Approximate Sorting
نویسندگان
چکیده
We show that any randomized algorithm to approximate any given ranking of n items within expected Spearman’s footrule distance n/ν(n) needs at least n (min{log ν(n), log n} − 6) comparisons. This bound is tight up to a constant factor since there exists a deterministic algorithm that shows that 6n(log ν(n) + 1) comparisons are always sufficient.
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