st: ml check shows errors but ml maximize works

[Alita Nandi <alita.nandi@chrr.ohio-state.edu>]

Hello,

--ml check-- gives the error message "cannot find feasible values" when it 
is testing to see whether the likelihood evaluator (the program that I have 
written to calculate the log-likelihood) works or not. But when I run --ml 
maximize-- without running --ml check-- before it, the maximization works 
and I get the estimates. By using --ml search-- before --ml maximize-- I 
get the same estimates. What I want to know is whether it is possible for 
--ml check-- to show that there are problems with my likelihood evaluator 
even if there is none. If not, what kind of errors in my programming (or 
perhaps the data set) may cause this discrepancy? I have not written the 
program code in this email so as not to clutter it. But please let me know 
if it is necessary to see the program code in order to be able to provide 
answers to my questions and I will do so.

I am running Intercooled STATA Version 8 on Windows.

Thanks in advance,
Alita Nandi

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