RT
Richard, the VoteFair guy
Thu, Mar 31, 2022 5:10 PM
On 3/30/2022 11:51 PM, Colin Champion wrote:
... is the candidate with the highest support count not the
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Borda count is a positional voting method:
https://en.wikipedia.org/wiki/Positional_voting
As a tie breaker, only the candidates who are tied are considered in
this count.
When the tie is between just two candidates, the Borda count would still
use the (positional) numbers assigned by the voters.
In contrast, I'm recommending a counting method that disregards which
position contains the mark being counted. So a two-candidate tie
becomes simple plurality counting.
To repeat, I'm suggesting breaking a tie by using pairwise support
counts. On one ballot the pairwise support count is the number of
candidates who are ranked lower than the candidate getting the support
count. Those counts are added across all the ballots to yield that
candidate's pairwise support count.
A big advantage is that it can be counted directly from the ballots,
without first creating a pairwise matrix. Although software would use
the pairwise matrix approach, voters and the legal description and the
tabulated results would not mention the pairwise matrix.
Richard Fobes
The VoteFair guy
On 3/30/2022 11:51 PM, Colin Champion wrote:
Richard – is the candidate with the highest support count not the
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Colin
On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
Here I'm suggesting a way to improve the recently (fall 2021) created
"Ranked Robin" method, which is described at Electowiki at this link:
https://electowiki.org/wiki/Ranked_Robin
The improvement is to replace the first-level tie breaker -- which
looks at margins calculated from the pairwise matrix -- with "pairwise
support counts" -- which are easily described without using any
numbers from the pairwise matrix.
Starting from the beginning ...
Currently the Ranked Robin method is described this way:
"Elect the candidate who pairwise beats the greatest number of
candidates."
That's the method described by Ramon Llull (in 1299).
According to Electowiki that's been improved to become the Copeland
method, which elects "the candidate with the most (pairwise victories
minus pairwise defeats)."
According to Wikipedia the Copeland method doesn't do the subtraction
and instead adds "half the number of candidates with whom he or she
has a preference tie."
All of these Copeland method variations produce lots of ties.
So of course the Ranked Robin method needs tie breakers. Here's the
first-level tie breaker as it's currently specified:
"For each finalist, subtract the number of votes preferring each other
finalist from the number of votes preferring them over each other
finalist. The finalist with the greatest total difference is elected."
A big disadvantage of this Ranked Robin tie breaker is that it uses
numbers from the pairwise matrix. Yet one of the stated goals of the
Ranked Robin method is to avoid confusing voters with the pairwise
matrix.
Therefore I suggest replacing this tie-breaker method with the use of
"pairwise support counts." These counts are part of the "Instant
Pairwise Elimination" (IPE) method, which is described at Electowiki
at this link:
https://electowiki.org/wiki/Instant_Pairwise_Elimination
It says:
"If an elimination round has no pairwise-losing candidate, then the
method eliminates the candidate with the largest pairwise opposition
count, which is determined by counting on each ballot the number of
not-yet-eliminated candidates who are ranked above that candidate, and
adding those numbers across all the ballots. If there is a tie for the
largest pairwise opposition count, the method eliminates the candidate
with the smallest pairwise support count, which similarly counts
support rather than opposition. ..."
Of course the second-level tie-breaker would be to use pairwise
opposition counts. (The pairwise support counts and pairwise
opposition counts are not always symmetrical.)
Notice that the numbers in the pairwise matrix do not need to be
mentioned.
Yes, the software will calculate the pairwise support counts from the
numbers in the pairwise matrix. But that fact doesn't need to be
mentioned -- to the voters, or in the legal description.
The resulting improved Ranked Robin method can be described as follows:
"The [improved] Ranked Robin method elects the candidate who has the
most number of one-on-one wins against every other candidate plus half
the number of one-on-one ties. [*] If more than one candidate has the
same largest number, the method elects from those tied candidates the
candidate with the highest pairwise support count. The pairwise
support count for each of the tied candidates is the sum, across all
the ballots, of the number of tied [**] candidates who are ranked
lower than the candidate whose pairwise support count is being counted."
[*] The wording can be adjusted depending on which Copeland variation
is desired. Adding the words "minus the number of one-on-one losses"
would specify the other variation.
[**] Importantly, the ballot marks for the non-tied candidates must be
ignored when resolving the tie.
When the election results are displayed, they might look something
like this, where the names are from the Ranked Robin article, and the
numbers don't apply to any particular case:
Matchup win and loss counts:
Ava: 4 wins (against ...) and 2 losses (to ...)
Bianca: 4 wins (against ...) and 2 losses (to ...)
Cedric: 3 wins (against ...) and 3 losses (to ...)
Deegan: 3 wins (against ...) and 3 losses (to ...)
Eli: 2 wins (against ...) and 4 losses (to ...)
Fabio: 0 wins and 6 losses
The result is a tie between Ava and Bianca because they each have
4 wins, and that's more than any other candidate. Considering just
these tied candidates, their pairwise support counts are:
Ava: 213
Bianca: 123
So Ava wins!
Notice there's no need to show a pairwise matrix!
To prevent a potential source of confusion, the Wikipedia article
about the Borda count begins with the words "The Borda count is a
family of positional voting rules which gives each candidate, for each
ballot, a number of points corresponding to the number of candidates
ranked lower." The last portion of this sentence describes pairwise
support counts, but it has nothing to do with the Borda count. The
Wikipedia article for "positional voting" correctly says: "Positional
voting is a ranked voting electoral system in which the options or
candidates receive points based on their rank position on each ballot
and the one with the most points overall wins." The remainder of
Wikipedia's Borda count article correctly specifies positional voting
in the descriptions and examples. The Borda count article at
Electowiki does not include this first-sentence mistake. I'm going to
let someone else figure out how the first sentence in Wikipedia should
be worded. (I'd rather fight other battles.)
I'm calling attention to this difference between pairwise support
counts and the Borda count because this issue has previously caused
confusion in this forum.
Getting back to the Ranked Robin method, this improved version is not
likely to significantly increase the failure rates of the most
important failure criteria, and it's likely to reduce some failure rates.
Currently the Ranked Robin article claims that the method passes some
fairness criteria that it actually doesn't pass. When the Ranked
Robin article is improved to include a concise description of the
method (which should be near the beginning), some experts here can
identify which of the listed "pass" criteria need to be moved to the
listed "fail" criteria.
Interestingly, the Ranked Robin method and its name were created by
people who have previously promoted only STAR voting. I'm pleased
that they are finally recognizing that STAR ballots are not going to
replace ranked choice ballots throughout the US. And that they
recognize the need to promote a method that takes advantage of the
Forward Party's recommendation of "ranked choice voting."
Looking at the broader perspective ...
The current version of Ranked Robin already has these advantages:
-
Uses pairwise vote counting, which looks deeper into the ballot
preferences compared to instant-runoff voting.
-
Is precinct summable.
-
Allows voters to mark more than one candidate at the same ranking
level.
I suggest making it even easier to understand by using pairwise
support counts. This improvement will eliminate the need to educate
voters about the pairwise matrix. And I believe this change will
still provide a similar level of fairness.
Certainly, in multiple ways, it's much better than instant-runoff voting.
Richard Fobes
The VoteFair guy
Election-Methods mailing list - see https://electorama.com/em for list
info
On 3/30/2022 11:51 PM, Colin Champion wrote:
> ... is the candidate with the highest support count not the
> candidate with the highest Borda score? Have you not reinvented
> Dasgupta-Maskin?
Borda count is a positional voting method:
https://en.wikipedia.org/wiki/Positional_voting
As a tie breaker, only the candidates who are tied are considered in
this count.
When the tie is between just two candidates, the Borda count would still
use the (positional) numbers assigned by the voters.
In contrast, I'm recommending a counting method that disregards which
position contains the mark being counted. So a two-candidate tie
becomes simple plurality counting.
To repeat, I'm suggesting breaking a tie by using pairwise support
counts. On one ballot the pairwise support count is the number of
candidates who are ranked lower than the candidate getting the support
count. Those counts are added across all the ballots to yield that
candidate's pairwise support count.
A big advantage is that it can be counted directly from the ballots,
without first creating a pairwise matrix. Although software would use
the pairwise matrix approach, voters and the legal description and the
tabulated results would not mention the pairwise matrix.
Richard Fobes
The VoteFair guy
On 3/30/2022 11:51 PM, Colin Champion wrote:
> Richard – is the candidate with the highest support count not the
> candidate with the highest Borda score? Have you not reinvented
> Dasgupta-Maskin?
> Colin
>
>
> On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
>> Here I'm suggesting a way to improve the recently (fall 2021) created
>> "Ranked Robin" method, which is described at Electowiki at this link:
>>
>> https://electowiki.org/wiki/Ranked_Robin
>>
>> The improvement is to replace the first-level tie breaker -- which
>> looks at margins calculated from the pairwise matrix -- with "pairwise
>> support counts" -- which are easily described without using any
>> numbers from the pairwise matrix.
>>
>> Starting from the beginning ...
>>
>> Currently the Ranked Robin method is described this way:
>>
>> "Elect the candidate who pairwise beats the greatest number of
>> candidates."
>>
>> That's the method described by Ramon Llull (in 1299).
>>
>> According to Electowiki that's been improved to become the Copeland
>> method, which elects "the candidate with the most (pairwise victories
>> minus pairwise defeats)."
>>
>> According to Wikipedia the Copeland method doesn't do the subtraction
>> and instead adds "half the number of candidates with whom he or she
>> has a preference tie."
>>
>> All of these Copeland method variations produce lots of ties.
>>
>> So of course the Ranked Robin method needs tie breakers. Here's the
>> first-level tie breaker as it's currently specified:
>>
>> "For each finalist, subtract the number of votes preferring each other
>> finalist from the number of votes preferring them over each other
>> finalist. The finalist with the greatest total difference is elected."
>>
>> A big disadvantage of this Ranked Robin tie breaker is that it uses
>> numbers from the pairwise matrix. Yet one of the stated goals of the
>> Ranked Robin method is to avoid confusing voters with the pairwise
>> matrix.
>>
>> Therefore I suggest replacing this tie-breaker method with the use of
>> "pairwise support counts." These counts are part of the "Instant
>> Pairwise Elimination" (IPE) method, which is described at Electowiki
>> at this link:
>>
>> https://electowiki.org/wiki/Instant_Pairwise_Elimination
>>
>> It says:
>>
>> "If an elimination round has no pairwise-losing candidate, then the
>> method eliminates the candidate with the largest pairwise opposition
>> count, which is determined by counting on each ballot the number of
>> not-yet-eliminated candidates who are ranked above that candidate, and
>> adding those numbers across all the ballots. If there is a tie for the
>> largest pairwise opposition count, the method eliminates the candidate
>> with the smallest pairwise support count, which similarly counts
>> support rather than opposition. ..."
