[EM] "STAR voting..." paper by Wolk, Quinn & Ogren

[C.Benham]

Quoting from the paper:

> Two criteria which are both highly regarded but are inversely 
> correlated are Favorite Betrayal and Later No Harm

Later-no-Harm is not especially "highly regarded" by me.  It encourages 
the expression of preferences that may not be serious and/or are just
honouring unprincipled preference-swap deals. But at least Hare (aka 
IRV, aka the Alternative Vote, now promoted in the US as RCV) also meets 
Later-no-Help, so there is no crazy
random-fill incentive.

If "inversely correlated" is supposed to mean that the two criteria are 
incompatible, then that is false.  MinMax Pairwise Opposition meets both.

https://electowiki.org/wiki/Minimax_Condorcet_method#Variants
> Minmax(pairwise opposition) does not strictly satisfy theCondorcet 
> criterion <https://electowiki.org/wiki/Condorcet_criterion>orSmith 
> criterion <https://electowiki.org/wiki/Smith_set>. It also fails 
> thePlurality criterion 
> <https://electowiki.org/wiki/Plurality_criterion>, and is more 
> indecisive than the other Minmax methods unless combined with a 
> tiebreaking rule.
>
> However, in return it satisfies theLater-no-harm criterion 
> <https://electowiki.org/wiki/Later-no-harm_criterion>, theFavorite 
> Betrayal criterion 
> <https://electowiki.org/wiki/Favorite_Betrayal_criterion>, and in the 
> three-candidate case, theParticipation criterion 
> <https://electowiki.org/wiki/Participation_criterion>, and theChicken 
> Dilemma Criterion <https://electowiki.org/wiki/Chicken_Dilemma_Criterion>.

> As we will show, STAR Voting incentivizes both honest and expressive 
> voting by counting all ballot data given. The scoring round 
> incentivizes voters to give their favorite(s) five stars. The runoff 
> incentives voters to also give intermediate scores because showing 
> honest preference order ensures their full vote will go to the 
> finalist they prefer in the automatic runoff. Compare this with 
> Instant Runoff Voting, which can actually incentivize Favorite 
> Betrayal because, in order to pass Later No Harm, it ignores 
> down-ballot voter preferences which could have been relevant.

I would say that STAR's failure of Favorite Betrayal is quite a lot 
worse than IRV's. Suppose you (as the voter) are sure that your Greater 
Evil will be in the top-2 and that if the other finalist
is your Favorite  then GE will win, but that your lesser-evil Compromise 
has a much better chance of beating GE in the final than your Favorite. 
Then obviously you have an incentive to give
your favourite zero stars to try to keep him/her out of the final.

The scenario in IRV where you get punished for top-ranking your sincere 
favourite I consider to be a bit less likely, and at least in that case 
the voter can still rank Favorite well above bottom.

> Counting the full ballot for some voters while ignoring relevant 
> ballot data for others (as Later No Harm requires) gives voters a 
> false sense of agency, may erode trust in the system and in voting 
> reform in general, and is out of keeping with the spirit of one 
> person, one vote.
>
>
Complete garbage.

With STAR  Push-over strategy is more tempting and much less risky than 
it is with IRV.   Suppose you are sure that your favourite (or at least 
a candidate you find acceptable) will make
the final but are fearful that the other finalist will be able to 
pairwise beat that candidate.

In that case you obviously have incentive to give at least 4 stars to 
all the candidates you think would pairwise lose to the candidate you like.

And what is supposed to be the excuse for failing Condorcet?

Let me suggest some good methods that use the same ballot information as 
STAR.

Smith//Approval (more than 1 star)

Condorcet//Approval (more than 1 star)

Smith//Approval (above average rating of Smith-set members)

Approval (above average rating of remaining candidates) Elimination

The last two might be too complicated and the last one probably fails 
mono-raise, but they are all vastly better than the nightmare festival 
of Push-over and Compromise
that is STAR.

Chris Benham



>
>
> *Toby Pereira*tdp201b at yahoo.co.uk 
> <mailto:election-methods%40lists.electorama.com?Subject=Re%3A%20%5BEM%5D%20%22STAR%20voting...%22%20paper%20by%20Wolk%2C%20Quinn%20%26%20Ogren&In-Reply-To=%3C1752916145.11797420.1704300809944%40mail.yahoo.com%3E>
> /Wed Jan 3 08:53:29 PST 2024/
>
>
> ------------------------------------------------------------------------
>   Thank you for posting this. A few things jump out to me.
> They briefly discuss the advantages, but the 0 to 5 scoring does still seem fairly limited. They say that it conveys more information than a ranked ballot, but that's not something they've given an objective measure for. You can make a distinction between fewer candidates on a STAR ballot than on a ranked ballot, but you can indicate strength of preference. Amongst that, what's the measure of amount of information? Rob - you mention about whether rating is more intuitive than ranking. My general understanding is that for a small number of candidates, it's easier to rank, but for a large number it's easier to rate, as you just have to have a general opinion of each one rather than an exact pecking order of them all.
>
> On pass/fail criteria, it's interesting that they consider the Equality criterion (where it should be possible to exactly cancel out a vote with an opposite one) to be one that should be passed completely, while generally saying that it's more about not failing any criterion badly. But also, some criteria are easier to pass than others. So by using this reasoning it's easy to hide behind quite a bad criterion failure. E.g., passing participation limits your options for voting methods, whereas I consider independence of clones to be a lot "cheaper". STAR fails independence of clones. In general, I'm not sure a method has to give much up to pass independence of clones.
>
> And this also brings me to my next point - the simulation model. The voting method can change which candidates choose to stand, but I don't think this is modelled by them. STAR's clone failure could cause parties/factions to field two candidates in an attempt to  lock out the run-off.
>
> I wouldn't call myself anti-STAR, but I'm not completely convinced by it as a method.
> Toby
>
>      On Friday, 29 December 2023 at 21:20:24 GMT, Rob Lanphier <roblan at gmail.com  <http://lists.electorama.com/listinfo.cgi/election-methods-electorama.com>> wrote:  
>   
>   Hi everyone,
> There's a paper regarding STAR voting that was recently made "open access":
> https://doi.org/10.1007/s10602-022-09389-3
>
>
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