Bookmark and Share

Notice: On March 31, it was announced that Statalist is moving from an email list to a forum. The old list will shut down on April 23, and its replacement, statalist.org is already up and running.


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: st: Keeping specific observations


From   Nick Cox <njcoxstata@gmail.com>
To   statalist@hsphsun2.harvard.edu
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 <afeef745@hotmail.com> wrote:

> Shouldnt "drop if v1 == . " work?

From: Eleimon2.Gonis@uwe.ac.uk

>> 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.
*
*   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/


© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   Site index