I would appreciate help with creating the following value, I can't seem to
get it right:
I have data with 4 vars in each record as follows:
1. farmID is an ID variable for farm
2. cowID is an ID variable for cow (within farmID)
3 enterPen is the date on which a cow enters Pen
4 exitPen is the date on which the cow exits Pen
There are multiple cows within each farm, and their enterPen and exitPen
dates vary individually.
What I need is a variable that contains the count of cows within the same
farmID which have entered, but not yet exited the Pen on the date an
individual cow exits the Pen,
i.e.a count of "other cows" within the same farmID whose enterPen date is
< exitPen date for each individual cow (within the same farmID) and whose
exitPen date (the "other cows" ) is > the exitPen date for the individual
cow ...
I can't seem to get the ifs to work correctly across different records,
probably because I'm not very good at looping.
thanks
Buzz Burhans
Department of Animal Science
Cornell University
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