Dear Statalist,
I am analyzing a balanced panel dataset with the dependent variable of interest being a count variable. Additional to the observed count the upper bound of possible values is also known (i.e., I observe s successes in n trials for different groups i over several years t).
Due to this data structure, I want to analyze the count variable conditional on the exogenous variables and conditional on the upper bound.
I am not sure whether xtnbreg combined with the exposure-option (like in the code shown below) really solves my problem; the code I used is
xtnbreg depvar indepvars, exp(number of trials)
What makes the situation more complicated is that I got disproportionately many zeros in the data making a zero-inflated model more appropriate. I didn't find a clue within the STATA documentation whether any estimators for such a PANEL problem are implemented. Perhaps you can provide me with some guidance.
Any help is welcome!
Stefan
BEGIN:VCARD
VERSION:2.1
N:Wagner;Stefan
FN:Wagner, Stefan
EMAIL;PREF;INTERNET:[email protected]
REV:20021007T114312Z
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