The researcher has control of the weights of each observation.

In the help we may read:

WEIGHT Statement

WEIGHT variable ;

If you want to use relative weights for each observation in the input data set, place the weights in a variable in the data set and specify the name in a WEIGHT statement. This is often done when the variance associated with each observation is different and the values of the weight variable are proportional to the reciprocals of the variances.

The observation is used in the analysis only if the value of the WEIGHT statement variable is nonmissing and is greater than zero.

Thank you!!!!

I already sow that but I do not understand how can I put the realtive weights in the input data set if I want to obtain them.

Si conoces los pesos deberías agregarlos como una nueva variable con el nombre que quieras. Si tienes dificultades de programación en SAS, con gusto podría ayudarte. En ese caso mándame la base con los datos y la base con los ponderadores ([email protected])