May's Theorem characterizes simple majority rule among methods for aggregating a group's two-option preferences into a single collective decision, showing that majority rule is the unique method satisfying four conditions: treating every voter equally, treating both options equally, responding positively to a swing in any voter's preference, and depending only on the votes actually cast. Named for Kenneth May, it is a foundational result of social choice theory giving an axiomatic justification for majority voting.
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StatementMajority vote is the unique ranked social choice function between two candidates that satisfies Anonymity, Neutrality, Decisiveness, Positive response, and Ordinality. 2 Classification
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1. Wikipedia: May's theorem
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In social choice theory, May's theorem, also called the general possibility theorem, says that majority vote is the unique ranked social choice function between two candidates that satisfies the following criteria: Anonymity: the decision rule treats each voter identically (one vote, one value).
2. May's theorem, Wikipedia
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In social choice theory, May's theorem, also called the general possibility theorem, says that majority vote is the unique ranked social choice function between two candidates that satisfies the following criteria: Anonymity: the decision rule treats each voter identically (one vote, one value).
In Group: Social Choice and Voting Theory, Lead paragraph
In social choice theory, May's theorem, also called the general possibility theorem, says that majority vote is the unique ranked social choice function between two candidates that satisfies the following criteria: Anonymity: the decision rule treats each voter identically (one vote, one value).
View the Source3. Wikidata: May's Theorem
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The theorem was first published by Kenneth May in 1952.
Wolfram MathWorld: May's Theorem
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Applied Mathematics Game Theory
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