storing information from merging

[Zariab Hossain]

Hi Stata users,

I am working with merging datasets in a loop (meaning at least hundreds of merging). However, I need to save the value of unmatched observations as a new variable. Is it possible to do it in Stata?

For example, after the merging I want to create a variable and store 983, 770 and so on as its values.

Any help would be highly appreciated.

Best,
Zariab Hossain
Uppsala University

[Clyde Schechter]

Well, unless you have specified the -nogenerate- option in your -merge- command (in which case, you should remove it) -merge- automatically creates this for you. Your data set has a new variable called _merge which takes on the value 1 for master only, 2 for using only, and 3 for matched. If you need to access the total number in each group you can do -tab _merge- to see it in the Results window. Or if you need another variable that gives those counts:

by _merge, sort: gen `c(obs_t)' wanted = _N

[Zariab Hossain]

Dear Clyde

Thanks a lot for your suggestion. It worked.