[EM] IRV vs Plurality (Dave Ketchum)

[Dave Ketchum]

On Jan 15, 2010, at 10:51 PM, Kathy Dopp wrote:
>> Message: 3
>> Date: Fri, 15 Jan 2010 22:05:58 -0500
>> From: Dave Ketchum <davek at clarityconnect.com>
>> To: Juho <juho4880 at yahoo.co.uk>
>>
>> On Jan 15, 2010, at 7:46 PM, Juho wrote:
>>> On Jan 14, 2010, at 2:13 AM, Dave Ketchum wrote:
>>>> On Jan 13, 2010, at 4:49 AM, Juho wrote:
>>>>> On Jan 13, 2010, at 9:14 AM, robert bristow-johnson wrote:
>>>>>
>>>>>> it still is a curiosity to me how, historically, some leaders and
>>>>>> proponents of election reform thunked up the idea to have a
>>>>>> ranked-order ballot and then took that good idea and married it
>>>>>> to the IRV protocol.  with the 200 year old Condorcet idea in
>>>>>> existence, why would they do that?
>>>>>
>>>>> 1) The basic idea of IRV is in some sense natural. It is like a
>>>>> street fight. The weakest players are regularly kicked out and
>>>>> they must give up. I'm not saying that this would lead to good
>>>>> results but at least this game is understandable to most people.
>>>>> Condorcet on the other hand is more like a mathematical equation,
>
> Yet Condorcet is simple to count and precinct-summable, monotonic, and
> treats all voters' votes equally, unlike IRV/STV which is virtually
> impossible to manually count, requires a mind-boggling number of piles
> and subpiles to count it and requires that all late-counted ballots
> are ready to count centrally, or the entire long tedious process has
> to be restarted.
>
>>>>> and the details of the most complex Condorcet variants may be too
>>>>> much for most voters. Here I'm not saying that each voter (and not
>>>>> even each legislator) should understand all the details of their
>>>>> voting system. The basic Condorcet winner rule is however a simple
>>>>> enough principle to be explained to all. But it may be that IRV is
>>>>> easier to market (to the legislators and voters) from this point
>>>>> of view.
>
> The organization promoting IRV/STV is very well-funded and invests a
> lot of capital into highly misleading local advertising campaigns in
> order to promote its adoption.  I could send this list some
> information on that if anyone is interested.  I don't think that any
> group promoting a fair, equitable, auditable alternative method like
> Condorcet or others has put forth such a well-funded campaign have
> they?
>>>>
>>>> When there is a CW in Condorcet, the CW has won in comparison with
>>>> each other candidate.  While a few may like X or Z enough better to
>>>> have given such top ranking, the fact that all the voters together
>>>> prefer the CW over each other should count, and does with  
>>>> Condorcet.
>>>>
>>>> Else there is a cycle in Condorcet.  Perhaps the following Minimum
>>>> Margins Method Condorcet variant should be used to establish
>>>> Condorcet's preferability over other methods.  Then let other
>>>> variants compete with this one before finally deciding which to  
>>>> use.
>>>>
>>>> Minimum Margins Method:  Consider the cycle, such as A>B>C>A, and
>>>> the margins that create it, such as 60A>30B, 40B>20C, 21C>20A.
>>>> Delete the weakest margins as many times as needed to destroy the
>>>> cycle - in this case A becoming the CW (note that if one C>A voter
>>>> had voted A>C in  this election, A would have become CW with no
>>>> cycle).
>
> Great idea. Is this Dave Ketchum speaking above?  Very simple and
> logically coherent plan.  Thanks for sharing.  Could it be possible
> that this plan would ever not work? (I.e. same margins?)

I did this, though suspecting the idea already has a variant name.   
The adoption is intentionally two steps:
      1.  Use this variant to easily prove there is a Condorcet  
variant ready to compete against such as IRV.
      2.  If there is a better variant, even though likely more  
complex, let it compete against this one.

