[R] basic question predict GLM offset

[smfa]

Hi, 

I know this is probably a basic question... But I don't seem to find the
answer. 

I'm fitting a GLM with a Poisson family, and then tried to get a look at the
predictions, however the offset does seem to be taken into consideration: 

model_glm=glm(cases~rhs(data$year,2003)+lhs(data$year,2003),
offset=(log(population)), data=data, subset=28:36, family=poisson()) 

predict (model_glm, type="response") 

I get cases not rates... 

I've tried also 

model_glm=glm(cases~rhs(data$year,2003)+lhs(data$year,2003)+
offset(log(population)), data=data, subset=28:36, family=poisson()) 

with the same results. However when I predict from GAM, using mgcv, the
predictions consider the offset (I get rates). 

I'm missing something? 

I would appreciate any comment, 

thanks 

Sandra 


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