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The '''Independence of Equivalent Candidates criterion''' was devised in 2005 by Thomas Smith. It was inspired by the inadequate definition of the [[Strategic nomination|independence of clones]] criterion which does not properly address rated voting systems and falsely presumes that correlated candidates are necessarily equivalent to each other. This criterion is a theoretical, rather than a practical criterion, and is used to describe the susceptibility of voting methods to the influence of candidates that are perceived by voters as equivalent.
Equivalent candidates are a group of candidates that are supportively ranked/rated in adjacent positions or equally ranked/rated, where equality is allowed. Thus, an approved and a disapproved candidate can never be "clones" as one is supportively rated and the other is not.
A voting method is said to be independent of equivalent candidates if the addition or removal of a equivalent candidate from a particular set of equivalent candidates in the tally, would only change the winner to another member of the set, if the original winner was a member of that set.
Methods that satisfy this criterion are [[approval voting]], [[range voting]], [[Schulze method]], and [[Instant-runoff voting]].
Independence of equivalent candidates is a weakened form of the [[independence of irrelevant alternatives]] criterion.
[[Binary independence condition]]
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