[Babase] MEMBERS comparison - Karl question

Karl O. Pinc babase@www.eco.princeton.edu
Tue, 27 Sep 2005 17:05:03 +0000


(BTW, this is exactly why it's important to get absences
entered after the statdate for dead individuals.)

On 09/27/2005 11:19:33 AM, Karl O. Pinc wrote:
> 
> On 09/27/2005 10:11:47 AM, Catherine Markham wrote:
>> Karl,
>> 
>> I have a question for you about MEMBERS interpolation regarding  
>> death dates.  The documentation states the following:
>> 
>> "... 14 day interpolation limit applies when the individual is dead.  
>> When there are no absences after the last census and there are more  
>> than 14 days between the last census and the Statdate the individual  
>> is placed in the unknown group from the 15th day through the day of  
>> death."
>> 
>> That makes sense to me, but I don't think I had also consciously  
>> considered the other way an individual can be placed in Group 9 on  
>> the death date - it didn't occur to me until looking into the  
>> records for ATO.
>> 
>> ATO is a female censused in Weaver's group as present on 25 May 2001  
>> and absent on the next group census day on 29 May 2001 (this absence  
>> was entered in CENSUS).  Her death date is 27 May 2001.  The old  
>> MEMBERS placed her in Weaver's group on this day, the new MEMBERS  
>> places her in the unknown group on this day.  The new MEMBERS is  
>> looking at the absence on 29 May 2001 no differently than it would  
>> for, say, any male who disappears from a study group - it  
>> essentially considers ATO's group to be 9 on the 29th.  So it turns  
>> out that the 27th is a perfect mid-point between presence in  
>> Weaver's and placement in Group 9.  This makes the day's group  
>> placement more or less a coin toss - it could have been Weaver's or  
>> it could have been (and in this case it was) Group 9.
>> 
>> Did I follow the logic of that correctly?
> 
> Yes.  Exactly.  In fact, this caught me too when I went to review
> the members comparison.  IIRC I'd explicitly put in an example
> like this in the documentation, but even so I'd forgotten again
> until it came up in real data.
> 
> Karl <kop@meme.com>
> Free Software:  "You don't pay back, you pay forward."
>                  -- Robert A. Heinlein
> 
> _______________________________________________
> Babase mailing list
> Babase@www.eco.princeton.edu
> http://www.eco.princeton.edu/mailman/listinfo/babase
> 
> 

Karl <kop@meme.com>
Free Software:  "You don't pay back, you pay forward."
                  -- Robert A. Heinlein