludes the observation
from the calculation of mean and standard deviation
To exclude observations
that contain negative and zero weights from the calculation of mean
and standard deviation, use EXCLNPWGT. Note that most SAS/STAT procedures,
such as PROC GLM, exclude negative and zero weights by default.
Tip:When you use the WEIGHT statement, consider
which value of the VARDEF= option is appropriate. See VARDEF=divisor and the calculation
of weighted statistics in Keywords and Formulas for more information.
Details
Note: Before Version 7 of SAS,
the procedure did not exclude the observations with missing weights
from the count of observations.