Date: Mon, 2 Mar 2009 13:07:05 -0800
Reply-To: sej.in.md@GMAIL.COM
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: sej.in.md@GMAIL.COM
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Subject: Re: PROC GLIMMIX: 2 questions: blocks, and covariance matrices
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On Mar 2, 2:29 pm, rh...@UNMC.EDU (Robin R High) wrote:
> SJ
>
> A couple of important questions:
>
> Why are there so many 0s? a few 1's ? and only a scattered few "counts" >
> 1? and is this your complete dataset or just a sample?
>
> Keep in mind that an important concept in statistics is the "study of
> variation" .. even for counts (unless your data is more binary in
> reality).
>
> Robin High
> UNMC
>
This is in fact the complete dataset. What I'm looking at is the
appearance of alternative male reproductive types in termite colonies
after the king is removed: mrs ("male reproductive soldier") and mn
("male neotenic"). [fn is "female neotenic" which show up
unexpectedly from time to time]. So sometimes neither show up,
usually just one or the other, and sometimes both or multiples of one
type. This is why there are a lot of "0"s. Even though mrs appears
binary here, it is not naturally binary--I've seen colonies with 2 or
3 of these guys--though these are rare. This is why I chose a poisson
distribution for the response count. My goal was to see if 1 of the 2
treatments resulted in more mrs appearing, and the same for the mn.
Sorry for not supplying all the pertinent info at the outset.
-SJ.
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