* Note that the last-place votes are only used to eliminate a candidate in a voting round where no candidate achieves an absolute majority; they are disregarded in a round where any candidate has 51% or more. Thus last-place votes play no role in the final round.
== UseIn practice ==
The voting rounds used in the [[reality television]] program ''[[Survivor (TV series)|Survivor]]'' could be considered a variation of Coombs' method, with sequential voting rounds. Everyone votes for one candidate they support for elimination each round, and the candidate with a plurality of that vote is eliminated. A strategy difference is that sequential rounds of voting means the elimination choice is fixed in a ranked ballot Coombs' method until that candidate is eliminated.
=== Potential for strategic voting ===
Like [[anti-plurality voting]] and the [[Borda count]], Coombs' rule is extremely vulnerable to strategic voting,. and asAs a result, it is knownmost moreoften considered as an example of a [[Pathological (mathematics)|pathological]] socialvoting choicerule functionrather than asin aany serious use<ref name=":0" />. Coombs' method is extremely sensitive to [[Instant-runoff voting#Invalid ruleballots and incomplete ballots|incomplete ballots]], [[Tactical manipulation of runoff voting#Compromise|compromising]], [[Tactical manipulation of runoff voting#Push over|push-over]], and [[strategic nomination|teaming]], and the vast majority of voters' effects on the election come from how they fill out the bottom of their ballots<ref name=":0">[http://www.accuratedemocracy.com/l_data.htm "Data on Manipulability"]</ref>. As a result, voters have a strong incentive to rate the strongest candidates last to defeat them in earlier rounds.
This results in a [[Keynesian beauty contest|Keynesian beauty pageant]] that is extremely sensitive to minor variations in the perceived strengths of candidates.
Coombs' method is extremely sensitive to [[Instant-runoff voting#Invalid ballots and incomplete ballots|incomplete ballots]], [[Tactical manipulation of runoff voting#Compromise|compromising]], [[Tactical manipulation of runoff voting#Push over|push-over]], and [[strategic nomination|teaming]]; the vast majority of voters' effects on the election comes from how they fill out the bottom of their ballots<ref>[http://www.accuratedemocracy.com/l_data.htm "Data on Manipulability"]</ref>. As a result, voters have a strong incentive to rate the strongest candidates last to defeat them early on. This results in a [[Keynesian beauty contest|Keynesian beauty pageant]], where the [[Nash equilibrium]] results in candidates being chosen completely at random. However, naively strategic voters (i.e. [[Bounded rationality|boundedly rational]] voters) will often elect the worst candidate, analogously to the behavior in the "[[Guess 2/3 of the average|2/3 of the average]]" game.