>>
>> Of course the second-level tie-breaker would be to use pairwise
>> opposition counts. (The pairwise support counts and pairwise
>> opposition counts are not always symmetrical.)
>>
>> Notice that the numbers in the pairwise matrix do not need to be
>> mentioned.
>>
>> Yes, the software will calculate the pairwise support counts from the
>> numbers in the pairwise matrix. But that fact doesn't need to be
>> mentioned -- to the voters, or in the legal description.
>>
>> The resulting improved Ranked Robin method can be described as follows:
>>
>> "The [improved] Ranked Robin method elects the candidate who has the
>> most number of one-on-one wins against every other candidate plus half
>> the number of one-on-one ties. [*] If more than one candidate has the
>> same largest number, the method elects from those tied candidates the
>> candidate with the highest pairwise support count. The pairwise
>> support count for each of the tied candidates is the sum, across all
>> the ballots, of the number of tied [**] candidates who are ranked
>> lower than the candidate whose pairwise support count is being counted."
>>
>> [*] The wording can be adjusted depending on which Copeland variation
>> is desired. Adding the words "minus the number of one-on-one losses"
>> would specify the other variation.
>>
>> [**] Importantly, the ballot marks for the non-tied candidates must be
>> ignored when resolving the tie.
>>
>> When the election results are displayed, they might look something
>> like this, where the names are from the Ranked Robin article, and the
>> numbers don't apply to any particular case:
>>
>>
>> Matchup win and loss counts:
>>
>> Ava: 4 wins (against ...) and 2 losses (to ...)
>>
>> Bianca: 4 wins (against ...) and 2 losses (to ...)
>>
>> Cedric: 3 wins (against ...) and 3 losses (to ...)
>>
>> Deegan: 3 wins (against ...) and 3 losses (to ...)
>>
>> Eli: 2 wins (against ...) and 4 losses (to ...)
>>
>> Fabio: 0 wins and 6 losses
>>
>>
>> The result is a tie between Ava and Bianca because they each have
>> 4 wins, and that's more than any other candidate. Considering just
>> these tied candidates, their pairwise support counts are:
>>
>> Ava: 213
>>
>> Bianca: 123
>>
>> So Ava wins!
>>
>>
>> Notice there's no need to show a pairwise matrix!
>>
>> To prevent a potential source of confusion, the Wikipedia article
>> about the Borda count begins with the words "The Borda count is a
>> family of positional voting rules which gives each candidate, for each
>> ballot, a number of points corresponding to the number of candidates
>> ranked lower." The last portion of this sentence describes pairwise
>> support counts, but it has nothing to do with the Borda count. The
>> Wikipedia article for "positional voting" correctly says: "Positional
>> voting is a ranked voting electoral system in which the options or
>> candidates receive points based on their rank position on each ballot
>> and the one with the most points overall wins." The remainder of
>> Wikipedia's Borda count article correctly specifies positional voting
>> in the descriptions and examples. The Borda count article at
>> Electowiki does not include this first-sentence mistake. I'm going to
>> let someone else figure out how the first sentence in Wikipedia should
>> be worded. (I'd rather fight other battles.)
>>
>> I'm calling attention to this difference between pairwise support
>> counts and the Borda count because this issue has previously caused
>> confusion in this forum.
>>
>> Getting back to the Ranked Robin method, this improved version is not
>> likely to significantly increase the failure rates of the most
>> important failure criteria, and it's likely to reduce some failure rates.
>>
>> Currently the Ranked Robin article claims that the method passes some
>> fairness criteria that it actually doesn't pass. When the Ranked
>> Robin article is improved to include a concise description of the
>> method (which should be near the beginning), some experts here can
>> identify which of the listed "pass" criteria need to be moved to the
>> listed "fail" criteria.
>>
>> Interestingly, the Ranked Robin method and its name were created by
>> people who have previously promoted only STAR voting. I'm pleased
>> that they are finally recognizing that STAR ballots are not going to
>> replace ranked choice ballots throughout the US. And that they
>> recognize the need to promote a method that takes advantage of the
>> Forward Party's recommendation of "ranked choice voting."
>>
>> Looking at the broader perspective ...
>>
>> The current version of Ranked Robin already has these advantages:
>>
>> * Uses pairwise vote counting, which looks deeper into the ballot
>> preferences compared to instant-runoff voting.
>>
>> * Is precinct summable.
>>
>> * Allows voters to mark more than one candidate at the same ranking
>> level.
>>
>> I suggest making it even easier to understand by using pairwise
>> support counts. This improvement will eliminate the need to educate
>> voters about the pairwise matrix. And I believe this change will
>> still provide a similar level of fairness.
>>
>> Certainly, in multiple ways, it's much better than instant-runoff voting.
>>
>> Richard Fobes
>> The VoteFair guy
>> ----
>> Election-Methods mailing list - see https://electorama.com/em for list
>> info
>
CC
Colin Champion
Thu, Mar 31, 2022 6:55 PM
Richard – there are two ways of using a Borda tiebreak, sometimes
written "Llull//Borda" and "Llull,Borda". It sounds like you understood
me to be attributing "Llull,Borda" to you while you were actually
advocating "Llull//Borda". (I have no idea which of these was Dasgupta
and Maskin’s preference – I don’t think they were clear.) Certainly
Llull//Borda reduces to a plurality choice between two tied candidates.
Other tiebreaks (eg. minimax) can be used in the same two ways,
which is why a fairly general notation exists. I can't say I like it as
a notation, since it's far from self-explanatory.
Colin
On 31/03/2022 18:10, Richard, the VoteFair guy wrote:
On 3/30/2022 11:51 PM, Colin Champion wrote:
... is the candidate with the highest support count not the
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Borda count is a positional voting method:
https://en.wikipedia.org/wiki/Positional_voting
As a tie breaker, only the candidates who are tied are considered in
this count.
When the tie is between just two candidates, the Borda count would
still use the (positional) numbers assigned by the voters.
In contrast, I'm recommending a counting method that disregards which
position contains the mark being counted. So a two-candidate tie
becomes simple plurality counting.
To repeat, I'm suggesting breaking a tie by using pairwise support
counts. On one ballot the pairwise support count is the number of
candidates who are ranked lower than the candidate getting the support
count. Those counts are added across all the ballots to yield that
candidate's pairwise support count.
A big advantage is that it can be counted directly from the ballots,
without first creating a pairwise matrix. Although software would use
the pairwise matrix approach, voters and the legal description and the
tabulated results would not mention the pairwise matrix.
Richard Fobes
The VoteFair guy
On 3/30/2022 11:51 PM, Colin Champion wrote:
Richard – is the candidate with the highest support count not the
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Colin
On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
Here I'm suggesting a way to improve the recently (fall 2021) created
"Ranked Robin" method, which is described at Electowiki at this link:
https://electowiki.org/wiki/Ranked_Robin
The improvement is to replace the first-level tie breaker -- which
looks at margins calculated from the pairwise matrix -- with "pairwise
support counts" -- which are easily described without using any
numbers from the pairwise matrix.
Starting from the beginning ...
Currently the Ranked Robin method is described this way:
"Elect the candidate who pairwise beats the greatest number of
candidates."
That's the method described by Ramon Llull (in 1299).
According to Electowiki that's been improved to become the Copeland
method, which elects "the candidate with the most (pairwise victories
minus pairwise defeats)."
According to Wikipedia the Copeland method doesn't do the subtraction
and instead adds "half the number of candidates with whom he or she
has a preference tie."
All of these Copeland method variations produce lots of ties.
So of course the Ranked Robin method needs tie breakers. Here's the
first-level tie breaker as it's currently specified:
"For each finalist, subtract the number of votes preferring each other
finalist from the number of votes preferring them over each other
finalist. The finalist with the greatest total difference is elected."
A big disadvantage of this Ranked Robin tie breaker is that it uses
numbers from the pairwise matrix. Yet one of the stated goals of the
Ranked Robin method is to avoid confusing voters with the pairwise
matrix.
Therefore I suggest replacing this tie-breaker method with the use of
"pairwise support counts." These counts are part of the "Instant
Pairwise Elimination" (IPE) method, which is described at Electowiki
at this link:
https://electowiki.org/wiki/Instant_Pairwise_Elimination
It says:
"If an elimination round has no pairwise-losing candidate, then the
method eliminates the candidate with the largest pairwise opposition
count, which is determined by counting on each ballot the number of
not-yet-eliminated candidates who are ranked above that candidate, and
adding those numbers across all the ballots. If there is a tie for the
largest pairwise opposition count, the method eliminates the candidate
with the smallest pairwise support count, which similarly counts
support rather than opposition. ..."
Of course the second-level tie-breaker would be to use pairwise
opposition counts. (The pairwise support counts and pairwise
opposition counts are not always symmetrical.)
Notice that the numbers in the pairwise matrix do not need to be
mentioned.
Yes, the software will calculate the pairwise support counts from the
numbers in the pairwise matrix. But that fact doesn't need to be
mentioned -- to the voters, or in the legal description.
The resulting improved Ranked Robin method can be described as follows:
"The [improved] Ranked Robin method elects the candidate who has the
most number of one-on-one wins against every other candidate plus half
the number of one-on-one ties. [*] If more than one candidate has the
same largest number, the method elects from those tied candidates the
candidate with the highest pairwise support count. The pairwise
support count for each of the tied candidates is the sum, across all
the ballots, of the number of tied [**] candidates who are ranked
lower than the candidate whose pairwise support count is being
counted."
[*] The wording can be adjusted depending on which Copeland variation
is desired. Adding the words "minus the number of one-on-one losses"
would specify the other variation.
[**] Importantly, the ballot marks for the non-tied candidates must be
ignored when resolving the tie.
When the election results are displayed, they might look something
like this, where the names are from the Ranked Robin article, and the
numbers don't apply to any particular case:
Matchup win and loss counts:
Ava: 4 wins (against ...) and 2 losses (to ...)
Bianca: 4 wins (against ...) and 2 losses (to ...)
Cedric: 3 wins (against ...) and 3 losses (to ...)
Deegan: 3 wins (against ...) and 3 losses (to ...)
Eli: 2 wins (against ...) and 4 losses (to ...)
Fabio: 0 wins and 6 losses
The result is a tie between Ava and Bianca because they each have
4 wins, and that's more than any other candidate. Considering just
these tied candidates, their pairwise support counts are:
Ava: 213
Bianca: 123
So Ava wins!
Notice there's no need to show a pairwise matrix!
To prevent a potential source of confusion, the Wikipedia article
about the Borda count begins with the words "The Borda count is a
family of positional voting rules which gives each candidate, for each
ballot, a number of points corresponding to the number of candidates
ranked lower." The last portion of this sentence describes pairwise
support counts, but it has nothing to do with the Borda count. The
Wikipedia article for "positional voting" correctly says: "Positional
voting is a ranked voting electoral system in which the options or
candidates receive points based on their rank position on each ballot
and the one with the most points overall wins." The remainder of
Wikipedia's Borda count article correctly specifies positional voting
in the descriptions and examples. The Borda count article at
Electowiki does not include this first-sentence mistake. I'm going to
let someone else figure out how the first sentence in Wikipedia should
be worded. (I'd rather fight other battles.)
