Re: st: gologit2

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

At 03:28 AM 1/30/2007, Maarten buis wrote:
> --- Juan Jose Miranda <unicojm@yahoo.es> wrote:
> > So, I started to use generalized "gologit2", but results show me
> > that 4% of observations have negative probability.
> > So I would like to know how to reduce observation with negative
> > probability or another method to estimate.
>
> Richard Williams (author of gologit2) has written a FAQ on gologit2,
> and negative predicted probabilities are discussed there:
> http://www.nd.edu/~rwilliam/gologit2/tsfaq.html
> Hope this helps,
> Maarten
Thanks for pointing this out Maarten.  My experience has been that 
models that produce negative predicted probabilities often have other 
problems, e.g. the models are way too complicated given the amount of 
data available.  The FAQ has suggestions for dealing with this, but 
if worse comes to worst you may want to switch to a non-ordinal 
method such as mlogit.


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