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Re: st: Keeping specific observations
From
Nick Cox <[email protected]>
To
[email protected]
Subject
Re: st: Keeping specific observations
Date
Fri, 31 Aug 2012 18:00:26 +0100
observations. So, try
bysort ID (v1) : drop if missing(v1[1])
The logic here is that if all values are missing for an individual,
then after sorting the first value of -v1- will necessarily be missing
too, and that is a criterion for -drop-ing.
Nick
On Fri, Aug 31, 2012 at 5:46 PM, Afif Naeem <[email protected]> wrote:
> Shouldnt "drop if v1 == . " work?
From: [email protected]
>> I would appreciate your help with the following conundrum. Assume I have a dataset that looks like this:
>>
>> Year ID v1
>> 2000 1 2
>> 2001 1 2
>> 2002 1 3
>> 2000 2 3
>> 2001 2 .
>> 2002 2 3
>> 2000 3 .
>> 2001 3 .
>> 2002 3 .
>>
>> What I want to achieve is to only keep those individuals that appear with any non-missing values for v1 for any of the years in the dataset.
>>
>> In other words, I don't think that a command: "keep if v1<." would do, because that would also take out the 2001 observation for the second individual (ID==2), which I'd like to remain in place.
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