I'm calling attention to this difference between pairwise support
counts and the Borda count because this issue has previously caused
confusion in this forum.
Getting back to the Ranked Robin method, this improved version is not
likely to significantly increase the failure rates of the most
important failure criteria, and it's likely to reduce some failure
rates.
Currently the Ranked Robin article claims that the method passes some
fairness criteria that it actually doesn't pass. When the Ranked
Robin article is improved to include a concise description of the
method (which should be near the beginning), some experts here can
identify which of the listed "pass" criteria need to be moved to the
listed "fail" criteria.
Interestingly, the Ranked Robin method and its name were created by
people who have previously promoted only STAR voting. I'm pleased
that they are finally recognizing that STAR ballots are not going to
replace ranked choice ballots throughout the US. And that they
recognize the need to promote a method that takes advantage of the
Forward Party's recommendation of "ranked choice voting."
Looking at the broader perspective ...
The current version of Ranked Robin already has these advantages:
-
Uses pairwise vote counting, which looks deeper into the ballot
preferences compared to instant-runoff voting.
-
Is precinct summable.
-
Allows voters to mark more than one candidate at the same ranking
level.
I suggest making it even easier to understand by using pairwise
support counts. This improvement will eliminate the need to educate
voters about the pairwise matrix. And I believe this change will
still provide a similar level of fairness.
Certainly, in multiple ways, it's much better than instant-runoff
voting.
Richard Fobes
The VoteFair guy
Election-Methods mailing list - see https://electorama.com/em for list
info
Richard – there are two ways of using a Borda tiebreak, sometimes
written "Llull//Borda" and "Llull,Borda". It sounds like you understood
me to be attributing "Llull,Borda" to you while you were actually
advocating "Llull//Borda". (I have no idea which of these was Dasgupta
and Maskin’s preference – I don’t think they were clear.) Certainly
Llull//Borda reduces to a plurality choice between two tied candidates.
Other tiebreaks (eg. minimax) can be used in the same two ways,
which is why a fairly general notation exists. I can't say I like it as
a notation, since it's far from self-explanatory.
Colin
On 31/03/2022 18:10, Richard, the VoteFair guy wrote:
> On 3/30/2022 11:51 PM, Colin Champion wrote:
> > ... is the candidate with the highest support count not the
> > candidate with the highest Borda score? Have you not reinvented
> > Dasgupta-Maskin?
>
> Borda count is a positional voting method:
>
> https://en.wikipedia.org/wiki/Positional_voting
>
> As a tie breaker, only the candidates who are tied are considered in
> this count.
>
> When the tie is between just two candidates, the Borda count would
> still use the (positional) numbers assigned by the voters.
>
> In contrast, I'm recommending a counting method that disregards which
> position contains the mark being counted. So a two-candidate tie
> becomes simple plurality counting.
>
> To repeat, I'm suggesting breaking a tie by using pairwise support
> counts. On one ballot the pairwise support count is the number of
> candidates who are ranked lower than the candidate getting the support
> count. Those counts are added across all the ballots to yield that
> candidate's pairwise support count.
>
> A big advantage is that it can be counted directly from the ballots,
> without first creating a pairwise matrix. Although software would use
> the pairwise matrix approach, voters and the legal description and the
> tabulated results would not mention the pairwise matrix.
>
> Richard Fobes
> The VoteFair guy
>
>
> On 3/30/2022 11:51 PM, Colin Champion wrote:
>> Richard – is the candidate with the highest support count not the
>> candidate with the highest Borda score? Have you not reinvented
>> Dasgupta-Maskin?
>> Colin
>>
>>
>> On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
>>> Here I'm suggesting a way to improve the recently (fall 2021) created
>>> "Ranked Robin" method, which is described at Electowiki at this link:
>>>
>>> https://electowiki.org/wiki/Ranked_Robin
>>>
>>> The improvement is to replace the first-level tie breaker -- which
>>> looks at margins calculated from the pairwise matrix -- with "pairwise
>>> support counts" -- which are easily described without using any
>>> numbers from the pairwise matrix.
>>>
>>> Starting from the beginning ...
>>>
>>> Currently the Ranked Robin method is described this way:
>>>
>>> "Elect the candidate who pairwise beats the greatest number of
>>> candidates."
>>>
>>> That's the method described by Ramon Llull (in 1299).
>>>
>>> According to Electowiki that's been improved to become the Copeland
>>> method, which elects "the candidate with the most (pairwise victories
>>> minus pairwise defeats)."
>>>
>>> According to Wikipedia the Copeland method doesn't do the subtraction
>>> and instead adds "half the number of candidates with whom he or she
>>> has a preference tie."
>>>
>>> All of these Copeland method variations produce lots of ties.
>>>
>>> So of course the Ranked Robin method needs tie breakers. Here's the
>>> first-level tie breaker as it's currently specified:
>>>
>>> "For each finalist, subtract the number of votes preferring each other
>>> finalist from the number of votes preferring them over each other
>>> finalist. The finalist with the greatest total difference is elected."
>>>
>>> A big disadvantage of this Ranked Robin tie breaker is that it uses
>>> numbers from the pairwise matrix. Yet one of the stated goals of the
>>> Ranked Robin method is to avoid confusing voters with the pairwise
>>> matrix.
>>>
>>> Therefore I suggest replacing this tie-breaker method with the use of
>>> "pairwise support counts." These counts are part of the "Instant
>>> Pairwise Elimination" (IPE) method, which is described at Electowiki
>>> at this link:
>>>
>>> https://electowiki.org/wiki/Instant_Pairwise_Elimination
>>>
>>> It says:
>>>
>>> "If an elimination round has no pairwise-losing candidate, then the
>>> method eliminates the candidate with the largest pairwise opposition
>>> count, which is determined by counting on each ballot the number of
>>> not-yet-eliminated candidates who are ranked above that candidate, and
>>> adding those numbers across all the ballots. If there is a tie for the
>>> largest pairwise opposition count, the method eliminates the candidate
>>> with the smallest pairwise support count, which similarly counts
>>> support rather than opposition. ..."
>>>
>>> Of course the second-level tie-breaker would be to use pairwise
>>> opposition counts. (The pairwise support counts and pairwise
>>> opposition counts are not always symmetrical.)
>>>
>>> Notice that the numbers in the pairwise matrix do not need to be
>>> mentioned.
>>>
>>> Yes, the software will calculate the pairwise support counts from the
>>> numbers in the pairwise matrix. But that fact doesn't need to be
>>> mentioned -- to the voters, or in the legal description.
>>>
>>> The resulting improved Ranked Robin method can be described as follows:
>>>
>>> "The [improved] Ranked Robin method elects the candidate who has the
>>> most number of one-on-one wins against every other candidate plus half
>>> the number of one-on-one ties. [*] If more than one candidate has the
>>> same largest number, the method elects from those tied candidates the
>>> candidate with the highest pairwise support count. The pairwise
>>> support count for each of the tied candidates is the sum, across all
>>> the ballots, of the number of tied [**] candidates who are ranked
>>> lower than the candidate whose pairwise support count is being
>>> counted."
>>>
>>> [*] The wording can be adjusted depending on which Copeland variation
>>> is desired. Adding the words "minus the number of one-on-one losses"
>>> would specify the other variation.
>>>
>>> [**] Importantly, the ballot marks for the non-tied candidates must be
>>> ignored when resolving the tie.
>>>
>>> When the election results are displayed, they might look something
>>> like this, where the names are from the Ranked Robin article, and the
>>> numbers don't apply to any particular case:
>>>
>>>
>>> Matchup win and loss counts:
>>>
>>> Ava: 4 wins (against ...) and 2 losses (to ...)
>>>
>>> Bianca: 4 wins (against ...) and 2 losses (to ...)
>>>
>>> Cedric: 3 wins (against ...) and 3 losses (to ...)
>>>
>>> Deegan: 3 wins (against ...) and 3 losses (to ...)
>>>
>>> Eli: 2 wins (against ...) and 4 losses (to ...)
>>>
>>> Fabio: 0 wins and 6 losses
>>>
>>>
>>> The result is a tie between Ava and Bianca because they each have
>>> 4 wins, and that's more than any other candidate. Considering just
>>> these tied candidates, their pairwise support counts are:
>>>
>>> Ava: 213
>>>
>>> Bianca: 123
>>>
>>> So Ava wins!
>>>
>>>
>>> Notice there's no need to show a pairwise matrix!
>>>
>>> To prevent a potential source of confusion, the Wikipedia article
>>> about the Borda count begins with the words "The Borda count is a
>>> family of positional voting rules which gives each candidate, for each
>>> ballot, a number of points corresponding to the number of candidates
>>> ranked lower." The last portion of this sentence describes pairwise
>>> support counts, but it has nothing to do with the Borda count. The
>>> Wikipedia article for "positional voting" correctly says: "Positional
>>> voting is a ranked voting electoral system in which the options or
>>> candidates receive points based on their rank position on each ballot
>>> and the one with the most points overall wins." The remainder of
>>> Wikipedia's Borda count article correctly specifies positional voting
>>> in the descriptions and examples. The Borda count article at
>>> Electowiki does not include this first-sentence mistake. I'm going to
>>> let someone else figure out how the first sentence in Wikipedia should
>>> be worded. (I'd rather fight other battles.)
>>>
>>> I'm calling attention to this difference between pairwise support
>>> counts and the Borda count because this issue has previously caused
>>> confusion in this forum.
>>>
>>> Getting back to the Ranked Robin method, this improved version is not
>>> likely to significantly increase the failure rates of the most
>>> important failure criteria, and it's likely to reduce some failure
>>> rates.
>>>
>>> Currently the Ranked Robin article claims that the method passes some
>>> fairness criteria that it actually doesn't pass. When the Ranked
>>> Robin article is improved to include a concise description of the
>>> method (which should be near the beginning), some experts here can
>>> identify which of the listed "pass" criteria need to be moved to the
>>> listed "fail" criteria.
>>>
>>> Interestingly, the Ranked Robin method and its name were created by
>>> people who have previously promoted only STAR voting. I'm pleased
>>> that they are finally recognizing that STAR ballots are not going to
>>> replace ranked choice ballots throughout the US. And that they
>>> recognize the need to promote a method that takes advantage of the
>>> Forward Party's recommendation of "ranked choice voting."
>>>
>>> Looking at the broader perspective ...
>>>
>>> The current version of Ranked Robin already has these advantages:
>>>
>>> * Uses pairwise vote counting, which looks deeper into the ballot
>>> preferences compared to instant-runoff voting.
>>>
>>> * Is precinct summable.
>>>
>>> * Allows voters to mark more than one candidate at the same ranking
>>> level.
