Do I have a lower priority compared to other students who select Statistics as the 1st choice? I am worried that if I am rejected from CS department, then the AO will not put me in the same pool as the students who chose Statistics as the 1st choice.
That’s not how the process works.
In general, students are applying to a college at Michigan, not a major. CS is one of the few exceptions, though you are first applying to the college even for CS.
In your case, you will be evaluated for admissions to a home college (either LSA or engineering…sounds like LSA if your secondary interest is stats).
IF you are admitted to the home college, then you will be evaluated for CS. Michigan doesn’t admit to statistics or any other LSA major directly.
Here is the FAQ:
https://cse.engin.umich.edu/academics/undergraduate/admissions/
ok, thank you!