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Re: st: RE: Creating missing data


From   Keith Dear <keith.dear@anu.edu.au>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: RE: Creating missing data
Date   Thu, 04 Nov 2004 12:36:02 +1100

But celdjt said he wanted to do this for every fifth *multiple-record* case. He could first drop the single-record cases, apply Nick's code, then append them back. Or is there a neater way?
kd

At 12:18 PM 4/11/04, you wrote:

Suppose your identifiers run 1, 2, ... . If this isn't true,

. egen id = group(whateverisyourid)

will make it so.

Now, if I understand you correctly, you want to

. bysort id (entrytime):
        replace somevar = . if _n == 1 & mod(id,5) == 0

Nick
n.j.cox@durham.ac.uk

celdjt@umich.edu

> My
> question is about making an adjustment to the surrogate data set. The
> surrogate data set contains about 3500 cases, some of which
> have just one
> record per case, and others have multiple records. Each record has a
> variable recording an entering time and an exit time for that record.
> Hence, single record cases have one entry time and one exit
> time; multiple
> record cases have multiple entry and multiple exit times. I
> would like to
> convert the first entry time for every fifth multiple-record
> case in this
> data set into a missing value. Are there any suggestions for
> how this might be done.

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