Bookmark and Share

Notice: On March 31, it was announced that Statalist is moving from an email list to a forum. The old list will shut down at the end of May, and its replacement, statalist.org is already up and running.


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

st: Identifying first observation in each panel of unbalanced panel


From   Ivan Png <iplpng@gmail.com>
To   statalist@hsphsun2.harvard.edu
Subject   st: Identifying first observation in each panel of unbalanced panel
Date   Mon, 4 Jun 2012 13:13:15 -0400

I am analyzing an unbalanced panel of company data, organized by
company (gvkey) and year.  I want to create  a flag to the first
observation of each company in the panel.  I tried

 . sort gvkey year
 . by gvkey , sort: gen flag = 1 if  _n == 1

However, this only flagged flag = 1 if a company was present in year 1
of the panel.  It missed any company that appeared in later years.

I searched statalist and found this:
http://www.stata.com/statalist/archive/2005-04/msg00334.html

But it doesn't work.  I'd be grateful for any relevant help.
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/


© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   Site index