[EM] 3 or more choices - Condorcet

2012-11-08 Thread Chris Benham
Robert Bristow-Johnson wrote (1 Oct 2012):

my spin is similar.  Ranked Pairs simply says that some elections (or 
runoffs) speak more loudly than others.  those with higher margins are 
more definitive in expressing the will of the electorate than elections 
with small margins.  of course, a margin of zero is a tie and this says 
*nothing* regarding the will of the electorate, since it can go either way.

the reason i like margins over winning votes is that the margin, in vote 
count, is the product of the margin as a percent (that would be a 
measure of the decisiveness of the electorate) times the total number of 
votes (which is a measure of how important the election is).  so the 
margin in votes is the product of salience of the race times how 
decisive the decision is.

Say there are 3 candidates and the voters have the option to fully rank them,
but instead they all just choose to vote FPP-style thus:

 
49: A
48: B
03: C
 
Of course the only possible winner is A. Now say the election is held again 
(with
the same voters and candidates), and the B voters change to BC giving:


49: A
48: BC
03: C


Now to my mind this change adds strength to no candidate other than C, so the 
winner 
should either stay the same or change to C. Does anyone disagree?
 
So how do you (Robert or whoever the cap fits) justify to the A voters (and any 
fair-minded 
person not infatuated with the Margins pairwise algorithm) that the new Margins 
winner is B??
 
The pairwise comparisons: BC 48-3,  CA 51-49,  AB 49-48.

Ranked Pairs(Margins) gives the order BCA. 

I am happy with either A or C winning, but a win for C might look odd to people 
accustomed
to FPP and/or IRV.

 
*If* we insist on a Condorcet method that  uses only information contained in 
the pairwise
matrix (and so ignoring all positional or approval information) then *maybe* 
Losing Votes
is the best way to weigh the pairwise results. (So the strongest pairwise 
results are those where
the loser has the fewest votes and, put the other way, the weakest results are 
those where the
loser gets the most votes).

 
In the example Losing Votes elects A. Winning Votes elects C which I'm fine 
with, but I don't
like Winning Votes for other reasons.

Chris Benham
Election-Methods mailing list - see http://electorama.com/em for list info


Re: [EM] 3 or more choices - Condorcet

2012-11-08 Thread Ted Stern
Hi Chris,

You discuss Winning Votes vs. Margins below.

What do you think about using the Cardinal-Weighted Pairwise array in
conjunction with the traditional Condorcet array?

In other words, either WV or Margins is used to decide whether there
is a defeat, but the CWP array is used to determine the defeat
strength, in either Ranked Pairs or Schulze.

To recap for those not familiar with the technique (due to James
Green-Armytage in 2004), a ratings ballot is used: give a score of a_i
to candidate i.  Ranks are inferred: candidate i receives one
Condorcet vote over candidate j if a_i  a_j.

Whenever that Condorcet vote is recorded into the standard A_ij array,
you also tally the difference (a_i - a_j) into the corresponding
CWP_ij location.

Ted

On 08 Nov 2012 08:55:24 -0800, Chris Benham wrote:

 Robert Bristow-Johnson wrote (1 Oct 2012):

 my spin is similar.  Ranked Pairs simply says that some elections (or
 runoffs) speak more loudly than others.  those with higher margins are
 more definitive in expressing the will of the electorate than elections
 with small margins.  of course, a margin of zero is a tie and this says
 *nothing* regarding the will of the electorate, since it can go either way.

 the reason i like margins over winning votes is that the margin, in vote
 count, is the product of the margin as a percent (that would be a
 measure of the decisiveness of the electorate) times the total number of
 votes (which is a measure of how important the election is).  so the
 margin in votes is the product of salience of the race times how
 decisive the decision is.
 Say there are 3 candidates and the voters have the option to fully rank them,
 but instead they all just choose to vote FPP-style thus:

 49: A
 48: B
 03: C
  
 Of course the only possible winner is A. Now say the election is held again
 (with
 the same voters and candidates), and the B voters change to BC giving:

 49: A
 48: BC
 03: C

 Now to my mind this change adds strength to no candidate other than C, so the
 winner
 should either stay the same or change to C. Does anyone disagree?
  
 So how do you (Robert or whoever the cap fits) justify to the A voters (and 
 any
 fair-minded
 person not infatuated with the Margins pairwise algorithm) that the new 
 Margins
 winner is B??
  
 The pairwise comparisons: BC 48-3,  CA 51-49,  AB 49-48.
 Ranked Pairs(Margins) gives the order BCA. 

 I am happy with either A or C winning, but a win for C might look odd to 
 people
 accustomed
 to FPP and/or IRV.
  
