Re: st: unrecognized brant command

[Richard Williams <richardwilliams.ndu@gmail.com>]

At 08:02 AM 11/12/2012, Linda.Kampata@student.uib.no wrote:
> Thanks Nick,
> I managed to get the brant command from a lower version of the spost.
>
> However, when i run the brant command I get the following error message.
>
> . brant, detail
> not all independent variables can be retained in all binary logits
> brant test cannot be computed
> r(999);
>
>
>
> What does this error message mean in a less technical language? When I
> click on the r(999) I get a stata dialogue message which reads "no
> entries found for search on "r(999)"."
>
> Thanks,
> Linda

The -brant- command takes your ordinal dependent variable, 
dichotomizes it in various ways, and then runs a series of logistic 
regressions. So, if your DV has 4 values, the first logistic 
regression is category 1 versus categories 2, 3, 4. Then, it does 1 & 
2 versus 3 & 4, and finally, 1, 2, 3 vs 4. Your error message is 
telling you one or more of those logistic regressions can't be run 
without dropping some variables. Perhaps category 1 only has 7 cases 
and your model has 8 variables. My guess is you will need to simplify 
the model or combine categories. You can run the logistic regressions 
yourself to pinpoint exactly where and why the problem is occurring. 
But I would start just by doing a frequency of the DV to see if any 
categories (especially the first and the last) have very small 
frequency counts.

-------------------------------------------
Richard Williams, Notre Dame Dept of Sociology
OFFICE: (574)631-6668, (574)631-6463
HOME:   (574)289-5227
EMAIL:  Richard.A.Williams.5@ND.Edu
WWW:    http://www.nd.edu/~rwilliam

*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/faqs/resources/statalist-faq/
*   http://www.ats.ucla.edu/stat/stata/