RE: st: likelihood ratio test error message

[Richard Williams <Richard.A.Williams.5@nd.edu>]

At 09:28 PM 3/5/2004 -0600, Rivera, Semilla  M. wrote:
> Thanks so much, Richard.  I will try this.  :)
Another approach (there are many) is to use commands like

. gen touse = !missing(y, x1, x2, x3, x4)
. logit y x1 x2 if touse

That is, you create a variable, e.g. touse, which is coded 1 for the cases 
you want to analyze and 0 otherwise.  In this case, you are restricting 
your analysis to cases with complete data on y, x1, x2, x3 and x4.  You can 
also make the selection more complicated if you need to, e.g. limit it to 
females with nonmissing data.

The above approach, of course, assumes that you want to do listwise 
deletion of missing data.  That is probably the most common strategy, but 
there are others, e.g. impute values for the missing data.

Finally, there is a -force- option on the -lrtest- command that might make 
your original error go away, but you probably don't want to use it, i.e. it 
probably won't give you the right results.

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