[EM] Relative vs. Majority Condorcet

[Closed Limelike Curves]

> The way you describe ICT I find a bit odd.

Yes, I think I made a few mistakes, including confusing ICT with
symmetrical ICT (I have no idea what ICT is, assuming they're different;
electowiki doesn't have an article).


> Kevin's  ICA method easily meets Minimal Defense.  ICT instead meets
> Chicken Dilemma (incompatible with Minimal Defense) but I think I recall
> was motivated by some example where the MCA winner looked quite odd.

Could you clarify how the chicken criterion is incompatible with Minimal
Defense? Intuitively I thought median ratings would do well against both.

On Sun, Apr 28, 2024 at 12:34 PM Chris Benham <cbenhamau at yahoo.com.au>
wrote:

> CLC,
>
>
> Yes, that's the main question I'm looking to answer with this poll: do
> tied-at-the-top, or other tied-rank mechanisms, have substantial support on
> this email list? (ICT is a similar, but not-quite-working, attempt at
> satisfying Minimal Defense as well.)
>
>
> I assume by "mechanisms" you mean  * mechanisms to force the method to
> comply with Favorite Betrayal*.   As far as I can tell, no.
>
> The way you describe ICT I find a bit odd.   Kevin's  ICA method easily
> meets Minimal Defense.  ICT  instead meets Chicken Dilemma (incompatible
> with Minimal Defense) but I think I recall was motivated by some example
> where the MCA winner looked quite odd.
> I don't recall it but can probably find it later.
>
> Chris B.
>
> On 28/04/2024 12:40 pm, Closed Limelike Curves wrote:
>
> Hi Chris, thanks for your response!
>
>  I came to the conclusion that any good more sophisticated FBC methods
>> need to use Kevin's  "Tied at the Top Rule" mechanism.
>>
> Yes, that's the main question I'm looking to answer with this poll: do
> tied-at-the-top, or other tied-rank mechanisms, have substantial support on
> this email list? (ICT is a similar, but not-quite-working, attempt at
> satisfying Minimal Defense as well.)
>
>
>> There is some small movement and enthusiasm for Condorcet compliance, but
>> none that I discern for strict FBC compliance.  I would think most voters
>> would satisfied with the massive reduction in Compromise incentive compared
>> to FPP afforded by properly implemented IRV, let alone the still greater
>> reduction we get from Condorcet.
>>
> There's a major IRV-repeal effort underway in Alaska at the moment because
> they had one (!) election with a favorite-betrayal incentive. I'm also not
> aware of any movements for strict relative-majority Condorcet compliance.
> The organization that comes closest is EVC (with their Copeland//Borda
> proposal), but even they're not very purist about it.
>
> And I'm generally allergic to, and find very silly, methods that fail
>> Irrelevant Ballots Independence like Median Ratings methods and this
>> "Majority-Condorcet" idea.
>
> I fully agree with you that this is a big problem for median ratings. A
> voter who shows up and says they think all the candidates are bad isn't
> provide any new information about the relative quality of the candidates.
>
> However, I don't think an all-equal ballot is providing no information in
> every situation. As an example, say we had a system like approval, but with
> a 50% threshold for election (and elections with <50% support for the
> winner resulting in reopening nominations). Then, a fully-blank ballot is a
> way for voters to meaningfully express their preference for somebody else, other
> than the current crop of candidates.
>
> Something similar applies to the tied-at-the-top rule: a voter who ties
> two candidates is saying they want these two candidates to be compared
> using the tiebreaking mechanism, *rather than* the relative-Condorcet
> mechanism.
>
> On Sat, Apr 27, 2024 at 5:00 AM Chris Benham <cbenhamau at yahoo.com.au>
> wrote:
>
>> There was some advantage of ICA & ICT that I really liked, but public
>> proposals have to be as simple as possible.
