Hi All,

I am running a regression model in STATA. The regression equation is as following:

y=a+b1*X1+b2*X2+b3*X3+...

In my case, it makes no sense to impute missing values for one variable X3 because missings in this variable are logical skipping. However, I don't want the missings in X3 to reduce the sample size when I estimate b1 & b2. Does anyone know how I can let STATA know it should use a different sample size when estimating b1,b2, and b3?

Your input will be greatly appreciated!