Here is my problem. I need to drop *permanently* observations. The command smpl (--restrict) simply creates a sub sample but it does not change the dataset range. This causes the full range to reappear each time I use smpl --full in the loops. And I cannot save a restricted version of the dataset and then reopen it cause I loose the session (in particular matrices, vectors and scalars). Is there a way to really drop observations? I need the "reverse" of addobs. Thanks Giuseppe