>>>
>>> I suggest making it even easier to understand by using pairwise
>>> support counts. This improvement will eliminate the need to educate
>>> voters about the pairwise matrix. And I believe this change will
>>> still provide a similar level of fairness.
>>>
>>> Certainly, in multiple ways, it's much better than instant-runoff
>>> voting.
>>>
>>> Richard Fobes
>>> The VoteFair guy
>>> ----
>>> Election-Methods mailing list - see https://electorama.com/em for list
>>> info
>>
FS
Forest Simmons
Sat, Apr 2, 2022 1:24 AM
Besides being prone to ties, Copeland also suffers from Clone Dependence,
which makes it inferior to IRV in that regard.
Here are two versions of decloned Copeland that are not prone to ties:
1.Elect the candidate that, on the greatest number of ballots, pairwise
defeats the candidate designated "worst."
That is the burial resistant version of decloned Copeland.
The other version, that may be more appealing to some people, is this:
- Elect the candidate that, on the fewest number of ballots, is pairwise
defeated by the candidate designated "best."
Both of these methods are monotonic, clone free, and "Round Robin
Efficient."
It is practically impossible for either method to yield a tied result in an
actual political election involving hundreds of ballots.
Because of that fact, the obligatory tie breaker does not need the special
scrutiny that is so important for ordinary clone dependent Copeland.
Random Favorite would be the simplest ... and perfectly adequate tie
breaker.
At the other end of the spectrum, method one could serve as the tie breaker
for method two, and vice-versa.
Between those possibilities there are many others that are also perfectly
adequate.
-Forest
El jue., 31 de mar. de 2022 12:04 p. m., Colin Champion <
colin.champion@routemaster.app> escribió:
Richard – there are two ways of using a Borda tiebreak, sometimes written
"Llull//Borda" and "Llull,Borda". It sounds like you understood me to be
attributing "Llull,Borda" to you while you were actually advocating
"Llull//Borda". (I have no idea which of these was Dasgupta and Maskin’s
preference – I don’t think they were clear.) Certainly Llull//Borda reduces
to a plurality choice between two tied candidates.
Other tiebreaks (eg. minimax) can be used in the same two ways, which
is why a fairly general notation exists. I can't say I like it as a
notation, since it's far from self-explanatory.
Colin
On 31/03/2022 18:10, Richard, the VoteFair guy wrote:
On 3/30/2022 11:51 PM, Colin Champion wrote:
... is the candidate with the highest support count not the
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Borda count is a positional voting method:
https://en.wikipedia.org/wiki/Positional_voting
As a tie breaker, only the candidates who are tied are considered in this
count.
When the tie is between just two candidates, the Borda count would still
use the (positional) numbers assigned by the voters.
In contrast, I'm recommending a counting method that disregards which
position contains the mark being counted. So a two-candidate tie becomes
simple plurality counting.
To repeat, I'm suggesting breaking a tie by using pairwise support
counts. On one ballot the pairwise support count is the number of
candidates who are ranked lower than the candidate getting the support
count. Those counts are added across all the ballots to yield that
candidate's pairwise support count.
A big advantage is that it can be counted directly from the ballots,
without first creating a pairwise matrix. Although software would use the
pairwise matrix approach, voters and the legal description and the
tabulated results would not mention the pairwise matrix.
Richard Fobes
The VoteFair guy
On 3/30/2022 11:51 PM, Colin Champion wrote:
Richard – is the candidate with the highest support count not the
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Colin
On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
Here I'm suggesting a way to improve the recently (fall 2021) created
"Ranked Robin" method, which is described at Electowiki at this link:
https://electowiki.org/wiki/Ranked_Robin
The improvement is to replace the first-level tie breaker -- which
looks at margins calculated from the pairwise matrix -- with "pairwise
support counts" -- which are easily described without using any
numbers from the pairwise matrix.
Starting from the beginning ...
Currently the Ranked Robin method is described this way:
"Elect the candidate who pairwise beats the greatest number of
candidates."
That's the method described by Ramon Llull (in 1299).
According to Electowiki that's been improved to become the Copeland
method, which elects "the candidate with the most (pairwise victories
minus pairwise defeats)."
According to Wikipedia the Copeland method doesn't do the subtraction
and instead adds "half the number of candidates with whom he or she
has a preference tie."
All of these Copeland method variations produce lots of ties.
So of course the Ranked Robin method needs tie breakers. Here's the
first-level tie breaker as it's currently specified:
"For each finalist, subtract the number of votes preferring each other
finalist from the number of votes preferring them over each other
finalist. The finalist with the greatest total difference is elected."
A big disadvantage of this Ranked Robin tie breaker is that it uses
numbers from the pairwise matrix. Yet one of the stated goals of the
Ranked Robin method is to avoid confusing voters with the pairwise
matrix.
Therefore I suggest replacing this tie-breaker method with the use of
"pairwise support counts." These counts are part of the "Instant
Pairwise Elimination" (IPE) method, which is described at Electowiki
at this link:
https://electowiki.org/wiki/Instant_Pairwise_Elimination
It says:
"If an elimination round has no pairwise-losing candidate, then the
method eliminates the candidate with the largest pairwise opposition
count, which is determined by counting on each ballot the number of
not-yet-eliminated candidates who are ranked above that candidate, and
adding those numbers across all the ballots. If there is a tie for the
largest pairwise opposition count, the method eliminates the candidate
with the smallest pairwise support count, which similarly counts
support rather than opposition. ..."
Of course the second-level tie-breaker would be to use pairwise
opposition counts. (The pairwise support counts and pairwise
opposition counts are not always symmetrical.)
Notice that the numbers in the pairwise matrix do not need to be
mentioned.
Yes, the software will calculate the pairwise support counts from the
numbers in the pairwise matrix. But that fact doesn't need to be
mentioned -- to the voters, or in the legal description.
The resulting improved Ranked Robin method can be described as follows:
"The [improved] Ranked Robin method elects the candidate who has the
most number of one-on-one wins against every other candidate plus half
the number of one-on-one ties. [*] If more than one candidate has the
same largest number, the method elects from those tied candidates the
candidate with the highest pairwise support count. The pairwise
support count for each of the tied candidates is the sum, across all
the ballots, of the number of tied [**] candidates who are ranked
lower than the candidate whose pairwise support count is being counted."
[*] The wording can be adjusted depending on which Copeland variation
is desired. Adding the words "minus the number of one-on-one losses"
would specify the other variation.
[**] Importantly, the ballot marks for the non-tied candidates must be
ignored when resolving the tie.
When the election results are displayed, they might look something
like this, where the names are from the Ranked Robin article, and the
numbers don't apply to any particular case:
Matchup win and loss counts:
Ava: 4 wins (against ...) and 2 losses (to ...)
Bianca: 4 wins (against ...) and 2 losses (to ...)
Cedric: 3 wins (against ...) and 3 losses (to ...)
Deegan: 3 wins (against ...) and 3 losses (to ...)
Eli: 2 wins (against ...) and 4 losses (to ...)
Fabio: 0 wins and 6 losses
The result is a tie between Ava and Bianca because they each have
4 wins, and that's more than any other candidate. Considering just
these tied candidates, their pairwise support counts are:
Ava: 213
Bianca: 123
So Ava wins!
Notice there's no need to show a pairwise matrix!
To prevent a potential source of confusion, the Wikipedia article
about the Borda count begins with the words "The Borda count is a
family of positional voting rules which gives each candidate, for each
ballot, a number of points corresponding to the number of candidates
ranked lower." The last portion of this sentence describes pairwise
support counts, but it has nothing to do with the Borda count. The
Wikipedia article for "positional voting" correctly says: "Positional
voting is a ranked voting electoral system in which the options or
candidates receive points based on their rank position on each ballot
and the one with the most points overall wins." The remainder of
Wikipedia's Borda count article correctly specifies positional voting
in the descriptions and examples. The Borda count article at
Electowiki does not include this first-sentence mistake. I'm going to
let someone else figure out how the first sentence in Wikipedia should
be worded. (I'd rather fight other battles.)
I'm calling attention to this difference between pairwise support
counts and the Borda count because this issue has previously caused
confusion in this forum.
Getting back to the Ranked Robin method, this improved version is not
likely to significantly increase the failure rates of the most
important failure criteria, and it's likely to reduce some failure rates.
Currently the Ranked Robin article claims that the method passes some
fairness criteria that it actually doesn't pass. When the Ranked
Robin article is improved to include a concise description of the
method (which should be near the beginning), some experts here can
identify which of the listed "pass" criteria need to be moved to the
listed "fail" criteria.
Interestingly, the Ranked Robin method and its name were created by
people who have previously promoted only STAR voting. I'm pleased
that they are finally recognizing that STAR ballots are not going to
replace ranked choice ballots throughout the US. And that they
recognize the need to promote a method that takes advantage of the
Forward Party's recommendation of "ranked choice voting."
Looking at the broader perspective ...
The current version of Ranked Robin already has these advantages:
-
Uses pairwise vote counting, which looks deeper into the ballot
preferences compared to instant-runoff voting.
-
Is precinct summable.
-
Allows voters to mark more than one candidate at the same ranking
level.
I suggest making it even easier to understand by using pairwise
support counts. This improvement will eliminate the need to educate
voters about the pairwise matrix. And I believe this change will
still provide a similar level of fairness.
Certainly, in multiple ways, it's much better than instant-runoff voting.
Richard Fobes
The VoteFair guy
Election-Methods mailing list - see https://electorama.com/em for list
info
Election-Methods mailing list - see https://electorama.com/em for list
info
Besides being prone to ties, Copeland also suffers from Clone Dependence,
which makes it inferior to IRV in that regard.
Here are two versions of decloned Copeland that are not prone to ties:
1.Elect the candidate that, on the greatest number of ballots, pairwise
defeats the candidate designated "worst."
That is the burial resistant version of decloned Copeland.
The other version, that may be more appealing to some people, is this:
2. Elect the candidate that, on the fewest number of ballots, is pairwise
defeated by the candidate designated "best."
Both of these methods are monotonic, clone free, and "Round Robin
Efficient."
It is practically impossible for either method to yield a tied result in an
actual political election involving hundreds of ballots.
Because of that fact, the obligatory tie breaker does not need the special
scrutiny that is so important for ordinary clone dependent Copeland.
Random Favorite would be the simplest ... and perfectly adequate tie
breaker.
At the other end of the spectrum, method one could serve as the tie breaker
for method two, and vice-versa.
Between those possibilities there are many others that are also perfectly
adequate.
-Forest
El jue., 31 de mar. de 2022 12:04 p. m., Colin Champion <
colin.champion@routemaster.app> escribió:
> Richard – there are two ways of using a Borda tiebreak, sometimes written
> "Llull//Borda" and "Llull,Borda". It sounds like you understood me to be
> attributing "Llull,Borda" to you while you were actually advocating
> "Llull//Borda". (I have no idea which of these was Dasgupta and Maskin’s
> preference – I don’t think they were clear.) Certainly Llull//Borda reduces
> to a plurality choice between two tied candidates.
