[Election-Methods] RELEASE: Instant Runoff Voting (Chris Benham)

[Juho]

Yes, this was an excellent (clear basic) example as well. The  
introduction of new candidates definitely changes the scoring of the  
candidates by the voters.

One can study also voter specific absolute scoring that never changes  
despite of changes in the candidate list. This is a theoretical  
option that assumes fully sincere ratings based on some absolute  
scale (where each voter has himself/herself frozen 0 and 10 at some  
fixed positions, or alternatively the election organizer has given  
those fixed points, e.g. 0="totally unacceptable", 10="best possible  
person in the world"). The examples assumed normalized Range votes  
(where voters typically use both 0 and 10 in their ballot).

In real life competitive elections normalized votes are of course  
typical (in Range one may also get lots of exaggerated votes where  
voter uses mostly 0 and 10 and seldom any intermediate values), which  
makes the examples much more realistic than the theoretical absolute  
scale approach that I mentioned above.

Juho



On Jun 22, 2008, at 19:35 , Terry Bouricius wrote:

> Ms. Dopp has requested a clearer example of how Range and Approval  
> voting
> can experience a spoiler scenario (through violation of the  
> Independence
> of Irrelevant Alternatives (IIA) Criterion). Although her inability to
> follow Chris's logic led her to use extremely disrespectful  
> language, I
> will assume she was having a bad day and was just extremely  
> frustrated.
>
> Here is a simple example, that I hope she can follow...
>
> How a voter scores a particular candidate (or whether the candidate  
> is on
> the positive or negative side of an approval cut-off) depends on what
> other candidates the voter has to compare the candidate to.
>
> If the voter thinks candidate A is okay, and B is horrible in a two  
> way
> race, the voter will likely score A as a 10 and B as a 0 (approve A  
> and
> not approve B). [Rather than insert an Approval Voting translation for
> each point from here on I will just use a Range example, though the
> dynamic is the same.]
>
> If there are 100 voters and  55 prefer A>B and 45 B>A, this two-way  
> race
> could end with a total score of 550 for A (55 voters giving a 10  
> and 45
> giving a 0) to 450 for B. Thus A is both the de facto majority  
> choice as
> well as the Range score winner.
>
> Now comes the spoiler...What if candidate C decides to run as well? It
> happens that a significant portion (let's say 25 out of the 55) of the
> former A supporters who care most about issue X view candidate C as a
> fantastically superior candidate to A or B (though they still prefer A
> over B as well). It seems likely that many of these voters would  
> feel the
> need to reduce the score of ten they otherwise would give to A to make
> room on the scale so they can indicate how superior C is to A.  
> These 25
> voters might now score the candidates as follows, A=5, B=0, and  
> C=10. In
> other words, the score that A now receives from some voters depends on
> whether C has entered the race. The B supporters who generally  
> don't care
> much about issue X view C as just another version of A, so give  
> this new
> candidate a 0 as well. Under this entirely plausible scenario, with  
> C in
> the race, now the total scores might be A now only gets 425 (30 x  
> 10 and
> 25 x 5), while B still gets 450 (45 x 10) and C gets 250 (25 x 10).
>
> Thus C has "spoiled" the race for A. The entry of C caused B to go  
> from a
> loser to a winner.
>
> The identical dynamic can be demonstrated for Approval Voting using  
> voter
> decisions about where to draw their approval cut-off line, once C  
> enters
> the race.
>
>
> -Terry Bouricius
> terryb at burlingtontelecom.net
> (802) 864-8382
>
>
>
> ----- Original Message -----
> From: "Kathy Dopp" <kathy.dopp at gmail.com>
> To: <election-methods at lists.electorama.com>
> Sent: Saturday, June 21, 2008 8:54 PM
> Subject: Re: [Election-Methods] RELEASE: Instant Runoff Voting (Chris
> Benham)
>
>
> Chris,
>
> You example clearly does not provide an example of approval voting
> being subjected to the spoiler effect.
>
> You managed to invent a really bad voting method (asking voters for
> ratings and then converting their ratings to approval/disapproval by
> your new voting method) and applied your method of conversions to your
> own example, but it has nothing to do with either range or approval
> voting methods.
>
> Chris, This is the LAST time I will take any of my time to respond to
> any of your emails since your emails either lack any logic or show
> that you did not take the time to read and study either Abd ul's email
> rebuttals of Fair Vote or the paper I wrote and I don't have time to
> waste on annoying silliness.
>
