On Mon, 5 Apr 2004, Petersen, Karen wrote:
> I have run into a perplexing problem. I am using logit to analyze an outcome
> variable (mid)
>
> logit mid illibdem1 limdyn1 absdyn1 auth1 pers1 cwpceyrs_werner rel_cap
> econ_dep1 econ_dep2 rel_energy allies if cat2_2==11 & exclude2==0 &
> initiate~=2, cluster(dyad_id)
>
> and get the following message about one of my explanatory variables (absdyn1):
>
> note: absdyn1 != 0 predicts failure perfectly
> absdyn dropped and 68 obs not used
> Does anyone know why I get the above error message when the variable does not
> appear to actually be a "perfect predictor"?
>
I suspect that it is a perfect predictor in the logit because you are
losing cases due to misssing data on the other variables in the equation.
------------------------------------------------------------------------
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