<>
See NJC`s FAQ: http://www.stata.com/support/faqs/data/panel.html
*********
clear*
set obs 20
egen float id = seq(), from(1) to(4) block(5)
egen float t = seq(), from(1) to(5) block(1)
g x=cond(runiform()<=0.5,0,1)
g byte become=.
bys id: replace become=cond(x[_n-1]==0 & x[_n]==1,1,0)
list, noo sepby(id)
***********
HTH
Martin
_______________________
----- Original Message -----
From: "Benson Limann" <[email protected]>
To: "stata" <[email protected]>
Sent: Sunday, February 08, 2009 5:46 AM
Subject: st: How to detect the change of i over t?
Hi all:
I am using an unbalanced panel dataset. i is ID and t is time. Every (i,t)
has a characteristic x=0 or 1.
I want to generate a variable called "become" such that for each (i,t):
become=1, if x=0 at time t-1, and x=1 at time t
become=0, otherwise
How to write it? My primary concern is how to deal with the first t for
each i--this observation does not have t-1.
Any suggestion would be greatly appreciated.
Ben
_________________________________________________________________
Windows Live™: E-mail. Chat. Share. Get more ways to connect.
http://windowslive.com/howitworks?ocid=TXT_TAGLM_WL_t2_allup_howitworks_022009
*
* 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/
*
* 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/