Weighted standard deviation

[#1]

Hi everybody,

I really need help in Set analysis for calculating weighted standard deviation.

The regular standard deviation formula is here:

Stdev({$<X.QID = {$(=only(X_LIST.QID))}, Y.QID = {$(=only(Y_LIST.QID))}, %RESPONDENT = {">0"}>} Y.Answer)

To calculate the weighted one I need to have a formula like:

SQRT(Sum({$<X.QID = {$(=only(X_LIST.QID))}, Y.QID = {$(=only(Y_LIST.QID))}, %RESPONDENT = {">0"}>} SQR(WEIGHT*Y.Answer-MEANW))/

Count(({$<X.QID = {$(=only(X_LIST.QID))}, Y.QID = {$(=only(Y_LIST.QID))}, %RESPONDENT = {">0"}>}  Y.Answer))

The MEANW - weighted average that was calculated before, but I don't know how to implement it into the set analysis. And if I calculate the MEANW in the STDEV  formula, I don't get any results.

Please help!

Thank you very much in advance!

[#2]

Have you tried using the object Statistics Box?

[#3]

Thank you for your reply. Unfortunately, I did not find a way to use the Statistics Box in my case (couldn't set expressions in there).