st: xtnbreg discontinous region encountered after rescaling

[hl <hl.statlist@googlemail.com>]

I am running a series of fixed effects negative binomial panel 
regressions (xtnbreg, fe) on different dependent variables. I have 
encountered some specifications that do not converge or cannot be 
computed due to discontinous regions before. However, one specific 
regression that worked fine suddenly returns
discontinuous region encountered
cannot compute an improvement
r(430);

after I rescaled one independent variable. I didnt change anything 
substantial, just divided by factor 100 - how is that possible?
thanks very much,


Hl.
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