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Re: st: which -cmp- option to use for poisson model with count data?
From
Nick Cox <[email protected]>
To
[email protected]
Subject
Re: st: which -cmp- option to use for poisson model with count data?
Date
Thu, 3 May 2012 13:40:47 +0100
We've got to nail this one.
Laura's not said so, but what I wildly imagine is this: Somehow Laura
is counting how many experts do or say something. There is a fixed
number of experts being recorded, so in principle any number from 0 to
all of them could be observed. That's the outcome or response
variable.
If that is so, I don't think this is very Poisson-like. It's not like
number of children, where there is no known upper limit. You may have
17 children, but it could be 18 or 19 or whatever. If the upper limit
is known and definitely bites some of the time, that's not
Poisson-like. The upper limit can vary too; that's fine.
Please Laura: You should give substantive detail here to describe the
process. Describe how the data are produced. Otherwise, this is just
going round in circles (or more likely commenters will give up in
despair).
Nick
On Thu, May 3, 2012 at 1:12 PM, Brendan Halpin <[email protected]> wrote:
> On Thu, May 03 2012, Laura R. wrote:
>
>> dependent variable:
>> - experts
>> - in this sample: 0 to 5
>> - 0 should be in the analysis (not "missing")
>> - in other samples, it can be more than 5, but naturally not less than 0
>
> This makes it sound as if the DV isn't bounded at 5, but simply that
> there are no higher values observed in this sample. If that's true,
> models for counts (poisson etc) should be fine.
>
> Brendan
> --
> Brendan Halpin, Department of Sociology, University of Limerick, Ireland
> Tel: w +353-61-213147 f +353-61-202569 h +353-61-338562; Room F1-009 x 3147
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