I have to compare three groups (each group is a customer to a subscription box company).
Group A received treatment A. Group B received treatment B. Group C received no treatment.
We count the total number of boxes sold in each group (i.e. we are modelling count data)
I want to compare the mean number of boxes in group A and B vs the control (to see if the uplift is greater)
For this data ~2% of Group A got a box, ~2.1% of Group B got a box, and ~1.1% of Group C got a box.
What tests could we run to compare the means or the difference in uplift vs control for Group A and Group B?
I don't think a t-test or a Mann-Whitney test is appropriate here (though I am willing to be proven wrong!)