[R] Comparing Negative Binomial Regression in Stata and R. Constants differ?

[Peter Dalgaard]

Prof Brian Ripley <ripley at stats.ox.ac.uk> writes:

> > report.  In the Stata output, they report alpha, same as 1/theta from 
> > the R glm.nb output.  Except for minor differences in standard errors, 
> > only the intercept estimates markedly differ.
> 
> What are the variable codings used?  Intercepts depend on coding of 
> factors, and that applies to any sort of regression.

..and the fact that the difference between the two intercepts equals
the gender effect quite strongly suggests that Stata has gender coded
1 for females and 2 for males.

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark      Ph: (+45) 35327918
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