Re: st: replenish panel data

[Maarten Buis <maartenlbuis@gmail.com>]

On Mon, Apr 30, 2012 at 3:32 PM, "Fabian Schönenberger" wrote:
> I am facing to following problem. I have a panel data with ID=CUSIP and t=fyear and many other variables like sales, ebits etc.. I have to replenish the original data set with a new variable (inventory). Therefore I need the command to add the inventory for the equivalent CUSIP at the equivalent point-in-time. I have tried merge. But with merge also the unmatched data points are added to the origianl data set. With append I cannot specify ID and fyear.

-merge- sounds like the correct command. You need to look at the
variable _merge to determine which observations you want to keep.
Alternatively you can specify the -keep()- option. Personally, I
prefer to do the merging and dropping of redundant observations in two
separate steps.

-append- sounds wrong because this only adds new observations to your
data, while you want to add a variable to existing observations.

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany


http://www.maartenbuis.nl
--------------------------

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