Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: st: How to generate dummy for the following years
From
umut senalp <[email protected]>
To
<[email protected]>
Subject
RE: st: How to generate dummy for the following years
Date
Fri, 27 Jul 2012 13:14:53 +0300
Dear Ronnie,
Thank you for your reply, as you said, the code you provided has generated "always_exporter" successfully.
Regarding to your latest reply:
generate starter == .
replace starter == 1 if export2003 == 0 & export2004 == 1
I do not think that I will be able to capture all "starters" with this way practically, since some firms start to export 2005 some of them 2007 etc. So I need to write a code to find the first export dummy taking the value of "1" for each firm, it will show me that the firm switch from 0 to 1 first time (means it start to export). I tried to show what I am trying to do with an example below. Thanks again,
Best
Umut
firm id year export starter
> 1 2003 0 0
> 1 2004 0 0
> 1 2005 0 0
> 1 2006 1 1
> 1 2007 0 0
> 1 2008 1 0
> 1 2009 1 0
> 1 2010 1 0
> 1 2011 1 0
> 2 2003 0 0
> 2 2004 0 0
> 2 2005 0 0
> 2 2006 0 0
> 2 2007 1 1
> 2 2008 0 0
> 2 2009 0 0
> 2 2010 0 0
> 3 2003 0 0
> 3 2004 1 1
> 3 2005 1 0
> 3 2006 0 0
> 3 2007 0 0
> 3 2008 0 0
> 3 2009 0 0
> 3 2010 0 0
> 3 2011 1 0
> 4 2010 0 0
> 4 2011 1 1
----------------------------------------
> Date: Fri, 27 Jul 2012 08:42:03 +0300
> From: [email protected]
> To: [email protected]
> Subject: Re: st: How to generate dummy for the following years
>
> Umut
> Reading through your email again, I don't think I answered your question so the only useful part of my earlier response may be how to generate always_exporter.
>
> Ps: For what you were trying to do with
>
> **
> gen starter=0
> replace starter=1 if export==0 in 2003 & export==1 in 2004
>
> ***
>
> I am wondering if what you are looking for is a -reshape-, so
>
> reshape wide export, i(firm_id) j(year)
>
> This would give you
>
> firm_id export2003 export2004 export2005 export2006 export2007 export2008 export2009 export2010 export2011
> 00028073 1 1 0 1 0 1 1 1 1
> 00036721 0 0 0 0 0 0 0 0 .
> 00047152 1 1 1 0 0 0 0 0 1
> 00063351 . . . . . . . 1 1
> 00144277 . . . . 1 1 0 1 .
> 00144614 . . . . . . 0 0 .
> 00145362 1 1 1 . . . . . .
> 00147034 1 1 1 1 1 1 1 1 .
>
> You can then
> generate starter == .
> replace starter == 1 if export2003 == 0 & export2004 == 1
>
> Or, to create a dummy, you can
> gen starter = export2003 == 0 & export2004 == 1
>
> Ronnie
> --
>
>
> 010100100110111101101110011011100110100101100101
>
>
>
>
> On Friday, July 27, 2012 at 12:28 AM, Ronnie Babigumira wrote:
>
> > Umut,
> > Regarding your original question on generating dummies. There will be more direct ways but here is one way to do it.
> >
> > clear
> > input str8 firm_id year export
> > 00028073 2003 1
> > 00028073 2004 1
> > 00028073 2005 0
> > 00028073 2006 1
> > 00028073 2007 0
> > 00028073 2008 1
> > 00028073 2009 1
> > 00028073 2010 1
> > 00028073 2011 1
> > 00036721 2003 0
> > 00036721 2004 0
> > 00036721 2005 0
> > 00036721 2006 0
> > 00036721 2007 0
> > 00036721 2008 0
> > 00036721 2009 0
> > 00036721 2010 0
> > 00047152 2003 1
> > 00047152 2004 1
> > 00047152 2005 1
> > 00047152 2006 0
> > 00047152 2007 0
> > 00047152 2008 0
> > 00047152 2009 0
> > 00047152 2010 0
> > 00047152 2011 1
> > 00063351 2010 1
> > 00063351 2011 1
> > 00144277 2007 1
> > 00144277 2008 1
> > 00144277 2009 0
> > 00144277 2010 1
> > 00144614 2009 0
> > 00144614 2010 0
> > 00145362 2003 1
> > 00145362 2004 1
> > 00145362 2005 1
> > 00147034 2003 1
> > 00147034 2004 1
> > 00147034 2005 1
> > 00147034 2006 1
> > 00147034 2007 1
> > 00147034 2008 1
> > 00147034 2009 1
> > 00147034 2010 1
> > end
> >
> > * Always exporter
> > tempvar foo
> > bys firm_id : egen `foo' = mean(export)
> > gen always_exporter = `foo' == 1
> >
> > * Start and end data for exporters
> > * Split data
> > tempfile fdata nedata
> > save `fdata'
> > drop if export == 1
> > save `nedata'
> > use `fdata'
> > keep if export == 1
> >
> > bysort firm_id (year): gen start= year[1]
> > bysort firm_id (year): gen end= year[_N]
> >
> > * Append non-export data and fillin missing data
> > append using `nedata'
> > bys firm_id (start): replace start = start[_n-1] if start >= .
> > bys firm_id (end): replace end = end[_n-1] if end >= .
> >
> > sort firm_id year
> > list, sepby(firm_id)
> >
> >
> >
> > Hope this is helpful
> >
> > Ronnie
> >
> > --
> > 010100100110111101101110011011100110100101100101
> >
> >
> >
> >
> > On Thursday, July 26, 2012 at 6:07 PM, umut senalp wrote:
> >
> > > Dear Stata Listers,
> > >
> > > I am using StataSE 12. I have an unbalanced data for over 2000 firms (covering the period 2003-2011) and I have a dummy variable for the firms' export status (Export=1 if firm have positive export value that year). While, a few firms observed for all 9 years (2003-2011), majority of them observed for minimum 2 years consecutively.
> > > I want to create a new set of dummy variables indicating the year that a firm started to export (Starter),
> > > one year before starting to export (Year_before),and for the following two years that the firm started to export which are Year_After and Two_Years_After.
> > > So, I want to generate 4 new dummies based on the firm's Export status. In addition to that, I have some firms which are exporter for the all period that they are observable (means I do not know when they started to export), and I want to name them as Always_Exporter.
> > >
> > > Since I am not so familiar with programming in Stata I tried following command but it failed, it was just for the firms that I have observation for 2003 onwards, anyway.
> > > gen starter=0
> > > replace starter=1 if export==0 in 2003 & export==1 in 2004
> > >
> > > And I realised that this approach will not work since I need to do it for many times for following years to catch all starters.
> > >
> > > Well, I think I need to use a program that includes loop but I don't know where to start to write the code. I would be glad if you could help me on this issue. I hope I've the issue clear enough.
> > >
> > > Kind regards
> > >
> > > Umut SENALP
> > > *
> > > * 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/
*
* 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/