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{{cleanup|reason=This article is written like a personal reflection, personal essay, or argumentative essay that states an editor's personal feelings or presents an original argument about a topic.}}
 
'''Symmetrical ICT''', short for '''Symmetrical Improved Condorcet, Top''' is a voting method designed by Michael Ossipoff. <!-- when? link to EM? --> It is based on Kevin Venzke's concept of "Improved Condorcet", which is a modification of pairwise comparison logic that enables methods to pass the [[favorite betrayal criterion]] at the cost of sometimes failing the [[Condorcet criterion]].
 
==Definition==
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# If only one candidate is unbeaten, then s/he wins.
# If everyone or no one is unbeaten, then the winner is the candidate ranked in 1stfirst place on the most ballots.
# If some, but not all, candidates are unbeaten, then the winner is the unbeaten candidate ranked in 1stfirst place on the most ballots.
 
== Improved Condorcet ==
 
Condorcet methods usually have a low but nonzero rate of [[favorite betrayal]] failures. <!ref>{{cite web|url=http://lists.electorama.com/pipermail/election-methods-electorama.com/2005-June/114476.html|title=Measuring refthe EMrisk postof strict ranking|website=Election-methods mailing list archives|date=2005-06-28|last=Venzke|first=K.}}</ref> '''Improved Condorcet''' is a modification of pairwise comparisons in an otherwise Condorcet-compliant method to turn absolute Conrocet compliance and a low rate of [[FBC]] failure into absolute FBC compliance and a low rate of [[Condorcet criterion]] failures.
 
Mike Ossipoff argued that improved Condorcet allows a voter who wants one of X and Y to win, and who ranks X first, to change a ranking of X>Y into X=Y without undue risk that this will change the winner from Y to someone lower ranked by that voter; and thus that it's better to satisfy the IC version of Condorcet than the actual [[Condorcet criterion]].
 
==History==
 
ICTThe stands for "Improvedtied-Condorcetat-Top".the-top Therule idea forand Improved Condorcet isideas fromwere devised by Kevin Venzke. Improvedin Condorcetan meetseffort to create a [[Minmax]] variant that passes the [[FBC]]. Then, later, Chris Benham proposed completion by top-count, to achieve "defection-resistance", avoidance ofavoid the [[chicken dilemma]]. Chrisand hadthus aachieve longdefection-resistance.<ref>{{cite nameweb|url=http://lists.electorama.com/pipermail/election-methods-electorama.com/2012-January/094905.html|title=TTPBA//TR for(a his3-slot method,ABE butsolution)|website=Election-methods Imailing calledlist it "Improvedarchives|date=2012-Condorcet01-Top",13|last=Benham|first=C.}}</ref> inMike keepingOssipoff withshortened Kevin'sthe namingname of this method to "Improved Condordet, Top".
 
Mike later proposed that the ICT tied-at-the-top rule also be applied to the bottom end, to almost achieve [[later-no-help]] compliance, which then led to Symmetrical ICT.
 
==Criterion compliances==
 
Symmetrical ICT passes the [[favorite betrayal criterion]] and the [[chicken dilemma criterion]]. It fails the [[Condorcet criterion]].
I later proposed that the Improved Condorcet improvement be done at bottom-end as well, to almost achieve compliance with Later-No-Help, which would achieve additional easing and simplification of strategy need.
 
==Notes==
But the big improvements were those of Kevin and Chris.
 
If you leave outOmitting the + (X=Y)B term, thenwould you'llturn havethis method into ordinary ICT. OrdinaryIn Mike's opinion, ordinary ICT has the most important properties of Symmetrical ICT., but Symmetrical ICT merely adds a somewhat less important improvement, consisting of simpler bottom-end strategy.▼
I call my version Symmetrical ICT.
 
In an election with dichotomous preferences, the best ICT strategy is Approval strategy: equal-rank all approved candidates first and all unapproved candidates last.
 
----
<!-- Start of Michael's original article/essay -->
 
After the description and definition of Symmetrical ICT, I'll say a few words of what it implies for the compatibility of FBC and Condorcet's Criterion.
 
