Hi all:
I have a question about poisson regression.
My data:
drug result count
1 1 8
1 2 54
2 1 20
2 2 44
My model:
model<- glm(count ~ drug*result, family = poisson)
My result:
summary(model)
Coefficients:
Estimate Std. Error z value Pr(>|z|)
(Intercept) 2.0794 0.3536 5.882 4.06e-09 ***
drug2 0.9163 0.4183 2.190 0.0285 *
result2 1.9095 0.3788 5.041 4.64e-07 ***
drug2:result2 -1.1211 0.4650 -2.411 0.0159 *
Calculation of coefficients:
Intercept: drug=1 and result=1,the corresponding count is 8.So log(8) is
2.079442 which is Intercept.
My question: How is drug2 calculated? log(64)-log(62) or something like
that(indicates the difference between drug2 and drug1) ? I've searched and
tried many times for all possible solutions,but the result is not 0.9163.So,how
is drug2 calculated ?
Many thanks!
Best
[[alternative HTML version deleted]]
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