> Other tiebreaks (eg. minimax) can be used in the same two ways, which
> is why a fairly general notation exists. I can't say I like it as a
> notation, since it's far from self-explanatory.
> Colin
>
> On 31/03/2022 18:10, Richard, the VoteFair guy wrote:
>
> On 3/30/2022 11:51 PM, Colin Champion wrote:
> > ... is the candidate with the highest support count not the
> > candidate with the highest Borda score? Have you not reinvented
> > Dasgupta-Maskin?
>
> Borda count is a positional voting method:
>
> https://en.wikipedia.org/wiki/Positional_voting
>
> As a tie breaker, only the candidates who are tied are considered in this
> count.
>
> When the tie is between just two candidates, the Borda count would still
> use the (positional) numbers assigned by the voters.
>
> In contrast, I'm recommending a counting method that disregards which
> position contains the mark being counted. So a two-candidate tie becomes
> simple plurality counting.
>
> To repeat, I'm suggesting breaking a tie by using pairwise support
> counts. On one ballot the pairwise support count is the number of
> candidates who are ranked lower than the candidate getting the support
> count. Those counts are added across all the ballots to yield that
> candidate's pairwise support count.
>
> A big advantage is that it can be counted directly from the ballots,
> without first creating a pairwise matrix. Although software would use the
> pairwise matrix approach, voters and the legal description and the
> tabulated results would not mention the pairwise matrix.
>
> Richard Fobes
> The VoteFair guy
>
>
> On 3/30/2022 11:51 PM, Colin Champion wrote:
>
> Richard – is the candidate with the highest support count not the
> candidate with the highest Borda score? Have you not reinvented
> Dasgupta-Maskin?
> Colin
>
>
> On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
>
> Here I'm suggesting a way to improve the recently (fall 2021) created
> "Ranked Robin" method, which is described at Electowiki at this link:
>
> https://electowiki.org/wiki/Ranked_Robin
>
> The improvement is to replace the first-level tie breaker -- which
> looks at margins calculated from the pairwise matrix -- with "pairwise
> support counts" -- which are easily described without using any
> numbers from the pairwise matrix.
>
> Starting from the beginning ...
>
> Currently the Ranked Robin method is described this way:
>
> "Elect the candidate who pairwise beats the greatest number of
> candidates."
>
> That's the method described by Ramon Llull (in 1299).
>
> According to Electowiki that's been improved to become the Copeland
> method, which elects "the candidate with the most (pairwise victories
> minus pairwise defeats)."
>
> According to Wikipedia the Copeland method doesn't do the subtraction
> and instead adds "half the number of candidates with whom he or she
> has a preference tie."
>
> All of these Copeland method variations produce lots of ties.
>
> So of course the Ranked Robin method needs tie breakers. Here's the
> first-level tie breaker as it's currently specified:
>
> "For each finalist, subtract the number of votes preferring each other
> finalist from the number of votes preferring them over each other
> finalist. The finalist with the greatest total difference is elected."
>
> A big disadvantage of this Ranked Robin tie breaker is that it uses
> numbers from the pairwise matrix. Yet one of the stated goals of the
> Ranked Robin method is to avoid confusing voters with the pairwise
> matrix.
>
> Therefore I suggest replacing this tie-breaker method with the use of
> "pairwise support counts." These counts are part of the "Instant
> Pairwise Elimination" (IPE) method, which is described at Electowiki
> at this link:
>
> https://electowiki.org/wiki/Instant_Pairwise_Elimination
>
> It says:
>
> "If an elimination round has no pairwise-losing candidate, then the
> method eliminates the candidate with the largest pairwise opposition
> count, which is determined by counting on each ballot the number of
> not-yet-eliminated candidates who are ranked above that candidate, and
> adding those numbers across all the ballots. If there is a tie for the
> largest pairwise opposition count, the method eliminates the candidate
> with the smallest pairwise support count, which similarly counts
> support rather than opposition. ..."
>
> Of course the second-level tie-breaker would be to use pairwise
> opposition counts. (The pairwise support counts and pairwise
> opposition counts are not always symmetrical.)
>
> Notice that the numbers in the pairwise matrix do not need to be
> mentioned.
>
> Yes, the software will calculate the pairwise support counts from the
> numbers in the pairwise matrix. But that fact doesn't need to be
> mentioned -- to the voters, or in the legal description.
>
> The resulting improved Ranked Robin method can be described as follows:
>
> "The [improved] Ranked Robin method elects the candidate who has the
> most number of one-on-one wins against every other candidate plus half
> the number of one-on-one ties. [*] If more than one candidate has the
> same largest number, the method elects from those tied candidates the
> candidate with the highest pairwise support count. The pairwise
> support count for each of the tied candidates is the sum, across all
> the ballots, of the number of tied [**] candidates who are ranked
> lower than the candidate whose pairwise support count is being counted."
>
> [*] The wording can be adjusted depending on which Copeland variation
> is desired. Adding the words "minus the number of one-on-one losses"
> would specify the other variation.
>
> [**] Importantly, the ballot marks for the non-tied candidates must be
> ignored when resolving the tie.
>
> When the election results are displayed, they might look something
> like this, where the names are from the Ranked Robin article, and the
> numbers don't apply to any particular case:
>
>
> Matchup win and loss counts:
>
> Ava: 4 wins (against ...) and 2 losses (to ...)
>
> Bianca: 4 wins (against ...) and 2 losses (to ...)
>
> Cedric: 3 wins (against ...) and 3 losses (to ...)
>
> Deegan: 3 wins (against ...) and 3 losses (to ...)
>
> Eli: 2 wins (against ...) and 4 losses (to ...)
>
> Fabio: 0 wins and 6 losses
>
>
> The result is a tie between Ava and Bianca because they each have
> 4 wins, and that's more than any other candidate. Considering just
> these tied candidates, their pairwise support counts are:
>
> Ava: 213
>
> Bianca: 123
>
> So Ava wins!
>
>
> Notice there's no need to show a pairwise matrix!
>
> To prevent a potential source of confusion, the Wikipedia article
> about the Borda count begins with the words "The Borda count is a
> family of positional voting rules which gives each candidate, for each
> ballot, a number of points corresponding to the number of candidates
> ranked lower." The last portion of this sentence describes pairwise
> support counts, but it has nothing to do with the Borda count. The
> Wikipedia article for "positional voting" correctly says: "Positional
> voting is a ranked voting electoral system in which the options or
> candidates receive points based on their rank position on each ballot
> and the one with the most points overall wins." The remainder of
> Wikipedia's Borda count article correctly specifies positional voting
> in the descriptions and examples. The Borda count article at
> Electowiki does not include this first-sentence mistake. I'm going to
> let someone else figure out how the first sentence in Wikipedia should
> be worded. (I'd rather fight other battles.)
>
> I'm calling attention to this difference between pairwise support
> counts and the Borda count because this issue has previously caused
> confusion in this forum.
>
> Getting back to the Ranked Robin method, this improved version is not
> likely to significantly increase the failure rates of the most
> important failure criteria, and it's likely to reduce some failure rates.
>
> Currently the Ranked Robin article claims that the method passes some
> fairness criteria that it actually doesn't pass. When the Ranked
> Robin article is improved to include a concise description of the
> method (which should be near the beginning), some experts here can
> identify which of the listed "pass" criteria need to be moved to the
> listed "fail" criteria.
>
> Interestingly, the Ranked Robin method and its name were created by
> people who have previously promoted only STAR voting. I'm pleased
> that they are finally recognizing that STAR ballots are not going to
> replace ranked choice ballots throughout the US. And that they
> recognize the need to promote a method that takes advantage of the
> Forward Party's recommendation of "ranked choice voting."
>
> Looking at the broader perspective ...
>
> The current version of Ranked Robin already has these advantages:
>
> * Uses pairwise vote counting, which looks deeper into the ballot
> preferences compared to instant-runoff voting.
>
> * Is precinct summable.
>
> * Allows voters to mark more than one candidate at the same ranking
> level.
>
> I suggest making it even easier to understand by using pairwise
> support counts. This improvement will eliminate the need to educate
> voters about the pairwise matrix. And I believe this change will
> still provide a similar level of fairness.
>
> Certainly, in multiple ways, it's much better than instant-runoff voting.
>
> Richard Fobes
> The VoteFair guy
> ----
> Election-Methods mailing list - see https://electorama.com/em for list
> info
>
>
>
> ----
> Election-Methods mailing list - see https://electorama.com/em for list
> info
>
KV
Kevin Venzke
Sat, Apr 2, 2022 5:49 AM
Here are two versions of decloned Copeland that are not prone to ties:
1.Elect the candidate that, on the greatest number of ballots, pairwise defeats the candidate designated "worst."
That is the burial resistant version of decloned Copeland.
The other version, that may be more appealing to some people, is this:
2. Elect the candidate that, on the fewest number of ballots, is pairwise defeated by the candidate designated "best."
Both of these methods are monotonic, clone free, and "Round Robin Efficient."
I think I prefer the second one because, if I understand you, the first one doesn't
make sense with truncation.
I'm not sure if I have it correct since I'm having a monotonicity issue. Could you
solve these two elections:
0.333: C>A
0.243: B
0.202: A>B>C>D
0.140: D
0.079: A>C>D>B --> C>A>D>B
It's an A>B>C>A cycle, and D loses to everyone.
The .079 vote change doesn't affect any defeats.
I think C wins and then B wins. What do you think?
Kevin
Hi Forest,
Le vendredi 1 avril 2022, 20:24:25 UTC−5, Forest Simmons <forest.simmons21@gmail.com> a écrit :
> Here are two versions of decloned Copeland that are not prone to ties:
>
> 1.Elect the candidate that, on the greatest number of ballots, pairwise defeats the candidate designated "worst."
>
> That is the burial resistant version of decloned Copeland.
>
> The other version, that may be more appealing to some people, is this:
>
> 2. Elect the candidate that, on the fewest number of ballots, is pairwise defeated by the candidate designated "best."
>
> Both of these methods are monotonic, clone free, and "Round Robin Efficient."
I think I prefer the second one because, if I understand you, the first one doesn't
make sense with truncation.
I'm not sure if I have it correct since I'm having a monotonicity issue. Could you
solve these two elections:
0.333: C>A
0.243: B
0.202: A>B>C>D
0.140: D
0.079: A>C>D>B --> C>A>D>B
It's an A>B>C>A cycle, and D loses to everyone.
The .079 vote change doesn't affect any defeats.
I think C wins and then B wins. What do you think?
Kevin
KM
Kristofer Munsterhjelm
Sat, Apr 2, 2022 9:51 AM
On 02.04.2022 03:24, Forest Simmons wrote:
Besides being prone to ties, Copeland also suffers from Clone
Dependence, which makes it inferior to IRV in that regard.
Here are two versions of decloned Copeland that are not prone to ties:
1.Elect the candidate that, on the greatest number of ballots, pairwise
defeats the candidate designated "worst."
