Round-robin voting

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Round-robin, paired comparison, or tournament voting methods, are a set of ranked voting systems that choose winners by comparing every pair of candidates one-on-one, similar to a round-robin tournament.^[1] In each paired matchup, we record the total number of voters who prefer each candidate in a beats matrix. Then, a majority-preferred (Condorcet) candidate is elected, if one exists. Otherwise, if there is a cyclic tie, the candidate "closest" to being a Condorcet winner is elected, based on the recorded beats matrix. How "closest" is defined varies by method.

Round-robin methods are one of the four major categories of single-winner electoral methods, along with multi-stage methods (like RCV-IRV), positional methods (like plurality and Borda), and graded methods (like score and STAR voting).

Most, but not all, election methods meeting the Condorcet criterion are based on pairwise counting.