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
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