Yes, Nick has it. If the width() option is not wide enough -xtdes- will report
non-unique id*time values (example below).
What is the purpose of the width() option?
Scott
. webuse grunfeld
. xtdes, width(3)
company: 1, 2, ..., 10 n = 10
year: 1935, 1936, ..., 1954 T = 20
Delta(year) = 9; int((1954-1935)/9) + 1 = 3
(company*year does not uniquely identify observations)
. xtdes
company: 1, 2, ..., 10 n = 10
year: 1935, 1936, ..., 1954 T = 20
Delta(year) = 1; (1954-1935)+1 = 20
(company*year uniquely identifies each observation)
----- Original Message -----
From: Nick Cox <[email protected]>
Date: Wednesday, August 4, 2004 12:48 pm
Subject: RE: st: Again-Unique Case ID in Large Panel
> I got it, I think. You need to play
> around with the -width()- option in
> -xtdes-. I surmise that the default
> is not big enough for your data.
>
> (I was predisposed to think the blame
> would lie with -xtdes-.)
>
> Nick
> [email protected]
>
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