Re: st: Re: how to search every observation of one variable in another variable

["Joseph Coveney" <stajc2@gmail.com>]

ibrahim bostan wrote:

the code you gave did not work because citing patent no is not unique
identifier, can it be fixed?

it gave this error;
"variable citing_pt_no does not uniquely identify observations in the
using data"

 
--------------------------------------------------------------------------------

I assume that you're referring to the result of the -isid- command.  Put the
following just before it:

    contract citing_pt_no patent_owner

and then proceed with -isid-.

As  Sergiy Radyakin shows later in the thread, you don't need to decompose the
dataset into the two components and then reconstruct it.  You can just
-merge-the one back into the original dataset.  Unless you're confident that
there aren't any errors in the dataset (such as a citing patent's having one
owner early in the dataset and by accident having another owner later on in the
dataset), I recommend applying the constraints and checks (-contract-, -isid-,
-merge 1:... assert()-, etc.) that I showed.

Also, unless your dataset has a dummy entry of each cited patent's citing itself
in order to assure that every cited patent has an owner, you might want to
consider setting the indicator variable to .u (for "Unknown") for observations
where the cited-patent owners are "Other" (my code; probably would have been
better as "Unknown" and not "Other") or blank (Sergiy's code).  That way you can
keep track of citing patents where your dataset doesn't really allow you to say
whether the owner owns the cited patent.

Joseph Coveney

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