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Ranked Pairs (RP) is a tournament-style system of ranked voting first proposed by Nicolaus Tideman in 1987.[1][2]
Ranked pairs begins with a round-robin tournament, where the one-on-one margins of victory for each candidate are compared to find a majority-preferred candidate; if such a candidate exists, they are immediately elected. Otherwise, if there is a Condorcet cycle—a rock-paper-scissors-like sequence A > B > C > A—the cycle is broken by dropping the "weakest" elections in the cycle, i.e. the ones that are closest to being tied.[3]