st: Reoprob - problem with convergence and superxt

[Andrea Mannberg <andrea.mannberg@econ.umu.se>]

Dear Statalisters,

I am trying to estimate a random effects ordered probit model of the form:


reoprob trust_trade ptreatment treatment  year99 tradeout age sex read write maleadult femaleadult oxen livestock landarea security1 security2 conflict zone , i(hhid) quadrat(12) level(95)

Where the dependent variable has 4 categories. I have tried changing the quadrature, the level, and the tolerance levels (ltol and tol) , nothing helps. Stata is having a problem of getting the "constant only" model to converge. The panel is unbalanced, perhaps that is part of the problem. However, I have estimated this model for a set of different ordinal dependent variables from the same unbalanced panel, all converge except this one. 

I've understood that the "superxt" command can be of help in these situations. I have installed it. However, when I try to run it, stata reads the command as "xtreoprob" which it does not recognize.

The code that I have used is:

superxt reoprob trust_trade ptreatment treatment  year99 tradeout age sex read write maleadult femaleadult oxen livestock landarea security1 security2 conflict zone , i(hhid) 

I must be writing the code wrong, but I don't see how to write it differently. Is it the case that superxt does not work for reoprob? If superxt does not work for reoprob, any suggestions on how to get the model to converge would be immensely appreciated. 

Thanks
Andrea



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