st: outoput from prvalue following zinb

["Fotland, Knut Erik" <knut.fotland.12@ucl.ac.uk>]

I am running a zero-inflated negative binomial regression model on a dataset of 720 observations, in an attempt to determine how socio-economic factors and popular support affect violent events in a country. The dependent variable is a count variable for events per month. The independent variables are a mix of dummy-coded, ordinal and interval variables. 

My problem is that, after running predicted values (prvalue-command) I get no numbers for the probabilities, the Pr(Always 0|z)-value shows zero, but the other Pr(y i) is missing. Having thought this may be due to my settings for the chosen variables were incompatible with the sample range I changed them to relatively moderate values. That did not alter the result, and I got the same missing phenomenon. Then I tried having only one variable differ in the two models. The command I ran were: "prvalue, x(var1=0) rest(mean) diff", but I got the same missing phenomenon again. 

I would greatly appreciate some input on what I am doing wrong. 

Knut Erik

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