st: Piecewise model and LR chi2

[nanss115@sapo.pt]

I'm using a piecewise constant exponential model to study unemployment  
durations. I've estimated my model and the coefficients seem fine but  
in my estimation results in not getting the LR chi2 statistic. I'm  
guessing that this is the reason why my model is not performing well  
in the linktest but I honestly don't know what can cause stata to not  
provide the LR chi2 statistic. I've expanded my data and created the  
dummies for the duration and everything looks alright but obviously is  
not.
Any help you could give would be great.
Kind regards
Nádia

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