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The Condorcet candidate or Condorcet winner () of an election is the candidate who, when compared with every other candidate, is preferred by more voters. Informally, the Condorcet winner is the person who would win a two-candidate election against each of the other candidates. A Condorcet winner will not always exist in a given set of votes, which is known as Condorcet's voting paradox. When voters identify candidates on a left-to-right axis and always prefer candidates closer to themselves, a Condorcet winner always exists. A voting system satisfies the Condorcet criterion if it chooses the Condorcet winner when one exists. Any method conforming to the Condorcet criterion is known as a Condorcet method. It is named after the 18th century mathematician and philosopher Marie Jean Antoine Nicolas Caritat, the Marquis de Condorcet. == Relation to other criteria == The Condorcet criterion implies the majority criterion; that is, any system that satisfies the former will satisfy the latter. Because of this, Arrow's impossibility theorem shows that any method which satisfies the Condorcet criterion will not satisfy independence of irrelevant alternatives. The Condorcet criterion is also incompatible with the later-no-harm criterion, the participation criterion, and the consistency criterion. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Condorcet criterion」の詳細全文を読む スポンサード リンク
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