Dear community,

I have a somewhat tricky problem: I grouped several observations together according to their postal code. Some of the data tuples have an additional dummy variable equal to 1, while others do not. Essentially, I want to drop all the groups (yes, the entire group) where there is no a single individual with this additional dummy variable being equal to 1. Do you think that this is possible to implement with STATA?

Thank you a lot!!

Marie