Center squeeze: Difference between revisions
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The '''center squeeze effect''' refers to a class of voting scenarios
Many consider that the Condorcet winner (the candidate that would beat any other candidate in a head-to-head election) or utilitarian winner (the candidate rated most highly by the electorate) is the rightful winner of an election. Failing to select this candidate can encourage strategy
Note, however, that methods avoiding center squeeze can also incentivize strategy if one of the wings thinks they can squeeze out victory for their preferred candidate by concealing their support for the center. [[Bullet vote|Bullet voting]] in [[approval voting]] is an example of this; see [[Chicken dilemma]] for more information.
Voting systems that suffer from the center-squeeze effect exhibit a bias in favor of more extreme candidates, which leads to unrepresentative winners and political polarization.<ref name=":3">{{Cite book|url=https://link.springer.com/10.1007/978-3-642-02839-7|title=Handbook on Approval Voting|date=2010|publisher=Springer Berlin Heidelberg|isbn=978-3-642-02838-0|editor-last=Laslier|editor-first=Jean-François|series=Studies in Choice and Welfare|location=Berlin, Heidelberg|pages=2|language=en|doi=10.1007/978-3-642-02839-7|quote=By eliminating the squeezing effect, Approval Voting would encourage the election of consensual candidates. The squeezing effect is typically observed in multiparty elections with a runoff. The runoff tends to prevent extremist candidates from winning, but a centrist candidate who would win any pairwise runoff (the “Condorcet winner”) is also often “squeezed” between the left-wing and the right-wing candidates and so eliminated in the first round.|editor-last2=Sanver|editor-first2=M. Remzi}}</ref><ref name=":4">{{Cite web|url=https://thehill.com/opinion/campaign/3711206-the-flaw-in-ranked-choice-voting-rewarding-extremists/|title=The flaw in ranked-choice voting: rewarding extremists|last=Atkinson|first=Nathan|last2=Ganz|first2=Scott C.|date=2022-10-30|website=The Hill|language=en-US|access-date=2023-05-14|quote=However, ranked-choice voting makes it more difficult to elect moderate candidates when the electorate is polarized. For example, in a three-person race, the moderate candidate may be preferred to each of the more extreme candidates by a majority of voters. However, voters with far-left and far-right views will rank the candidate in second place rather than in first place. Since ranked-choice voting counts only the number of first-choice votes (among the remaining candidates), the moderate candidate would be eliminated in the first round, leaving one of the extreme candidates to be declared the winner.}}</ref>
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On a 2-dimensional political compass with 3 candidates, candidate B is the Condorcet winner and utilitarian winner, but is squeezed out by A and C on either side:
[[File:2D election example A vs B vs C.png]]
<!--{{Graph:Chart|width=200|height=150▼
|xAxisTitle=Candidates|yAxisTitle=Votes|type=rect
|x=A, B, C
|y=1031, 861, 1108
|colors=#1f77b4, #ff7f0e, #2ca02c
}}-->
[[File:Center Squeeze (before).svg|frameless]]
C would win under a single-round of FPTP, but if there is a runoff, then more of B's votes transfer to A, making A the winner:
[[File:2D election example A vs C.png]]
<!--{{Graph:Chart|width=200|height=150
▲{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes|type=rect
|x=A, B, C
|y=1619, 0, 1381
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
[[File:Center Squeeze (after).svg|frameless]]
Either way, the winner is not as good of a representative of the electorate as candidate B.
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