我的数据看起来像这样
$ Sum.Insured.Band: chr "a) $0 - $50k" "a) $0 - $50k" "a) $0 - $50k" "a) $0 - $50k" ...
$ Frequency : num 0 0 0 0 0 0 0 0 0 0 ...
$ Premium.Exposure: num 1 1 1 1 1 0 1 1 1 1 ...
当我适合glm时
glm(Frequency ~ Sum.Insured.Band , family = poisson,
data = train_df, weight = Premium.Exposure)
我的拟合值始终高于实际值,即使是平均水平也是如此。怎么会这样?汇总的总和不应该接近实际总和吗?在每种情况下,情况总是如何?