On Wed, 24 Feb 2010, Caro Landry wrote:
I haven't found any answer to this problem online, and so am
someone can help me here.
I need to:
a) create a new series that comprises only the positive observation of a
b) only use the observations for which the new series are not equal to 0 in
If the series is called "y":
smpl y > 0 --restrict