Finding the median of three permutations under the Kendall-tau distance
نویسندگان
چکیده
Given m permutations π, π . . . π of {1, 2, . . . , n} and a distance function d, the median problem is to find a permutation π that is the ”closest” of the m given permutations. More formally, we want to find π such that, for all π ∈ Sn, ∑m i=1 d(π , π) ≤ ∑m i=1 d(π, π ). (ICI, BIBLIO DE CE QUI A ETE FAIT) In this article, we choose to study the problem under the Kendall-Tau distance, denoted dKT , that count the number of pairwise disagreements between two permutations. More formally we have, for permutation π and σ that
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