If I'm not mistaken, Stensholt's three-candidate method BPW can be
phrased this way, and I don't think it's monotone. It elects the
candidate who beats the Plurality winner when there's a cycle.
-km
On 02.04.2022 03:24, Forest Simmons wrote:
> Besides being prone to ties, Copeland also suffers from Clone
> Dependence, which makes it inferior to IRV in that regard.
>
> Here are two versions of decloned Copeland that are not prone to ties:
>
> 1.Elect the candidate that, on the greatest number of ballots, pairwise
> defeats the candidate designated "worst."
If I'm not mistaken, Stensholt's three-candidate method BPW can be
phrased this way, and I don't think it's monotone. It elects the
candidate who beats the Plurality winner when there's a cycle.
-km
RT
Richard, the VoteFair guy
Sun, Apr 3, 2022 4:41 AM
On 4/1/2022 6:24 PM, Forest Simmons wrote:
...
Here are two versions of decloned Copeland that are not prone to ties:
1.Elect the candidate that, on the greatest number of ballots,
pairwise defeats the candidate designated "worst."
...
2. Elect the candidate that, on the fewest number of ballots, is
pairwise defeated by the candidate designated "best."
Both of these ways of resolving Copeland ties are more difficult to
understand -- for most voters -- than the current version.
As a further barrier to understanding, these definitions involve
recursion. That's even more difficult to understand than a pairwise matrix.
The goal of the Ranked Robin method (according to the description on
Electowiki) is to provide a method that is reasonably easy to
understand, yet uses ranked choice ballots and yields reasonably fair
results.
As I said, I'm proposing that the method be made even easier to
understand by using pairwise support counts, which are directly
countable from the ballots, without involving a pairwise matrix.
Regarding your desire to protect against clone failures, those are just
one special kind of "irrelevant alternative," as in IIA (independence of
irrelevant alternatives). Personally I'm more concerned about reducing
all kinds of irrelevant alternatives. In this case I'm concerned that
attempts to fully eliminate clone independence failures might have the
side effect of increasing the rates of other kinds of IIA failures.
Richard Fobes
The VoteFair guy
On 4/1/2022 6:24 PM, Forest Simmons wrote:
Besides being prone to ties, Copeland also suffers from Clone
Dependence, which makes it inferior to IRV in that regard.
Here are two versions of decloned Copeland that are not prone to ties:
1.Elect the candidate that, on the greatest number of ballots, pairwise
defeats the candidate designated "worst."
That is the burial resistant version of decloned Copeland.
The other version, that may be more appealing to some people, is this:
- Elect the candidate that, on the fewest number of ballots, is
pairwise defeated by the candidate designated "best."
Both of these methods are monotonic, clone free, and "Round Robin
Efficient."
It is practically impossible for either method to yield a tied result in
an actual political election involving hundreds of ballots.
Because of that fact, the obligatory tie breaker does not need the
special scrutiny that is so important for ordinary clone dependent Copeland.
Random Favorite would be the simplest ... and perfectly adequate tie
breaker.
At the other end of the spectrum, method one could serve as the tie
breaker for method two, and vice-versa.
Between those possibilities there are many others that are also
perfectly adequate.
-Forest
El jue., 31 de mar. de 2022 12:04 p. m., Colin Champion
<colin.champion@routemaster.app mailto:colin.champion@routemaster.app>
escribió:
Richard – there are two ways of using a Borda tiebreak, sometimes
written "Llull//Borda" and "Llull,Borda". It sounds like you
understood me to be attributing "Llull,Borda" to you while you were
actually advocating "Llull//Borda". (I have no idea which of these
was Dasgupta and Maskin’s preference – I don’t think they were
clear.) Certainly Llull//Borda reduces to a plurality choice between
two tied candidates.
Other tiebreaks (eg. minimax) can be used in the same two ways,
which is why a fairly general notation exists. I can't say I like it
as a notation, since it's far from self-explanatory.
Colin
On 31/03/2022 18:10, Richard, the VoteFair guy wrote:
On 3/30/2022 11:51 PM, Colin Champion wrote:
... is the candidate with the highest support count not the
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Borda count is a positional voting method:
https://en.wikipedia.org/wiki/Positional_voting
As a tie breaker, only the candidates who are tied are considered
in this count.
When the tie is between just two candidates, the Borda count would
still use the (positional) numbers assigned by the voters.
In contrast, I'm recommending a counting method that disregards
which position contains the mark being counted. So a
two-candidate tie becomes simple plurality counting.
To repeat, I'm suggesting breaking a tie by using pairwise support
counts. On one ballot the pairwise support count is the number of
candidates who are ranked lower than the candidate getting the
support count. Those counts are added across all the ballots to
yield that candidate's pairwise support count.
A big advantage is that it can be counted directly from the
ballots, without first creating a pairwise matrix. Although
software would use the pairwise matrix approach, voters and the
legal description and the tabulated results would not mention the
pairwise matrix.
Richard Fobes
The VoteFair guy
On 3/30/2022 11:51 PM, Colin Champion wrote:
Richard – is the candidate with the highest support count not the
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Colin
On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
Here I'm suggesting a way to improve the recently (fall 2021)
created
"Ranked Robin" method, which is described at Electowiki at this
link:
https://electowiki.org/wiki/Ranked_Robin
The improvement is to replace the first-level tie breaker -- which
looks at margins calculated from the pairwise matrix -- with
"pairwise
support counts" -- which are easily described without using any
numbers from the pairwise matrix.
Starting from the beginning ...
Currently the Ranked Robin method is described this way:
"Elect the candidate who pairwise beats the greatest number of
candidates."
That's the method described by Ramon Llull (in 1299).
According to Electowiki that's been improved to become the Copeland
method, which elects "the candidate with the most (pairwise
victories
minus pairwise defeats)."
According to Wikipedia the Copeland method doesn't do the
subtraction
and instead adds "half the number of candidates with whom he or she
has a preference tie."
All of these Copeland method variations produce lots of ties.
So of course the Ranked Robin method needs tie breakers. Here's
the
first-level tie breaker as it's currently specified:
"For each finalist, subtract the number of votes preferring each
other
finalist from the number of votes preferring them over each other
finalist. The finalist with the greatest total difference is
elected."
A big disadvantage of this Ranked Robin tie breaker is that it uses
numbers from the pairwise matrix. Yet one of the stated goals
of the
Ranked Robin method is to avoid confusing voters with the pairwise
matrix.
Therefore I suggest replacing this tie-breaker method with the
use of
"pairwise support counts." These counts are part of the "Instant
Pairwise Elimination" (IPE) method, which is described at
Electowiki
at this link:
https://electowiki.org/wiki/Instant_Pairwise_Elimination
It says:
"If an elimination round has no pairwise-losing candidate, then the
method eliminates the candidate with the largest pairwise
opposition
count, which is determined by counting on each ballot the number of
not-yet-eliminated candidates who are ranked above that
candidate, and
adding those numbers across all the ballots. If there is a tie
for the
largest pairwise opposition count, the method eliminates the
candidate
with the smallest pairwise support count, which similarly counts
support rather than opposition. ..."
Of course the second-level tie-breaker would be to use pairwise
opposition counts. (The pairwise support counts and pairwise
opposition counts are not always symmetrical.)
Notice that the numbers in the pairwise matrix do not need to be
mentioned.
Yes, the software will calculate the pairwise support counts
from the
numbers in the pairwise matrix. But that fact doesn't need to be
mentioned -- to the voters, or in the legal description.
The resulting improved Ranked Robin method can be described as
follows:
"The [improved] Ranked Robin method elects the candidate who has
the
most number of one-on-one wins against every other candidate
plus half
the number of one-on-one ties. [*] If more than one candidate
has the
same largest number, the method elects from those tied
candidates the
candidate with the highest pairwise support count. The pairwise
support count for each of the tied candidates is the sum, across
all
the ballots, of the number of tied [**] candidates who are ranked
lower than the candidate whose pairwise support count is being
counted."
[*] The wording can be adjusted depending on which Copeland
variation
is desired. Adding the words "minus the number of one-on-one
losses"
would specify the other variation.
[**] Importantly, the ballot marks for the non-tied candidates
must be
ignored when resolving the tie.
When the election results are displayed, they might look something
like this, where the names are from the Ranked Robin article,
and the
numbers don't apply to any particular case:
Matchup win and loss counts:
Ava: 4 wins (against ...) and 2 losses (to ...)
Bianca: 4 wins (against ...) and 2 losses (to ...)
Cedric: 3 wins (against ...) and 3 losses (to ...)
Deegan: 3 wins (against ...) and 3 losses (to ...)
Eli: 2 wins (against ...) and 4 losses (to ...)
Fabio: 0 wins and 6 losses
The result is a tie between Ava and Bianca because they each
have
4 wins, and that's more than any other candidate. Considering just
these tied candidates, their pairwise support counts are:
Ava: 213
Bianca: 123
So Ava wins!
Notice there's no need to show a pairwise matrix!
To prevent a potential source of confusion, the Wikipedia article
about the Borda count begins with the words "The Borda count is a
family of positional voting rules which gives each candidate,
for each
ballot, a number of points corresponding to the number of
candidates
ranked lower." The last portion of this sentence describes
pairwise
support counts, but it has nothing to do with the Borda count. The
Wikipedia article for "positional voting" correctly says:
"Positional
voting is a ranked voting electoral system in which the options or
candidates receive points based on their rank position on each
ballot
and the one with the most points overall wins." The remainder of
Wikipedia's Borda count article correctly specifies positional
voting
in the descriptions and examples. The Borda count article at
Electowiki does not include this first-sentence mistake. I'm
going to
let someone else figure out how the first sentence in Wikipedia
should
be worded. (I'd rather fight other battles.)
I'm calling attention to this difference between pairwise support
counts and the Borda count because this issue has previously caused
confusion in this forum.
Getting back to the Ranked Robin method, this improved version
is not
likely to significantly increase the failure rates of the most
important failure criteria, and it's likely to reduce some
failure rates.
Currently the Ranked Robin article claims that the method passes
some
fairness criteria that it actually doesn't pass. When the Ranked
Robin article is improved to include a concise description of the
method (which should be near the beginning), some experts here can
identify which of the listed "pass" criteria need to be moved to
the
listed "fail" criteria.
Interestingly, the Ranked Robin method and its name were created by
people who have previously promoted only STAR voting. I'm pleased
that they are finally recognizing that STAR ballots are not
going to
replace ranked choice ballots throughout the US. And that they
recognize the need to promote a method that takes advantage of the
Forward Party's recommendation of "ranked choice voting."
Looking at the broader perspective ...
The current version of Ranked Robin already has these advantages:
* Uses pairwise vote counting, which looks deeper into the ballot
preferences compared to instant-runoff voting.
* Is precinct summable.
* Allows voters to mark more than one candidate at the same ranking
level.
