[EM] Upper-Bucklin naming (was: Median systems, branding....)

[Andy Jennings]

It does sound like this system will have better resistance to the Chicken
Dilemma.  I can support it, assuming noone finds any fatal flaws.

I've thought about the top-down vs. bottom-up question and the naming for a
while and can't form a strong opinion.  Let me think about it some more.

I heard that a big reason FairVote has been moving to the "ranked choice"
branding is that it fits better with their long-term strategy, STV.

~ Andy



On Fri, Jun 14, 2013 at 5:52 PM, Jameson Quinn <jameson.quinn at gmail.com>wrote:

> So. Abd and I now agree that a Bucklin system which uses just the
> above-median votes to break ties is probably the best first step towards
> median voting. I'd like to get the details worked out, so we can stop using
> different terms ("Bucklin", "MJ", "GMJ") and settle on a single
> clearly-defined proposal. I'd love to hear what others feel about these
> issues (though this isn't really the place for debating whether some other
> class of voting system, such as Score or Condorcet or whatever, is better
> or worse than Bucklin/Median systems in general).
>
> 1. How to best express the system? Two equivalent definitions:
>
>    - *Top-down*: "Count the votes at the highest grade for each
>    candidate. If any one candidate has a majority, they win. If not, add in
>    lower grades, one at a time, until some candidate or candidates get a
>    majority. If two candidates would reach a majority at the same grade level,
>    then whichever has the most votes above that level wins. If there are no
>    votes above that level, the highest votes at or above that level wins."
>    - *Bottom-up*: "Count the votes at the lowest grade against each
>    candidate. If any candidates have a majority against, eliminate them from
>    consideration. Continue adding in the next-lowest grade, until there is
>    just one or zero candidates left. If there's one left, they win. Otherwise,
>    if the last few candidates are eliminated together, choose whichever of
>    that group was eliminated by the smallest majority against."
>
>
> 2. How many rating/grade/rank levels should be used, and how should they
> be labeled? I'd suggest the following 5, along the lines of something Abd
> proposed:
>
> A: Unequivocal support
> B: Probable support (unless there's a candidate with majority "A" support)
> C: Neutral (support or oppose, depending on other candidates' results)
> D: Probable opposition (unless all other candidates have majority "F"
> opposition)
> F: Unequivocal opposition
>
> (I've relabeled the categories to help clarify their strategic meaning;
> for instance, I changed "strong" to "unequivocal")
>
> I would also be open to having blank votes count as "E" rather than "F",
> but I think that's probably an unnecessary complication to begin with.
>
> 3. What should we call this system? Abd seemed happy with "Instant Runoff
> Approval Voting". I'd be fine with that too, but before we settle on that,
> we should look at the downsides:
>
>    - FairVote has been moving away from "Instant Runoff / IRV" and
>    towards "ranked choice/ RCV" in recent years. I don't know all of their
>    reasons, but I suspect it is partially to do with the legalism of ballot
>    initiative language. That is, IRV is technically neither instant nor a
>    runoff, though it is certainly close on both counts.
>    - It could lead to confusion between IRAV and IRV. That has its
>    upsides — piggybacking on FairVote's existing publicity — but also its
>    downsides — as we know, IRV is actually a pretty flawed system.
>
> So I think we should have a poll with various options (using the system
> itself to rate the options, of course). I'll start out with some proposals
> and my votes:
>
> -IRAV: B
> -Descending Approval Threshold (DAT) Voting: A
> -Descending Approval Threshold Adjudgment (DATA voting): B
> -Majority Approval Threshold (MAT; note that the M could also be
> backronymmed to "Median"): A
> -Bucklin: F (not that we shouldn't say that this system is a Bucklin
> system, just that that shouldn't be our only name for it)
> -Bucklin-ER or ER-Bucklin: D (has already been used for other systems, not
> a descriptive name)
> -Graded Approval Threshold (GAT): C (Not bad, but not great)
> -Majority Assignment of Grades (MAG): C (ditto)
> -Graded Majority Approval (GMA): B (this one seems simple and descriptive)
>
> Note that all of the above names could, in principle, apply to almost any
> Bucklin system; but whichever one we pick, we'll arbitrarily define it as
> being this system in particular.