>>
>>
>> In that case I say forget about FBC methods other than Approval.   I came
>> to the conclusion that any good more sophisticated FBC methods need to use
>> Kevin's  "Tied at the Top Rule" mechanism.
>>
>> There is some small movement and enthusiasm for Condorcet compliance, but
>> none that I discern for strict FBC compliance.  I would think most voters
>> would satisfied with the massive reduction in Compromise incentive compared
>> to FPP afforded by properly implemented IRV, let alone the still greater
>> reduction we get from Condorcet.
>>
>> In general FBC is much more slippery and "expensive" (in terms of being
>> compatible with other criteria) than Condorcet.  I went off my own
>> "Irrelevant-Ballot Independent Fall-back Approval" idea (which isn't "very
>> simple") when Kevin showed that it fails Woodall's Plurality criterion.
>>
>> And I'm generally allergic to, and find very silly, methods that fail
>> Irrelevant Ballots Independence like Median Ratings methods and this
>> "Majority-Condorcet" idea.
>>
>> You have an apparent "majority Condorcet" winner, and then a few extra
>> ballots that vote for nobody are found and then the winner changes because
>> the "majority" threshold goes up. Absurd and potentially embarrassing.
>>
>> Chris B.
>>
>> On 27/04/2024 3:40 pm, Michael Ossipoff wrote:
>>
>> There was some advantage of ICA & ICT that I really liked, but public
>> proposals have to be as simple as possible. Few methods proposed here are
>> simple enough for public proposal.
>>
>> On Fri, Apr 26, 2024 at 22:50 Michael Ossipoff <email9648742 at gmail.com>
>> wrote:
>>
>>>
>>>
>>> On Wed, Apr 24, 2024 at 10:02 Closed Limelike Curves <
>>> closed.limelike.curves at gmail.com> wrote:
>>>
>>>>
>>>> *Does "Majority-Condorcet" mean the CW needs to have a majority over
>>>> every other candidate?*
>>>>
>>>> Yes: a CW needs more than 50% of the vote, including tied ranks, to
>>>> defeat every other candidate. This version of Condorcet is compatible with
>>>> FBC.
>>>>
>>>
>>> I guess a lot of CWs wouldn’t be getting elected.
>>>
>>> The best Condorcet methods don’t importantly fail FBC. A sincere CW can
>>> only lose by offensive strategy, & the better Condorcet methods well-deter
>>> offensive strategy. No need for any defensive strategy.
>>>
>>> Was it you who once said that people would try offensive strategy? The
>>> whole point of strategy is action based on an analysis of what the result
>>> will be. It’s a strategist’s business to find that out first.
>>>
>>> Anyway when it’s noticed to usually backfire…
>>>
>>>
>>>> On Wed, Apr 24, 2024 at 3:43 AM Kristofer Munsterhjelm <
>>>> km_elmet at t-online.de> wrote:
>>>>
>>>>> On 2024-04-24 12:32, Kevin Venzke wrote:
>>>>>
>>>>> > The second option doesn't offer Smith, but if it did, I would note
>>>>> that Smith is a
>>>>> > poor guarantee of quality. Here's a 1025-voter election where a
>>>>> 2-vote candidate is
>>>>> > in the Smith set (along with all other candidates):
>>>>> >
>>>>> > 2: A>B>C>D>E>F>G>H>I>J>K
>>>>> > 1: B>C>D>E>F>G>H>I>J>K
>>>>> > 2: C>D>E>F>G>H>I>J>K
>>>>> > 4: D>E>F>G>H>I>J>K
>>>>> > 8: E>F>G>H>I>J>K
>>>>> > 16: F>G>H>I>J>K
>>>>> > 32: G>H>I>J>K
>>>>> > 64: H>I>J>K
>>>>> > 128: I>J>K
>>>>> > 256: J>K
>>>>> > 512: K
>>>>> >
>>>>> > While this is not realistic, I do think it is realistic that a
>>>>> candidate of limited
>>>>> > interest to most voters would sometimes manage to pairwise defeat a
>>>>> more viable
>>>>> > candidate. And we should be ready to interpret this as noise.
>>>>>
>>>>> That was phrased a bit oddly in the context of the rest of your post,
>>>>> but I understand you to be saying "the worst method that passes Smith
>>>>> may still be pretty bad", not necessarily that proposed methods
>>>>> passing
>>>>> Smith are actually bad. Is that right?
>>>>>
>>>>> -km
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>>>>>
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