st: frustrated by missing variables--collapase and merge

[Zhou YU <zyu@usc.edu>]

Hi all,

I have been trying to collapse merge a number of variables. What 
frustrated me is that there is always one or two variables missing after 
collapsing or merging. Last night I have to repeated the same procedures 
several times, which took me the whole evening to create a dataset. 
Intestingly, each time, different variables were missing.

Have anyone encountered the same problem? Any solutions?

Thanks a bunch!

Zhou

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