>
> Abd and anyone else who has an opinion: please vote among the above
> options.
>
> Jameson
>
>
> 2013/6/13 Abd ul-Rahman Lomax <abd at lomaxdesign.com>
>
>> At 03:53 PM 6/13/2013, you wrote:
>>
>>> I just had a minor realization. As I said to Abd, his Bucklin-ER (as I
>>> understand it) has slightly less resistance to the chicken dilemma than
>>> GMJ, because the Bucklin-ER tiebreaker effectively ends up focusing
>>> slightly below the median in the grade distribution, while GMJ focuses on a
>>> region balanced around the median. Well, why not take that in the other
>>> direction? Consider the following Bucklin system, tentativlely named:Â
>>> uı|ʞɔnq-ᴚƎ:
>>>
>>>
>>> Count the votes at the highest grade for each candidate. If any one
>>> candidate has a majority, they win. If not, add in lower grades, one at a
>>> time, until some candidate or candidates get a majority. If two candidates
>>> would reach a majority at the same grade level, then whichever has the most
>>> votes above that level wins. If there are no votes above that level, the
>>> highest votes at or above that level wins.
>>>
>>
>> Now, this is familiar to me. I'm not searching right now, but I do think
>> that this may have been a tiebreaker method with traditional Bucklin.
>>
>> Here, what it does is to award a win based on a plurality in the prior
>> rank, but with the approval of a majority as shown by the next rank of
>> approvals. Way cool. It incentivizes expressing preferences with some
>> strength. If candidate count increases to that the limitation to three or
>> four ranks is a problem, the number of ranks (ratings) may be increased.
>>
>>  Now consider a chicken dilemma where Y and Z must cooperate to defeat X.
>>> If a Y voter rates Z at the second-to-bottom grade, then further strategy
>>> simply will not help unless Z's median falls to 0 — which would mean
>>> risking ann X win if Z's voters are similarly strategic. This is a
>>> stronger, and more-simply-argued, bulwark against the chicken dilemma's
>>> slippery slope than GMJ's.
>>>
>>
>> Indeed it is simpler, which is a powerful argument for it. You don't even
>> have to mention "median."
>>
>> It *does have a problem*, which may show up in simulations. I'd prefer
>> this method if completion in a single round is being insisted on. I'd want
>> to see if the previous round winner and the plurality winner in the next
>> round agree. If they do, easily, done. If not, then it could be time for a
>> runoff.
>>
>> As stated, the method is not Condorcet compliant. In a runoff system or
>> if the completion in the first round requires coincidence of the plurality
>> winner at both ranks, I suspect it is Condorcet compliant *as to the
>> evaluated ranks.* It's simple to extend that by using pairwise analysis on
>> all the ranks.
>>
>>  GMJ still has certain advantages. Because it's cleaner and more
>>> symmetrical in an abstract sense, its criterion compliances are slightly
>>> better; and uı|ʞɔnq-ᴚƎ does not allow reporting via 1 number per
>>> candidate. But these are minor, technical points. While I still have a
>>> father's affection for GMJ, I think that uı|ʞɔnq-ᴚƎ is now my
>>> favorite system.
>>>
>>
>> It could be quite good. I'd want to see simulation analysis of it by
>> comparison with other methods.
>>
>>
>>  Obviously the name needs fixing; I've left it with a deliberately
>>> unusable one for now. I'd be happy to call it IRAV, or APV, or whatever
>>> other people support in this thread.
>>>
>>
>> It's a Bucklin method! It merely deals with the issue of multiple
>> majorities. As I've written, we should be so lucky as to have those. What
>> this would do is to encourage, relatively, additional approvals at the
>> lower rank. It is an additional LnH protection.
>>
>> Bucklin-ER/MMP? Multiple Majority Protection.
>>
>> Multiple Majorities occur because the majority is a bit over-eager to
>> compromise. This method backs up if a multiple majority occurs. By doing
>> so, it makes the so-called "chicken dilemma" less of a dilemma. The chicken
>> dilemma is a fear of LnH failure. Do I vote for a compromise or do I
>> continue to stand for my Favorite(s)?
>>
>> To make this more obvious and more *accurate*, consider the use of more
>> ranks. With more approved ranks, a multiple majority becomes less likely,
>> and a majority is cleanly found, more often. This, then, is a method of
>> handling the rarer multiple majorities.
>>
>> And, did we mention, it is *easy to explain*?
>>
>> *Somebody* has been listening to my rantings.
>>
>> Thanks, Jameson. Great work.
>>
>
>
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