Re: st: summing across observations for given id and date

[Christian Hunkler <Hunkler@mea.uni-mannheim.de>]

Dear Anton,

the following should work:

egen x2temp = sum(x2), by(id)
bysort id: gen keep = _n
keep if keep==1
replace x2 = x2temp
drop x2temp

Best, Christian

Am 04.12.2010 18:03, schrieb Anton Granik:
> I have the following panel data set where dates sometimes repeat:
>
> id  date  x1  x2
>
> 1   t=1   1    12
> 1   t=2   1     9
> 1   t=2   2    11
> 1   t=5   1     7
>
>
> I would like to do the following:
> 1. For every individual (id) I need to add all values of x2
> corresponding to the same date, i.e. in the example above I would want
> to get rid of lines 2 and 3 and replace them with
>
> id   date   x1  x2
> 1    t=2     3   20
>
> Any easy way to do that? Thanks in advance.
>
> ---------------------
> Anton I. Granik
>
> ---------------------
> Anton I. Granik
>
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