回复：读州大的好处:深造的机会更多.

That's because ivy graduates do not have to go to graduate school right after college.  They have more chance and want to spend time to explore their careers.  Public collge education leans to professional training and ivy college education are mostly liberal arts education.  Public college graduates may have better idea what they want to do and tend to want to go to graduate school to save time, and also probably, demonstrate that they are the best in the public colleges.  Pblic college graduates tend to have fewer opportunities than ivy graduates is probably another reason.  You can not just compare best students in public colleges to average ivy college students.