st: Negative predictions after trnbin0

[D Jimenez Rubio <djr109@york.ac.uk>]

Dear all,
I have used a truncated negative binomial model (trbin0) for the
conditional number of visits to the doctor. I have found out that the
predictions after the estimation of the positive number of visits is
sometimes negative. Is there any one who could help me to understand why
that happens?

Many thanks in advance,

Dolores

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