I dont think there's a clear answer to your question. I think Cornell's international brand is very strong (not just in India but the rest of Asia as well) whereas Duke is comparatively unknown. However, the flip side to that is that if you plan to stay in the US for 4-5 years, at that point the brand of your school is probably going to become relatively irrelevant. The focus then shifts to what you've achieved in those 4-5 years of work as opposed to which school you graduated from. Thus, I'd recommend shifting your efforts to focusing on which school will leave you better placed for your job post-graduation in the US. For example, do you want to work in NY? (Cornell has a location advantage) Do you want to work for Booz? (Booz recruits at Duke and not at Cornell)
Both programs are equally good overall and there is really no clear winner.
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