Condorcet method: Difference between revisions

imported>Araucaria
imported>James Green-Armytage
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Ballots are counted by considering all possible sets of two-candidate elections from all available candidates. That is, each candidate is considered against each and every other candidate. A candidate is considered to "win" against another on a single ballot if they are ranked higher than their opponent. All the votes for candidate Alice over candidate Bob are counted, as are all of the votes for Bob over Alice. Whoever has the most votes in each one-on-one election wins.
 
If a candidate is preferred over all other candidates, that candidate is the [[Condorcet Criterion|Condorcet candidate]]. However, a Condorcet candidate may not exist, due to a fundamental [[Voting paradox|paradox]]: It is possible for the electorate to prefer A over B, B over C, and C over A simultaneously. This is called a circularmajority tierule cycle, and it must be resolved by some other mechanism.
 
==== Counting with matrices ====
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When the sum matrix is found, the contest between each candidate is considered. The number of votes for runner over opponent (runner,opponent) is compared the number of votes for opponent over runner (opponent,runner). The one-on-one winner has the most votes. If one candidate wins against all other candidates, that candidate wins the election.
 
The sum of all ballot matrices, the '''Condorcet pairwise matrix''', is the primary piece of data used to resolve circularmajority tiesrule (also called circular ambiguities)cycles.
 
=== Key terms in ambiguity resolution ===