----
 
▲If you leave out the + (X=Y)B term, then you'll have ordinary ICT. Ordinary ICT has the most important properties of Symmetrical ICT. Symmetrical ICT merely adds a somewhat less important improvement, consisting of simpler bottom-end strategy.
 
Justifications for ICT and Symmetrical ICT:
 
One justification is that they gain compliance with [[FBC]].
 
Another is that they automatically avoid the chicken dilemma, meeting the [[Chicken Dilemma Criterion]].
 
Additionally, suppose that you rank two candidates, X and Y in 1st place. You rank them in 1st place because you'd prefer that they win, instead of the other candidates.
 
Now, suppose that candidate X would beat everyone, and thereby win, except that then you (and a few other same-voting people) move Y up to 1st place too. Previously X beat Y. But now, because you people have moved Y to 1st place with X, you've removed some X>Y votes, and so now Y beats X. And now, instead of someone beating everyone, there's a top-cycle in which Z (the worst candidate) is a member (becaues Z beats X). And, by whatever circular tiebreaker is used, Z wins.
 
Did you want that to happen? When you ranked X and Y in 1st place, did you mean that you wanted your last choice to win? No, you primarily wanted X or Y to win. Well then, what if, for the purpose of the X/Y pairwise comparison, you could cast a custom-made, adjustable, vote to achieve the result that you prefer, to protect the win of someone in {X,Y}. You don't want X or Y to beat eachother, because, as seen above, that could make neither of them win, and give the win to someone much worse. So you'd X prefer to use that vote for the purpose of voting against either candidate beating the other. For instance, if Y would otherwise beat X, then you'd cast an X>Y vote, your vote against one beating the other. You'd do that to avoid the possibility of the sceraio described above, because you prefer that X or Y win.
 
So then, what if we say that, when ranking X and Y in 1st place, in addition to counting as pairwise votes for them over everyone else, it also counts as a vote, by you, against either beating the other. That would be the way to interpret your equal top ranking in a way that is consistent with your interest, preferences, intent and wishes.
 
That doesn't give you more voting power. It just allows you to use ''your'' vote in your best interest, consistent with your preferences, intent and wishes. It's your vote, you know.
 
That's Improved Condorcet.
 
Now, traditionally, for the purpose of the Condorcet Criterion, we say that X beats Y iff more people rank X over Y than Y over X. But, as I said, the above-described Improved Condorcet interpretation of equal top ranking is the interpretation that is more in keeping with the interest, preferences, intent and wishes of the voter who votes that equal top ranking. In other words, it has more legimacy than the traditional interpretation, and the traditional definition of "beats", quoted at the beginning of this paragraph.
 
And, since it has more legitimacy, it would be a better choice, when deciding who beats whom, for the purpose of the Condorcet Criterion.
That results in a more legitimate Condorcet Criterion.
 
And when that interpretation and counting of equal top rankings is used for the purpose of the Condorcet Criterion, Improved-Condorcet meets Condorcet's Criterion.
 
Maybe someone will say, Yeah, you make Improved-Condorcet meet the Condorcet Criterion by modifying Condorcet's Criterion to match Improved Condorcet. But note that I told why the Improved Condorcet interpretation of equal top ranking is more in keeping with the interest, prefereces, intent and wishes of the equal top ranking voter, and therefore is more legitimate. It'a a matter of using a more legitimate interpretation, rather than just modifying a criterion to match a method.
 
Besides, the reason why the method uses that interpretation is likewise because it's more legitimate, and what the equal top ranking voter prefers.
 
And that genuine legitimacy is the reason why Symmetrical ICT meets [[FBC]] (unlike traditional unimproved Condorcet).
 
So: Improved Condorcet versions, including ICT and Symmetrical ICT, meet the Condorcet Criterion, when it is defined more legitmately.
 
Likewise, then, it can be said that FBC and the Condorcet Criterion are compatible, contrary to popular belief.
 
Symmetrical ICT, like ordinary ICT, automatically avoids the chicken dilemma.
 
'''A few improved properties of ICT and Symmetrical ICT:'''
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Michael Ossipoff
 
==References==
 
[[Category:Ranked voting methods]]
Kristomun
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