[EM] Fwd: Election-Methods Digest, Vol 236, Issue 18

[Closed Limelike Curves]

*Only if there is a cycle involved.  Either the election was in a cycle in
the first place or if the burial strategy is to push the election into a
cycle.If there never ever were any cycles, then Condorcet does not fail.*

This is like saying that if there never were any odd numbers, 3 would be an
even number. If Condorcet cycles were mathematically impossible, that would
be great. Sadly, they aren't, so we have to deal with them.

For strategy, the mathematical *possibility* of a cycle--not its actual
occurrence in a set of results--is what matters, because threatening to
create a cycle is what forces a Condorcet winner's supporters to vote
strategically.

The system you're proposing--where we make cycles impossible--is Borda, not
Condorcet. Saari shows that if you delete every subset of ballots that
forms a cycle, then elect the Condorcet winner, you get Borda. If Condorcet
is "strategyproof unless cycles are involved," then Borda is *always*
strategy proof, because it's got none of them--but clearly it's not, and
the reason why is because what matters is whether you *could*,
hypothetically, have a cycle, not whether you actually *do*.

In reality, cycles are always involved. Sometimes it's a real cycle.
Sometimes it's a theoretical cycle that someone *could* create, and that
threat gives them leverage.

On Sun, Mar 17, 2024 at 1:06 PM robert bristow-johnson <
rbj at audioimagination.com> wrote:

>
>
> > On 03/16/2024 9:11 PM EDT Closed Limelike Curves <
> closed.limelike.curves at gmail.com> wrote:
> >
> >
> > > We don't wanna burden voters with any pressure to vote tactically, do
> we? Why are people (equal.vote (http://equal.vote/), CES) promoting
> methods that, whenever there are 3 or more candidates, **inherently**
> forces voters to make tactical consideration of how they're going to vote
> for their 2nd-favorite candidate?
> > Every method does this. With 3 candidates all Condorcet methods can
> encourage burial.
>
> Only if there is a cycle involved.  Either the election was in a cycle in
> the first place or if the burial strategy is to push the election into a
> cycle.
>
> If there never ever were any cycles, then Condorcet does not fail.  No
> spoiler, no incentive to vote other than sincerely.  If you (the voter)
> lose, it's because you're in the minority.  If your hated candidate wins,
> it's because no other candidate is favored by more voters than this hated
> candidate.
>
> > > BTW, I posted at r/EndFPTP a derived scenario that shows how STAR
> fails to disincentivize tactical voting, even with the head-to-head runoff.
> https://www.reddit.com/r/EndFPTP/comments/1bbq6hu/heres_a_good_hypothetical_for_how_star_fails/
> > I don't see how that's a failure. There's two possibilities here:
> > 1. If the votes are honest, I don't see what the problem is. The three
> candidates are neck-and-neck and there's not much reason to prefer any.
>
> The Center candidate is the Condorcet Winner and STAR *only* compares
> relative *rankings* in the runoff.  So like IRV, if the Condorcet Winner
> gets into the final runoff, the Condorcet Winner will always beat anyone
> else there.
>
> The voters supporting Center but who liked Left better than Right would
> have done better (like get their candidate elected) by burying Left.  (But
> at least 6 of them, had 4 of them buried Left, they would cause Right to
> win.)  So, by even by scoring Left at merely 1, they actually betrayed
> their favorite candidate.
>
> The voters supporting Right and who liked Center better than Left (this
> would be normal) would have done better (like preventing Left from winning)
> by scoring Center a little higher than they did.  Had 2 or 3 or 6 of them
> scored Center higher, enough for 6 points, then Left would be defeated.
> But then they have to betray their favorite candidate and the promise of
> STAR is that you don't have to do that.  Now, what was hard for the Right
> voters in Burlington to accept was that their candidate was never going to
> win in *any* pairwise comparison and that their candidate was the spoiler.
> But that was actually the case.  Alaska was a little different.  Peltola
> was always in the lead and there was no "come from behind" victory as
> occasionally happens with IRV.
>
> > 2. If the votes are strategic, this seems like terrible strategy on the
> part of each group.
>
> NO VOTER should have to strategize.  But I explained that if your
> preference is A>B>C, why without sophisticated consideration of the
> possibilities it makes perfect sense to score your ballot A:5, B:1, C:0.
> Makes simple sense, particularly with STAR (and assuming only 3 significant
> candidates).  The problem is when it's a close 3-way race, then, whether
> it's STAR or IRV, then tactical voting might serve a voter's political
> interests better than sincere voting.  We should prevent that burden of
> tactical voting whenever we can.  (And we can with the ranked ballot as
> long as there is always a Condorcet Winner.)
>
> > Why wouldn't you give the center candidate more than 0 stars?
>
> I modeled this after real votes in Burlington 2009.  There were 1289 Right
> voters (outa 3294) that bullet-voted for Right.  There were even 568 Left
> voters (outa 2981) that bullet-voted for Left.  That's what they did.
>
> Now, unlike STAR, IRV would not have helped the Center voters with any
> burying strategy.  The problem with both STAR or IRV is with the Right
> voters who were told that they can throw their full support behind Right
> and not get burned by it.  That was clearly not true in Burlington 2009 nor
> in Alaska 2022 with IRV and I don't think STAR would have done better.
>
> --
>
> r b-j . _ . _ . _ . _ rbj at audioimagination.com
>
> "Imagination is more important than knowledge."
>
> .
> .
> .
>
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