> On Sat, Jun 21, 2008 at 5:03 PM,  > Date: Sat, 21 Jun 2008 > Ok.
> Suppose? the method is Approval, there are two candidates (A and B)
> and the voters'
>> utilities (sincere ratings on some fixed scale independent of the
>> candidates) are:
>> 40: A100, B98
>> 25: A98,?? B1
>> 35: B100, A1
>
> OK. Then if this example is counted using approval voting by removing
> the ratings for these voters, there is a TIE since 100% of voters
> approve of both A and B.
>
>>
>> I assume that with just 2 candidates, all voters will simply  
>> approve the
>> one they prefer to
>> the other, to give the Approval result:
>> 65: A
>> 35: B
>
> OK. This is a completely separate example of approval voting than your
> first example.  BTW, in any election:
>
> 1.  voters have to make a choice on how they vote and cannot vote more
> than one way in the same election using one ballot, and
>
> 2. the election has to be either conducted via one election method or
> another - I.e. approval voting is analogous to rating candidates 0
> (not approved) or 1 (approved), and so your above example shows ALL
> candidates are approved if one tries to switch that to approval from
> ratings.
>
> In this example A wins.
>
>> A wins. Now suppose that a third candidate (C) is introduced, and
>> including this extra
>> candidate the voters'? utilities are:
>>
>>
>> 40: A100, B98, C1
>> 25: C100, A98,?B1
>> 35: B100, C98, A1
>
> OK. In this example, removing the ratings to get approval voting
> example (a third example related to neither of the first two, ALL
> voters approve of A, B, and C and so A, B, and C are TIED again. It
> seems like a pretty unlikely scenario, but then I suppose it is
> possible.
>
>> Now all the voters have one candidate they like very much, another  
>> they
>> like nearly as much,
>> and one they like very much less.? The voters best zero-information
>> strategy is to all approve? 2
>> candidates, to give the Approval ballots:
>> 40: AB
>> 25: CA
>> 35: BC
>
> OK, in THIS (yet another separate example of approval voting which is
> not related to either of your prior examples in any way except by
> dropping particular candidates from prior examples), B wins.
>
> You are capable of understanding I hope that this example is entirely
> different from your prior examples and that none of your examples are
> of the same approval election?
>
> If you are illogically claiming that these three entirely separate
> examples are the same you must (I am guessing) be thinking in
> backwards fashion that you can devine voter ratings from approval
> ballots or that you can delusionally know how all voters would change
> ratings to approval votes and vice-versa.
>
> I.e. Certainly you must agree that:
>
> 1. voters must decide ONE way to cast their ONE ballot, and
>
> 2. it is not humanly possible to devine what ratings voters would give
> to each candidate from looking at their approval voting ballots
> because IF you are talking about APPROVAL voting, then there ARE NO
> RATINGS, and you might agree that no one has superhuman powers to know
> by looking at approval ballots, the ratings voters would give.
>
> Chris, If you want to provide an example that makes a lick of sense
> and does not assume that you can magically read all voters' minds, and
> is logical and valid for EITHER approval or range voting which
> exhibits the spoiler effect, then you must find an example that is
> RANGE voting alone or an example which is APPROVAL voting that
> exhibits the spoiler effect; or alternatively use only 0's and 1's to
> signify your approval voting ratings.
>
> Approval voting is analogous to giving a rating of 1 or 0, not the
> example you gave.
>
> So Chris, go back to the drawing board and eventually I believe that
> you will discover that you can NOT come up with a valid example of
> either approval or range voting that is susceptible to the spoiler
> effect.
>
> I.e. If you want to give an example where approval voting fails, use 1
> or 0 for your approval/disapproval for candidates. Otherwise come up
> with a range voting example, but your twisting all logic like you have
> done in order to come up with a fake example is very annoying because
> it is so stupid, and I am simply *not* going to respond to any more
> illogical silliness on your part Chris; nor am I going to continue to
> waste my time copying and pasting sentences from this list or from my
> paper which you have not bothered to read.
>
> Take the time to due your own research and reading and try again to
> come up with a *valid* example and take the time to READ what Abd ul
> and I have written, or stop wasting our time.
>
> Kathy
> ----
> Election-Methods mailing list - see http://electorama.com/em for  
> list info
>
> ----
> Election-Methods mailing list - see http://electorama.com/em for  
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