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Re: st: Observations differ
From
Nick Cox <[email protected]>
To
[email protected]
Subject
Re: st: Observations differ
Date
Sun, 23 Sep 2012 13:18:39 +0100
I imagine one model is using fewer observations because of missing
values in one or more predictors, a problem, which doesn't bite for
the other model. Or there could be problems if predictors are
constant.
A strategy includes
0. Look carefully at the structure of missing values. See e.g.
-misstable-, -nmissing- (SJ).
1. Identify the model using fewer observations.
2. Define
gen used = e(sample)
after fitting that model.
3. Fit the other model using
... if used
4. Compare fits if possible.
Nick
On Sun, Sep 23, 2012 at 1:02 PM, Shittu, Aminu <[email protected]> wrote:
> I am trying to compare, using likelihood ratio test, between the full and reduced model in a random effect logistic regression; but the output is saying "observations differ: 3356 vs. 3583." How can I handle this problem, please.
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