I suggest making it even easier to understand by using pairwise
support counts. This improvement will eliminate the need to
educate
voters about the pairwise matrix. And I believe this change will
still provide a similar level of fairness.
Certainly, in multiple ways, it's much better than
instant-runoff voting.
Richard Fobes
The VoteFair guy
----
Election-Methods mailing list - see https://electorama.com/em
for list
info
----
Election-Methods mailing list - see https://electorama.com/em for
list info
Election-Methods mailing list - see https://electorama.com/em for list info
On 4/1/2022 6:24 PM, Forest Simmons wrote:
> ...
> Here are two versions of decloned Copeland that are not prone to ties:
>
> 1.Elect the candidate that, on the greatest number of ballots,
> pairwise defeats the candidate designated "worst."
> ...
> 2. Elect the candidate that, on the fewest number of ballots, is
> pairwise defeated by the candidate designated "best."
Both of these ways of resolving Copeland ties are more difficult to
understand -- for most voters -- than the current version.
As a further barrier to understanding, these definitions involve
recursion. That's even more difficult to understand than a pairwise matrix.
The goal of the Ranked Robin method (according to the description on
Electowiki) is to provide a method that is reasonably easy to
understand, yet uses ranked choice ballots and yields reasonably fair
results.
As I said, I'm proposing that the method be made even easier to
understand by using pairwise support counts, which are directly
countable from the ballots, without involving a pairwise matrix.
Regarding your desire to protect against clone failures, those are just
one special kind of "irrelevant alternative," as in IIA (independence of
irrelevant alternatives). Personally I'm more concerned about reducing
all kinds of irrelevant alternatives. In this case I'm concerned that
attempts to fully eliminate clone independence failures might have the
side effect of increasing the rates of other kinds of IIA failures.
Richard Fobes
The VoteFair guy
On 4/1/2022 6:24 PM, Forest Simmons wrote:
> Besides being prone to ties, Copeland also suffers from Clone
> Dependence, which makes it inferior to IRV in that regard.
>
> Here are two versions of decloned Copeland that are not prone to ties:
>
> 1.Elect the candidate that, on the greatest number of ballots, pairwise
> defeats the candidate designated "worst."
>
> That is the burial resistant version of decloned Copeland.
>
> The other version, that may be more appealing to some people, is this:
>
> 2. Elect the candidate that, on the fewest number of ballots, is
> pairwise defeated by the candidate designated "best."
>
> Both of these methods are monotonic, clone free, and "Round Robin
> Efficient."
>
> It is practically impossible for either method to yield a tied result in
> an actual political election involving hundreds of ballots.
>
> Because of that fact, the obligatory tie breaker does not need the
> special scrutiny that is so important for ordinary clone dependent Copeland.
>
> Random Favorite would be the simplest ... and perfectly adequate tie
> breaker.
>
> At the other end of the spectrum, method one could serve as the tie
> breaker for method two, and vice-versa.
>
> Between those possibilities there are many others that are also
> perfectly adequate.
>
> -Forest
>
>
>
>
> El jue., 31 de mar. de 2022 12:04 p. m., Colin Champion
> <colin.champion@routemaster.app <mailto:colin.champion@routemaster.app>>
> escribió:
>
> Richard – there are two ways of using a Borda tiebreak, sometimes
> written "Llull//Borda" and "Llull,Borda". It sounds like you
> understood me to be attributing "Llull,Borda" to you while you were
> actually advocating "Llull//Borda". (I have no idea which of these
> was Dasgupta and Maskin’s preference – I don’t think they were
> clear.) Certainly Llull//Borda reduces to a plurality choice between
> two tied candidates.
> Other tiebreaks (eg. minimax) can be used in the same two ways,
> which is why a fairly general notation exists. I can't say I like it
> as a notation, since it's far from self-explanatory.
> Colin
>
> On 31/03/2022 18:10, Richard, the VoteFair guy wrote:
>> On 3/30/2022 11:51 PM, Colin Champion wrote:
>> > ... is the candidate with the highest support count not the
>> > candidate with the highest Borda score? Have you not reinvented
>> > Dasgupta-Maskin?
>>
>> Borda count is a positional voting method:
>>
>> https://en.wikipedia.org/wiki/Positional_voting
>>
>> As a tie breaker, only the candidates who are tied are considered
>> in this count.
>>
>> When the tie is between just two candidates, the Borda count would
>> still use the (positional) numbers assigned by the voters.
>>
>> In contrast, I'm recommending a counting method that disregards
>> which position contains the mark being counted. So a
>> two-candidate tie becomes simple plurality counting.
>>
>> To repeat, I'm suggesting breaking a tie by using pairwise support
>> counts. On one ballot the pairwise support count is the number of
>> candidates who are ranked lower than the candidate getting the
>> support count. Those counts are added across all the ballots to
>> yield that candidate's pairwise support count.
>>
>> A big advantage is that it can be counted directly from the
>> ballots, without first creating a pairwise matrix. Although
>> software would use the pairwise matrix approach, voters and the
>> legal description and the tabulated results would not mention the
>> pairwise matrix.
>>
>> Richard Fobes
>> The VoteFair guy
>>
>>
>> On 3/30/2022 11:51 PM, Colin Champion wrote:
>>> Richard – is the candidate with the highest support count not the
>>> candidate with the highest Borda score? Have you not reinvented
>>> Dasgupta-Maskin?
>>> Colin
>>>
>>>
>>> On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
>>>> Here I'm suggesting a way to improve the recently (fall 2021)
>>>> created
>>>> "Ranked Robin" method, which is described at Electowiki at this
>>>> link:
>>>>
>>>> https://electowiki.org/wiki/Ranked_Robin
>>>>
>>>> The improvement is to replace the first-level tie breaker -- which
>>>> looks at margins calculated from the pairwise matrix -- with
>>>> "pairwise
>>>> support counts" -- which are easily described without using any
>>>> numbers from the pairwise matrix.
>>>>
>>>> Starting from the beginning ...
>>>>
>>>> Currently the Ranked Robin method is described this way:
>>>>
>>>> "Elect the candidate who pairwise beats the greatest number of
>>>> candidates."
>>>>
>>>> That's the method described by Ramon Llull (in 1299).
>>>>
>>>> According to Electowiki that's been improved to become the Copeland
>>>> method, which elects "the candidate with the most (pairwise
>>>> victories
>>>> minus pairwise defeats)."
>>>>
>>>> According to Wikipedia the Copeland method doesn't do the
>>>> subtraction
>>>> and instead adds "half the number of candidates with whom he or she
>>>> has a preference tie."
>>>>
>>>> All of these Copeland method variations produce lots of ties.
>>>>
>>>> So of course the Ranked Robin method needs tie breakers. Here's
>>>> the
>>>> first-level tie breaker as it's currently specified:
>>>>
>>>> "For each finalist, subtract the number of votes preferring each
>>>> other
>>>> finalist from the number of votes preferring them over each other
>>>> finalist. The finalist with the greatest total difference is
>>>> elected."
>>>>
>>>> A big disadvantage of this Ranked Robin tie breaker is that it uses
>>>> numbers from the pairwise matrix. Yet one of the stated goals
>>>> of the
>>>> Ranked Robin method is to avoid confusing voters with the pairwise
>>>> matrix.
>>>>
>>>> Therefore I suggest replacing this tie-breaker method with the
>>>> use of
>>>> "pairwise support counts." These counts are part of the "Instant
>>>> Pairwise Elimination" (IPE) method, which is described at
>>>> Electowiki
>>>> at this link:
>>>>
>>>> https://electowiki.org/wiki/Instant_Pairwise_Elimination
>>>>
>>>> It says:
>>>>
>>>> "If an elimination round has no pairwise-losing candidate, then the
>>>> method eliminates the candidate with the largest pairwise
>>>> opposition
>>>> count, which is determined by counting on each ballot the number of
>>>> not-yet-eliminated candidates who are ranked above that
>>>> candidate, and
>>>> adding those numbers across all the ballots. If there is a tie
>>>> for the
>>>> largest pairwise opposition count, the method eliminates the
>>>> candidate
>>>> with the smallest pairwise support count, which similarly counts
>>>> support rather than opposition. ..."
>>>>
>>>> Of course the second-level tie-breaker would be to use pairwise
>>>> opposition counts. (The pairwise support counts and pairwise
>>>> opposition counts are not always symmetrical.)
>>>>
>>>> Notice that the numbers in the pairwise matrix do not need to be
>>>> mentioned.
>>>>
>>>> Yes, the software will calculate the pairwise support counts
>>>> from the
>>>> numbers in the pairwise matrix. But that fact doesn't need to be
>>>> mentioned -- to the voters, or in the legal description.
>>>>
>>>> The resulting improved Ranked Robin method can be described as
>>>> follows:
>>>>
>>>> "The [improved] Ranked Robin method elects the candidate who has
>>>> the
>>>> most number of one-on-one wins against every other candidate
>>>> plus half
>>>> the number of one-on-one ties. [*] If more than one candidate
>>>> has the
>>>> same largest number, the method elects from those tied
>>>> candidates the
>>>> candidate with the highest pairwise support count. The pairwise
>>>> support count for each of the tied candidates is the sum, across
>>>> all
>>>> the ballots, of the number of tied [**] candidates who are ranked
>>>> lower than the candidate whose pairwise support count is being
>>>> counted."
>>>>
>>>> [*] The wording can be adjusted depending on which Copeland
>>>> variation
>>>> is desired. Adding the words "minus the number of one-on-one
>>>> losses"
>>>> would specify the other variation.
>>>>
>>>> [**] Importantly, the ballot marks for the non-tied candidates
>>>> must be
>>>> ignored when resolving the tie.
>>>>
>>>> When the election results are displayed, they might look something
>>>> like this, where the names are from the Ranked Robin article,
>>>> and the
>>>> numbers don't apply to any particular case:
>>>>
>>>>
>>>> Matchup win and loss counts:
>>>>
>>>> Ava: 4 wins (against ...) and 2 losses (to ...)
>>>>
>>>> Bianca: 4 wins (against ...) and 2 losses (to ...)
>>>>
>>>> Cedric: 3 wins (against ...) and 3 losses (to ...)
>>>>
>>>> Deegan: 3 wins (against ...) and 3 losses (to ...)
>>>>
>>>> Eli: 2 wins (against ...) and 4 losses (to ...)
>>>>
>>>> Fabio: 0 wins and 6 losses
>>>>
>>>>
>>>> The result is a tie between Ava and Bianca because they each
>>>> have
>>>> 4 wins, and that's more than any other candidate. Considering just
>>>> these tied candidates, their pairwise support counts are:
>>>>
>>>> Ava: 213
>>>>
>>>> Bianca: 123
>>>>
>>>> So Ava wins!
>>>>
>>>>
>>>> Notice there's no need to show a pairwise matrix!
