[EM] Upper-Bucklin naming (was: Median systems, branding....)
Andy Jennings
elections at jenningsstory.com
Sat Jun 15 16:08:06 PDT 2013
I also report that I was talking with a progressive activist (and former
legislator) here in Arizona last year who didn't like branding of the word
"majority". He was afraid it would be a turn-off to those who feel like
the wrong majority is already too dominant.
~ Andy
On Sat, Jun 15, 2013 at 3:38 PM, Andy Jennings
<elections at jenningsstory.com>wrote:
> 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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>
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