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=== Equal Vote Criterion ===
Otherwise known as the Equality Criterion. Any voting method or election which passes the Test of Balance passes the Equal Vote Criterion and can be said to guarantee an Equally Weighted Vote.
=== The Test of Balance ===
Voting Methods which ensure an Equally Weighted Vote with any number of candidates include Approval Voting, Score Voting, STAR Voting, as well as a number of others. In general Cardinal Voting methods ensure an Equally Weighted Vote for each voter. Many Condorcet methods (most that can be calculated only with the [[Pairwise counting|pairwise counting]] matrix, most Condorcet-cardinal hybrids, etc.) also pass the criterion.
Choose One Plurality Voting onlydoes satisfiesnot satisfy the Equal Vote Criterion in elections with two candidates only. Instant Runoff Voting (often referred to as Ranked Choice Voting) does not satisfy andthe Equal Vote Criterion. Any voting method will satisfy the Equal Vote Criterion in elections with two candidates only.
=== '''Vote unitarity''' ===
One generalizationapplication of the Equally Weighted Vote for the multi-winner or proportional context is [[Vote unitarity|vote unitarity]]. The basic idea is that the vote should stay equally weighted throughout the election tabulation. A votersvoter's influence on electing subsequent winners should directly depend on the amount of support they gave for prior winners. This means that the vote weight is conserved throughout the process.
There is an important nuance to this with regards to [[Surplus Handling]]; if, say, every voter gives one of the winners a perfect score, then instead of everyone's vote having no influence on the other winners, vote unitarity tries to ensure some kind of proportional decrease in voting power such that every voter still has a the correct amount of influence on the remaining winners. The simplest implementation of this is with [[Sequentially Spent Score]].
In summary, there is a proportional relationship between how much support the voters give to the winners and the amount of influence that is removed from the voters, to ensure that every voter has a chance to fairly elect someone they prefer. The prominent [[Single transferable vote|Single Transferable Vote]], and [[Reweighted Range Voting]] methods fail vote unitarity.
== Notes ==
Some voting methods which pass the Equal Vote Criterion (which has also been called "Frohnmayer balance" in reference to its creator) don't pass a generalized form which refers to more than two voters being able to cancel each other out.
STAR may or may not pass the generalized criterion depending on how it is defined. Example:<blockquote>Example modeled off of <nowiki>https://rangevoting.org/TobyCondParadox.html</nowiki>:
3 A:5>B:4>C:0
2 B:5>A:4>C:0
2 B:5>C:4>A:0
2 C:5>A:4>B:0
Scores are A 31, B 32, C 18, with A pairwise beating B and thus being the STAR winner. Removing 6 votes that constitute a cycle and a kind of pairwise tie and a definite scored tie for A, B, and C (2 A:5>B:4>C:0, 2 B:5>C:4>A:0, 2 C:5>A:4>B:0 votes, which give a total of 9 points to A, B, and C, and create a [[Condorcet cycle]] between the three where A>B, B>C, and C>A are all matchups of 4 to 2) yields:
1 A>B>C
2 B>A>C
Without even looking at the scores, B must win here, since A and B are unanimously preferred as the top 2 candidates and a majority prefers B>A. <ref>https://www.reddit.com/r/EndFPTP/comments/f51ww6/the_meaning_of_one_person_one_vote/fhwk752/</ref></blockquote>If it is considered a kind of "pairwise tie" for there to be a Condorcet cycle between the three candidates where each candidate's pairwise matchups are either 4 to 2 or 2 to 4, then STAR fails. But if one requires the pairwise tie to be an exact pairwise tie between all candidates, then this example doesn't show a failure for STAR.
The passing or failure of Condorcet methods of this generalization is also similarly dependent on how a pairwise tie is interpreted (shown in https://rangevoting.org/TobyCondParadox.html).
Approval voting and Score voting pass the generalized form of the criterion, since removing any number of votes that constitute a scored tie for all candidates won't change the difference in scores between any candidates, thus since the winner must have originally had more approvals/points than all other candidates, they will still have more and thus still win.
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