Copeland's method

Copeland's method, also called Llull's method or Ranked-Robin, is a ranked-choice voting system based on scoring pairwise wins and losses.

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In the system, voters rank candidates from best to worst on their ballot. Candidates then compete in a round-robin tournament, where the ballots are used to look up which candidate would be preferred by a majority of voters in each matchup. The candidate is the one who wins the most matchups (with ties winning half a point).

Copeland's method falls in the class of Condorcet methods, as any candidate who wins every one-on-one election will clearly have the most victories overall. Copeland's method has the advantage of being likely the simplest Condorcet method to explain and of being easy to administer by hand. On the other hand, if there is no Condorcet winner, the procedure can give frequent ties; as a result, it is generally used in low-stakes elections.

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