The reason that
bysort panelid: drop if sum(year) ~= 12003
does not work if that -sum()- gives a
running or cumulative sum, not group sums.
This would have worked
bysort panelid : egen sumyear = total(year)
drop if sumyear != 12003
but the method recommended by Kit Baum is
greatly preferable.
Nick
[email protected]
Gregor Franz
> Great!! Thank you so much! I knew it had to be fairly obvious, I just
> couldn't figure it out.
Kit Baum
> > Gregor wrote
> > I have an unbalanced panel and would like to delete all the
> observations
> > for which I don't have the whole date range.
> >
> > year panelid x
> > 1 1 5
> > 2 1 3
> > 3 1 4
> > 1 2 7
> > 3 2 4
> >
> > In this example I would like to delete panelid 2. So that
> in the end I
> > have data for every possible year for every panelid. I
> tried to drop if
> > the sum of the years is not equal to the sum of all the 6
> years I have
> > data for (1998 to 2003), but that just left me with the
> last year of my
> > data.
> > I used bysort panelid: drop if sum(year) ~= 12003
> >
> >
> > bysort panelid: drop if _N < 6
> >
> > Remember that under a by-list _n means the current obs. and
> _N means
> > the last obs. So for an unbalanced panel, _N will be 6 for every
> > complete unit, and less than that for the ones you want to zap.
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