 *If* we insist on a Condorcet method that  uses only information contained in
 the pairwise
 matrix (and so ignoring all positional or approval information) then *maybe*
 Losing Votes
 is the best way to weigh the pairwise results. (So the strongest pairwise
 results are those where
 the loser has the fewest votes and, put the other way, the weakest results are
 those where the
 loser gets the most votes).
  
 In the example Losing Votes elects A. Winning Votes elects C which I'm fine
 with, but I don't
 like Winning Votes for other reasons.

 Chris Benham


 
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Re: [EM] 3 or more choices - Condorcet

2012-11-08 Thread robert bristow-johnson

On 11/8/12 11:55 AM, Chris Benham wrote:

Robert Bristow-Johnson wrote (1 Oct 2012):

my spin is similar.  Ranked Pairs simply says that some elections (or
runoffs) speak more loudly than others.  those with higher margins are
more definitive in expressing the will of the electorate than elections
with small margins.  of course, a margin of zero is a tie and this says
*nothing* regarding the will of the electorate, since it can go either 
way.


the reason i like margins over winning votes is that the margin, in vote
count, is the product of the margin as a percent (that would be a
measure of the decisiveness of the electorate) times the total number of
votes (which is a measure of how important the election is).  so the
margin in votes is the product of salience of the race times how
decisive the decision is.
Say there are 3 candidates and the voters have the option to fully 
rank them,

but instead they all just choose to vote FPP-style thus:

49: A
48: B
03: C
Of course the only possible winner is A. Now say the election is held 
again (with

the same voters and candidates), and the B voters change to BC giving:

49: A
48: BC
03: C

Now to my mind this change adds strength to no candidate other 
than C, so the winner

should either stay the same or change to C. Does anyone disagree?
So how do you (Robert or whoever the cap fits) justify to the A voters 
(and any fair-minded
person not infatuated with the Margins pairwise algorithm) that the 
new Margins winner is B??

The pairwise comparisons: BC 48-3,  CA 51-49,  AB 49-48.
Ranked Pairs(Margins) gives the order BCA.

I am happy with either A or C winning, but a win for C might look odd 
to people accustomed

to FPP and/or IRV.
*If* we insist on a Condorcet method that  uses only information 
contained in the pairwise
matrix (and so ignoring all positional or approval information) then 
*maybe* Losing Votes
is the best way to weigh the pairwise results. (So the strongest 
pairwise results are those where
the loser has the fewest votes and, put the other way, the weakest 
results are those where the

loser gets the most votes).
In the example Losing Votes elects A. Winning Votes elects C which I'm 
fine with, but I don't

like Winning Votes for other reasons.




well, i'm not the guy with upper-case letters.  i didn't comment on this 
response to what i said, but looking it over right now, whether people 
vote on a Ranked-Choice ballot as if it were FPP or not, any candidates 
*not* ranked are tied for last place on that ballot.  so


49: A
48: B
03: C

is really
49: AB  AC
48: BA  BC
03: CA  CB


the difference with this:

49: A
48: BC
03: C

is that C gets a helluva lot more support from B voters than the other 
scenario.


49: AB  AC
48: BCA
03: CA  CB

it's the same old complaint that Rob Ritchie (FairVote) and others make 
against Condorcet (justifying putting all their support behind IRV): 
that (from their POV) Condorcet can elect wishy-washy candidates with 
little primary support.  i (and Condorcet) would say that in the second 
case, C is the best candidate even if he/she got only 3 first-choice 
votes.  might be a nice centrist, no-drama candidate in a polarized 
environment.  in Burlington VT 2009, the 3rd-place finisher from the POV 
or FPP or IRV was the Condorcet winner and nearly everyone i talked with 
would have been much happier with this candidate than with whom actually 
won the IRV or with whom would have won FPP (who suffered a decisive 
defeat in a repeat run in March 2012).  but the margins weren't so wide 
as with this example, candidate C got a lot more than 3% primary support 
votes.


again, i will repeat that probably, technically, Schulze is superior to 
Ranked-Pairs.  but it doesn't matter with a Smith Set of 3 candidates or 
less.  Condorcet cycles will be rare.  cycles with more than 3 in the 
Smith set will be rare of the rare.  it's best to get Condorcet of 
*some* method enacted into law.  the most realistic path to 
accomplishing that is *not* to advocate a method that cannot be 
explained to citizen-legislators.  and i still think that margins is 
better than either winning votes (or the logical complement regarding 
the most losing votes).  margins encompasses *both* winning votes and 
losing votes (the latter with a negative sign, of course).