Same margins is a possibility requiring a response be attended to  
before actual use.  At proposal time the possibility needs mentioning  
- I see nothing more needed at that time (probably delete them one at  
a time in some specified order).
>
>>>
>>> When I see this kind of scenarios I'm always tempted to ask the
>>> question if it is necessary to limit the scope to the top cycle
>>> members or if one can allow also the others win (when the cyclic
>>> opinions in the top cycle are strong). I find also that approach to
>>> be a working solution for many election types (although many have
>>> indicated that they disagree with this).
>>>
>> Note that this method breaks the cycle at the point where the  
>> smallest
>> number of ballots being voted differently would have broken the  
>> cycle.
>>
>> Note that weaker candidates are unlikely to get enough votes to be
>> part of a cycle - being weak they get few high rank votes.
>
> Yes, one could certainly say that this allows the top cycle to prevail
> by breaking the weakest link where weakest is defined as the smallest
> margin in this case.  This minimum margins method is so logically
> correct and fair.
>>>>>
>>>>> 2) IRV is easier to count manually. Condorcet gets quite tedious
>
> Whomever said this obviously hasn't ever counted any IRV or STV
> elections manually in a contest with a substantial number of
> candidates and voters.  Condorcet is orders of magnitude simpler to
> count than is IRV because there can never be more than n x n tallies
> to tally in each precinct and those tallies are precinct-summable,
> whereas IRV requires tallying
>
> n*(n-1)*(n-2) + n(n-1) +n tallies for each precinct even if the voter
> is only allowed to rank three choices - a huge number of tallies as
> the number of candidates grows large and a much larger amount as the
> number of allowed rankings goes up - for each precinct, at least if
> the method is made precinct-summable rather than using a huge number
> of sorting piles which I haven't yet derived the formulas for and have
> no plans to do so.
>
> The reason it takes cities over a month to manually count IRV/STV
> elections in large cities in practice when they don't have computer
> equipment attests to its utter complexity when trying to accurately
> count it manually.  A little test would be to create a semi-complex
> election contest and use say, even just half of the possible
> permutations that IRV/STV can produce and see how many test subjects
> can figure out how to accurately manually count the votes.  The only
> reason it didn't take Minneapolis that long was because the voter
> turnout in Minneapolis' first IRV/STV election was astronomically
> depressed (low) and the incumbant winning candidates had a majority of
> first choice votes so it was won by a simple plurality count.
>
>>>>> to count manually when the number of candidates and voters goes
>>>>> up. One can use some tricks and shortcuts to speed up manual
>
> Condorcet is SO much easier and quicker and simpler to count than IRV
> if one simply tallies one n x n matrix for each precinct and sums the
> corresponding positions for all the precincts.  No need to wait for
> all the absentee and provisional ballots, no need for centralized
> counting, no need to sort and resort ballots into dozens of piles of
> ballots, or even worse with STV keep track of which portion of which
> ballot goes into which pile (tearing or cutting up the ballots would
> help in that manual counting nightmare.)
>
>>>>> Condorcet counting but IRV probably still beats it from this point
>>>>> of view. Manual counting was the only way to count for a long
>>>>> time. Nowadays we have computers and Condorcet tabulation should
>>>>> thus be no problem at all (at least in places where computers are
>>>>> available). But this is one reason why IRV has taken an early  
>>>>> lead.
>>>>
>>>> When an election district has only one polling place, life is  
>>>> simple.
>
> Yes. Another point against IRV/STV is no scalability of manual
> counting. Condorcet is infinitely scalable since it is as simple to
> manually count dozens or hundreds of precincts as it is to count one,
> without moving all the ballots to one central location.
>>>>
>>>> When the district is a state or city, life is more complex for each
>>>> method.
>
> For IRV/STV, but not for precinct-summable methods like Condorcet or
> all the various other precinct-summable methods.
>
> Imagine sending all your ballots nationwide to DC for manual counting
> to check the outcome of a Presidential election. We'll simply let the
> GW administration, for instance, count the results in his own IRV
> election!

This paragraph has inspired comment.  It needs a method willing and  
able to count this correctly - AND able to prove it does that.

Dave Ketchum
>
> Truly, I cannot imagine a more insane method of counting rank choice
> ballots than IRV/STV when one begins to consider the practicalities of
> election administration.
>
> That minimum margin idea for resolving Condorcet cycles is neat, if
> one wants to use rank choice ballots.
> -- 
> Kathy Dopp