Plurality criterion: Difference between revisions
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<h4 class=left>Complying Methods</h4>
<p>[[Plurality voting|First-Preference Plurality]], [[Approval voting]], [[IRV]], and many [[Condorcet method|Condorcet methods]] (using winning votes as defeat strength) satisfy the Plurality criterion. [[Condorcet method|Condorcet methods]] using margins as the measure of defeat strength fail it, as does [[Raynaud]] (using either winning votes or margins as the measure of defeat strength), and also [[Minmax|Minmax(pairwise opposition)]]. </p>
<p>Example where [[Score voting]] fails if the definition of the criterion is extended to scored ballots:</p>
<p>3 A:1</p>1 C:5 B:4
1 D:5 B:4
Scores are A 3, C 5, B 8, D 5, making B the winner. Yet when looking at the rankings:
3 A
1 C>B
1 D>B
B is preferred on 2 ballots, while A is preferred 1st on 3 ballots. <h4 class=left>Commentary</h4>
When the Plurality criterion requires that ''B'' not be elected, it means that even if all the voters who gave ''B some'' ranking were to elevate him to the top position, he would still not be the [[Plurality voting|First Preference Plurality]] winner.
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