Dear all,
I have a dataset with 200'000 observations, and a lot of observation have the same ID. I want to keep only 1 observation of each ID, lets say the first one that have this particular ID.
My dataset is like this:
ID variable Z
1 45.6
1 46.7
1 47.8
1 .
2 .
2
2
3
4
5
5
5
5
An I want to transform the dataset like this:
1 45.6
2
3
4
Does anyone has the magic command for that???
Laura
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