You've got it right. Just multiply the predicted values by the exposure time or
number of cases and that will get you what you want. Note that, depending on
the scale of the predictions, you might want to do all the predictions and
+log(offset) on the log scale and then exponentiate it. Should
Dear all,
the help file for predict.gbm states that "The predictions from gbm do not
include the offset term. The user may add the value of the offset to the
predicted value if desired." I am just not sure how exactly, especially for
a Poisson model, where I believe the offset is multiplicative ?
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