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I wouldn't worry too much about the lack of correspondence. Some programs don't send the perfunctory "We really liked you..." emails. My advice is to rank the programs as you wish, even if you haven't had subsequent correspondence. If you match at a program, that means that they ranked you high enough to "match" there, even if you weren't at the top of their list. But make sure to rank all of the programs at which you interviewed unless your impressions were so negative that you would rather take a chance with the scramble than to match at that program. Of the students I have known who didn't match, most had cut a gaping hole in their safety net and didn't rank enough programs.
