I don't know exact percentages, but if you have top tier publications, or at the very least have relevant research experience, solid recommendation letters & fa

I don't know exact percentages, but if you have top tier publications, or at the very least have relevant research experience, solid recommendation letters & faculty sponsorship then your chances of being admitted increase dramatically. Getting into top graduate schools isn't easy. GPA wise, usually your junior/senior year is the most important aspect. Good luck!