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Re: st: strange test statistic with ologit
Stephan Rudolfer <[email protected]> reported a problem with
the estimation table header from -ologit-.
> Consider the following output:
>
> . * fit PO model +/- ulnar sensories
> . ologit drdiag *N*
>
> ...
>
> Ordered logistic regression Number of obs = 958
> LR chi2(28) = 1275.68
> Prob > chi2 = 0.0000
> Log likelihood = -481.66917 Pseudo R2 = 0.5698
>
> ------------------------------------------------------------------------------
> drdiag | Coef. Std. Err. z P>|z| [95% Conf. Interval]
> -------------+----------------------------------------------------------------
> ...
> -------------+----------------------------------------------------------------
> /cut1 | -17.09747 4.765666 -26.438 -7.756936
> /cut2 | -12.30247 4.741235 -21.59512 -3.009824
> /cut3 | -7.826134 4.744828 -17.12583 1.473559
> ------------------------------------------------------------------------------
> Note: 8 observations completely determined. Standard errors questionable.
>
> . predict p1-p4,p
>
> . drop *N_us* p1-p4
>
> . ologit drdiag *N*
>
> ...
>
> Ordered logistic regression Number of obs = 958
> F( 22, .) = .
> Prob > F = .
>
> ------------------------------------------------------------------------------
> drdiag | Coef. Std. Err. z P>|z| [95% Conf. Interval]
> -------------+----------------------------------------------------------------
> ...
> -------------+----------------------------------------------------------------
> /cut1 | -16.51915 4.513598 -25.36564 -7.672665
> /cut2 | -12.14342 4.486871 -20.93752 -3.349314
> /cut3 | -7.916497 4.498279 -16.73296 .8999674
> ------------------------------------------------------------------------------
> Note: 8 observations completely determined. Standard errors questionable.
>
> I am astonished that Stata has given the F-statistic instead of the
> chi-squared one in the second model fitted. This seems to have occurred
> just because I deleted the last six variables of the first model. Having
> asked two Stata experts, who told me that they had never seen anything like
> this, I am hoping that someone on statalist will be able to clarify the
> situation for me. Many thanks in advance.
If Stephan will send me a private email with a dataset that will reproduce
the above, I will investigate. I would also appreciate a log containing the
output from the following commands:
***** BEGIN:
about
update query
which ologit
which _coef_table
which _coef_table_header
***** END:
--Jeff
[email protected]
*
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