Hi everybody,
I'm doing a negative binomial regression using Proc Genmod on SAS
where this is part of the output
Parameter DF Estimate Error Limits Square
Pr > ChiSq
TRT 1 1 -0.2397 0.1102 -0.4557 -0.0237 4.73 0.0296
TRT 2 0 0.0000 0.0000 0.0000 0.0000
Dispersion 1 0.1268 0.0315 0.0651 0.1885
NOTE: The negative binomial dispersion parameter was estimated by
maximum likelihood.
LR Statistics For Type 1 Analysis
2*Log Chi-
Source Likelihood DF Square Pr > ChiS
Intercept 5189.2817
PAIR 5253.0473 34 63.77 0.0015
TRT 5257.5618 1 4.51 0.0336
LR Statistics For Type 3 Analysis
Chi-
Source DF Square Pr > ChiSq
PAIR 34 65.03 0.0011
TRT 1 4.51 0.0336
I'm trying to reproduce this analysis in Stata but I don't know how to
get the Type 1 and Type 3 Statistics. Anybody knows how to do this?
Another question is why are the p-values of the contrast of tratment 1
wrt to treatment 2 (0.0296) and the one given for TRT (0.0336)
different?
Thank you very much.
Victor Enciso
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