--

r b-j  r...@audioimagination.com

Imagination is more important than knowledge.




Election-Methods mailing list - see http://electorama.com/em for list info


Re: [EM] 3 or more choices - Condorcet

2012-11-08 Thread robert bristow-johnson


this is the 2nd resend.  it's been hours since i first posted this and 
it hasn't shown up on the list.


On 11/8/12 11:55 AM, Chris Benham wrote:

Robert Bristow-Johnson wrote (1 Oct 2012):

my spin is similar.  Ranked Pairs simply says that some elections (or
runoffs) speak more loudly than others.  those with higher margins are
more definitive in expressing the will of the electorate than elections
with small margins.  of course, a margin of zero is a tie and this says
*nothing* regarding the will of the electorate, since it can go either
way.

the reason i like margins over winning votes is that the margin, in vote
count, is the product of the margin as a percent (that would be a
measure of the decisiveness of the electorate) times the total number of
votes (which is a measure of how important the election is).  so the
margin in votes is the product of salience of the race times how
decisive the decision is.
Say there are 3 candidates and the voters have the option to fully
rank them,
but instead they all just choose to vote FPP-style thus:

49: A
48: B
03: C
Of course the only possible winner is A. Now say the election is held
again (with
the same voters and candidates), and the B voters change to BC giving:

49: A
48: BC
03: C

Now to my mind this change adds strength to no candidate other
than C, so the winner
should either stay the same or change to C. Does anyone disagree?
So how do you (Robert or whoever the cap fits) justify to the A voters
(and any fair-minded
person not infatuated with the Margins pairwise algorithm) that the
new Margins winner is B??
The pairwise comparisons: BC 48-3,  CA 51-49,  AB 49-48.
Ranked Pairs(Margins) gives the order BCA.

I am happy with either A or C winning, but a win for C might look odd
to people accustomed
to FPP and/or IRV.
*If* we insist on a Condorcet method that  uses only information
contained in the pairwise
matrix (and so ignoring all positional or approval information) then
*maybe* Losing Votes
is the best way to weigh the pairwise results. (So the strongest
pairwise results are those where
the loser has the fewest votes and, put the other way, the weakest
results are those where the
loser gets the most votes).
In the example Losing Votes elects A. Winning Votes elects C which I'm
fine with, but I don't
like Winning Votes for other reasons.




well, i'm not the guy with upper-case letters.  i didn't comment on this 
response to what i said, but looking it over right now, whether people 
vote on a Ranked-Choice ballot as if it were FPP or not, any candidates 
*not* ranked are tied for last place on that ballot.  so


49: A
48: B
03: C

is really
49: AB  AC
48: BA  BC
03: CA  CB


the difference with this:

49: A
48: BC
03: C

is that C gets a helluva lot more support from B voters than the other 
scenario.


49: AB  AC
48: BCA
03: CA  CB

it's the same old complaint that Rob Ritchie (FairVote) and others make 
against Condorcet (justifying putting all their support behind IRV): 
that (from their POV) Condorcet can elect wishy-washy candidates with 
little primary support.  i (and Condorcet) would say that in the second 
case, C is the best candidate even if he/she got only 3 first-choice 
votes.  might be a nice centrist, no-drama candidate in a polarized 
environment.  in Burlington VT 2009, the 3rd-place finisher from the POV 
or FPP or IRV was the Condorcet winner and nearly everyone i talked with 
would have been much happier with this candidate than with whom actually 
won the IRV or with whom would have won FPP (who suffered a decisive 
defeat in a repeat run in March 2012).  but the margins weren't so wide 
as with this example, candidate C got a lot more than 3% primary support 
votes.


again, i will repeat that probably, technically, Schulze is superior to 
Ranked-Pairs.  but it doesn't matter with a Smith Set of 3 candidates or 
less.  Condorcet cycles will be rare.  cycles with more than 3 in the 
Smith set will be rare of the rare.  it's best to get Condorcet of 
*some* method enacted into law.  the most realistic path to 
accomplishing that is *not* to advocate a method that cannot be 
explained to citizen-legislators.  and i still think that margins is 
better than either winning votes (or the logical complement regarding 
the most losing votes).  margins encompasses *both* winning votes and 
losing votes (the latter with a negative sign, of course).


--

r b-j  r...@audioimagination.com

Imagination is more important than knowledge.




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[EM] testing 1,2,3.... hellooooo?

2012-11-08 Thread robert bristow-johnson


none of my messages seem to be getting posted to the EM list, today.

--

r b-j  r...@audioimagination.com

Imagination is more important than knowledge.




Election-Methods mailing list - see http://electorama.com/em for list info