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Re: st: RE: Specification for a 1/0 variable with consecutive non-missing observations


From   Alejandro Delafuente <alejandro.delafuente@st-antonys.oxford.ac.uk>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: RE: Specification for a 1/0 variable with consecutive non-missing observations
Date   Fri, 10 Jun 2005 18:15:58 +0100 (BST)

Thanks David. After having a look at your program I think it should work, but 
actually my 40 variables are months followed by year (ie, jan1990 feb1990, ..., 
may1993) and am still figuring out how to number them. Can you see anything 
wrong if using a sequenced variable (x) I do the following:

foreach var of varlist jan1990-may1993 {
rename `var' `var'x[_n]
}


In message <97D60F3695FA1A4E82535413AB0914A7375457@icnarc-app.icnarc.org> 
statalist@hsphsun2.harvard.edu writes:
> Assuming your 40 variables are consecutively numbered in some way (here I 
have assumed var1-var40), the following (untested) code should be about right...
> 
> gen cons=0
> gen maxcons=0
> forvalues i=1/40 {
> 	replace cons=cons+1 if !missing(var`i')
> 	replace cons=0 if missing(var`i')
> 	replace maxcons=cons if cons>maxcons
> }
> gen byte cons20=maxcons>=20
> 
> The final variable (cons20) is the 1/0 variable you are after (maxcons will 
contain the longest run of consecutive non-missing variables).
> 
> Hope this helps
> 
> David
> 
> -----Original Message-----
> From: Alejandro Delafuente
> [mailto:alejandro.delafuente@st-antonys.oxford.ac.uk]
> Sent: 10 June 2005 16:23
> To: statalist@hsphsun2.harvard.edu
> Subject: st: Specification for a 1/0 variable with consecutive
> non-missing observations
> 
> 
> Hi statalisters,
> I have a time series for 40 years (40 continuos variables) and am trying to 
> create a 1/0 variable that indicates 1 (for each row) if at least 20 
variables 
> in the series have consecutive non-missing values and 0 if this condition is 
> not accomplished. I do have more than 20 non-missing values for most of the 
> variables per row, but there are gaps (ie, missing values) between them. Thus 
I 
> want to know how many fulfill the condition of 20 non-missing values in a 
road. 
> Any clues as to how can I accomplish this with programming? 
> *
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> 
> 
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-- 
Alejandro de la Fuente
QEH/Department of International Development
Oxford University
*
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