>>>>
>>>> To prevent a potential source of confusion, the Wikipedia article
>>>> about the Borda count begins with the words "The Borda count is a
>>>> family of positional voting rules which gives each candidate,
>>>> for each
>>>> ballot, a number of points corresponding to the number of
>>>> candidates
>>>> ranked lower." The last portion of this sentence describes
>>>> pairwise
>>>> support counts, but it has nothing to do with the Borda count. The
>>>> Wikipedia article for "positional voting" correctly says:
>>>> "Positional
>>>> voting is a ranked voting electoral system in which the options or
>>>> candidates receive points based on their rank position on each
>>>> ballot
>>>> and the one with the most points overall wins." The remainder of
>>>> Wikipedia's Borda count article correctly specifies positional
>>>> voting
>>>> in the descriptions and examples. The Borda count article at
>>>> Electowiki does not include this first-sentence mistake. I'm
>>>> going to
>>>> let someone else figure out how the first sentence in Wikipedia
>>>> should
>>>> be worded. (I'd rather fight other battles.)
>>>>
>>>> I'm calling attention to this difference between pairwise support
>>>> counts and the Borda count because this issue has previously caused
>>>> confusion in this forum.
>>>>
>>>> Getting back to the Ranked Robin method, this improved version
>>>> is not
>>>> likely to significantly increase the failure rates of the most
>>>> important failure criteria, and it's likely to reduce some
>>>> failure rates.
>>>>
>>>> Currently the Ranked Robin article claims that the method passes
>>>> some
>>>> fairness criteria that it actually doesn't pass. When the Ranked
>>>> Robin article is improved to include a concise description of the
>>>> method (which should be near the beginning), some experts here can
>>>> identify which of the listed "pass" criteria need to be moved to
>>>> the
>>>> listed "fail" criteria.
>>>>
>>>> Interestingly, the Ranked Robin method and its name were created by
>>>> people who have previously promoted only STAR voting. I'm pleased
>>>> that they are finally recognizing that STAR ballots are not
>>>> going to
>>>> replace ranked choice ballots throughout the US. And that they
>>>> recognize the need to promote a method that takes advantage of the
>>>> Forward Party's recommendation of "ranked choice voting."
>>>>
>>>> Looking at the broader perspective ...
>>>>
>>>> The current version of Ranked Robin already has these advantages:
>>>>
>>>> * Uses pairwise vote counting, which looks deeper into the ballot
>>>> preferences compared to instant-runoff voting.
>>>>
>>>> * Is precinct summable.
>>>>
>>>> * Allows voters to mark more than one candidate at the same ranking
>>>> level.
>>>>
>>>> I suggest making it even easier to understand by using pairwise
>>>> support counts. This improvement will eliminate the need to
>>>> educate
>>>> voters about the pairwise matrix. And I believe this change will
>>>> still provide a similar level of fairness.
>>>>
>>>> Certainly, in multiple ways, it's much better than
>>>> instant-runoff voting.
>>>>
>>>> Richard Fobes
>>>> The VoteFair guy
>>>> ----
>>>> Election-Methods mailing list - see https://electorama.com/em
>>>> for list
>>>> info
>>>
>
> ----
> Election-Methods mailing list - see https://electorama.com/em for
> list info
>
>
>
> ----
> Election-Methods mailing list - see https://electorama.com/em for list info
>
KV
Kevin Venzke
Sun, Apr 3, 2022 9:46 PM
Hi Richard,
You wrote to Forest:
Regarding your desire to protect against clone failures, those are just
one special kind of "irrelevant alternative," as in IIA (independence of
irrelevant alternatives). Personally I'm more concerned about reducing
all kinds of irrelevant alternatives. In this case I'm concerned that
attempts to fully eliminate clone independence failures might have the
side effect of increasing the rates of other kinds of IIA failures.
This is an interesting idea. It's a little hard for me to conceive of why this
would be the case. But clone independence is a difficult standard to meet, and
based on randomly generated scenarios one would likely conclude that "clones,"
as such, are pretty rare. (This sets aside of course the possibility that clones
could be deliberately created as a nomination strategy.)
There are no doubt other approaches we can take to minimize IIA failures.
I see some correlation, via simulations, between compromise incentive and the
potential for "loser withdrawal" to change the outcome. I guess this is not so
surprising since they're conceptually related: A compromising voter likely wants
to pretend that a (expected) losing candidate didn't enter the race at all, in
hopes of getting a better outcome. It's like an "irrelevant alternative" drops
out, but only from some ballots, and only if a certain kind of change can result
from it.
Kevin
Hi Richard,
You wrote to Forest:
> Regarding your desire to protect against clone failures, those are just
> one special kind of "irrelevant alternative," as in IIA (independence of
> irrelevant alternatives). Personally I'm more concerned about reducing
> all kinds of irrelevant alternatives. In this case I'm concerned that
> attempts to fully eliminate clone independence failures might have the
> side effect of increasing the rates of other kinds of IIA failures.
This is an interesting idea. It's a little hard for me to conceive of why this
would be the case. But clone independence is a difficult standard to meet, and
based on randomly generated scenarios one would likely conclude that "clones,"
as such, are pretty rare. (This sets aside of course the possibility that clones
could be deliberately created as a nomination strategy.)
There are no doubt other approaches we can take to minimize IIA failures.
I see some correlation, via simulations, between compromise incentive and the
potential for "loser withdrawal" to change the outcome. I guess this is not so
surprising since they're conceptually related: A compromising voter likely wants
to pretend that a (expected) losing candidate didn't enter the race at all, in
hopes of getting a better outcome. It's like an "irrelevant alternative" drops
out, but only from some ballots, and only if a certain kind of change can result
from it.
Kevin
FS
Forest Simmons
Wed, Apr 6, 2022 4:03 AM
On 4/1/2022 6:24 PM, Forest Simmons wrote:
...
Here are two versions of decloned Copeland that are not prone to ties:
1.Elect the candidate that, on the greatest number of ballots,
pairwise defeats the candidate designated "worst."
...
2. Elect the candidate that, on the fewest number of ballots, is
pairwise defeated by the candidate designated "best."
Both of these ways of resolving Copeland ties are more difficult to
understand -- for most voters -- than the current version.
These are not ways of resolving Copeland ties ... rather they are two
succinctly stated complete versions of Copeland that only vanishingly
rarely require any tie breaker at all, let alone one as elaborate as you
are suggesting.
As a further barrier to understanding, these definitions involve
recursion.
Recursion? Who said recursion? Where did you get that impression? Where is
the recursion in ...
... elect the candidate that, on the fewest number of ballots, is pairwise
defeated by the ballot favorite ....
To spell it out in complete detail ... just open each ballot B and, after
identifying the first preference X on each ballot B, give a demerit to each
candidate Y defeated pairwise by candidate X.
After tallying all of the ballots in this same fashion, elect the candidate
with the fewest demerits.
[That's all there is ... don't try reading something complicated into it
;-)
If another method seems simpler, it's only because you are more familiar
with it.]
A Condorcet candidate will have no demerits because, by definition a
Condorcet candidate is not defeated pairwise.
The key to clone independence is focusing on defeats incurred by the ballot
favorites, rather than giving all pairwise defeats equal weight.
That's even more difficult to procedurally understand than a pairwise
The goal of the Ranked Robin method (according to the description on
Electowiki) is to provide a method that is reasonably easy to
understand, yet uses ranked choice ballots and yields reasonably fair
results.
As I said, I'm proposing that the method be made even easier to
understand by using pairwise support counts, which are directly
countable from the ballots, without involving a pairwise matrix.
Regarding your desire to protect against clone failures, those are just
one special kind of "irrelevant alternative," as in IIA (independence of
irrelevant alternatives). Personally I'm more concerned about reducing
all kinds of irrelevant alternatives. In this case I'm concerned that
attempts to fully eliminate clone independence failures might have the
side effect of increasing the rates of other kinds of IIA failures.
Richard Fobes
The VoteFair guy
On 4/1/2022 6:24 PM, Forest Simmons wrote:
Besides being prone to ties, Copeland also suffers from Clone
Dependence, which makes it inferior to IRV in that regard.
Here are two versions of decloned Copeland that are not prone to ties:
1.Elect the candidate that, on the greatest number of ballots, pairwise
defeats the candidate designated "worst."
That is the burial resistant version of decloned Copeland.
The other version, that may be more appealing to some people, is this:
- Elect the candidate that, on the fewest number of ballots, is
pairwise defeated by the candidate designated "best."
Both of these methods are monotonic, clone free, and "Round Robin
Efficient."
It is practically impossible for either method to yield a tied result in
an actual political election involving hundreds of ballots.
Because of that fact, the obligatory tie breaker does not need the
special scrutiny that is so important for ordinary clone dependent
Random Favorite would be the simplest ... and perfectly adequate tie
breaker.
At the other end of the spectrum, method one could serve as the tie
breaker for method two, and vice-versa.
Between those possibilities there are many others that are also
perfectly adequate.
-Forest
El jue., 31 de mar. de 2022 12:04 p. m., Colin Champion
<colin.champion@routemaster.app mailto:colin.champion@routemaster.app>
escribió:
Richard – there are two ways of using a Borda tiebreak, sometimes
written "Llull//Borda" and "Llull,Borda". It sounds like you
understood me to be attributing "Llull,Borda" to you while you were
actually advocating "Llull//Borda". (I have no idea which of these
was Dasgupta and Maskin’s preference – I don’t think they were
clear.) Certainly Llull//Borda reduces to a plurality choice between
two tied candidates.
Other tiebreaks (eg. minimax) can be used in the same two ways,
which is why a fairly general notation exists. I can't say I like it
as a notation, since it's far from self-explanatory.
Colin
On 31/03/2022 18:10, Richard, the VoteFair guy wrote:
On 3/30/2022 11:51 PM, Colin Champion wrote:
... is the candidate with the highest support count not the
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Borda count is a positional voting method:
https://en.wikipedia.org/wiki/Positional_voting
As a tie breaker, only the candidates who are tied are considered
in this count.
When the tie is between just two candidates, the Borda count would
still use the (positional) numbers assigned by the voters.
In contrast, I'm recommending a counting method that disregards
which position contains the mark being counted. So a
two-candidate tie becomes simple plurality counting.
To repeat, I'm suggesting breaking a tie by using pairwise support
counts. On one ballot the pairwise support count is the number of
candidates who are ranked lower than the candidate getting the
support count. Those counts are added across all the ballots to
yield that candidate's pairwise support count.
A big advantage is that it can be counted directly from the
ballots, without first creating a pairwise matrix. Although
software would use the pairwise matrix approach, voters and the
legal description and the tabulated results would not mention the
pairwise matrix.
Richard Fobes
The VoteFair guy
On 3/30/2022 11:51 PM, Colin Champion wrote:
Richard – is the candidate with the highest support count not the
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Colin
On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
Here I'm suggesting a way to improve the recently (fall 2021)
created
"Ranked Robin" method, which is described at Electowiki at this
link:
https://electowiki.org/wiki/Ranked_Robin
The improvement is to replace the first-level tie breaker -- which
looks at margins calculated from the pairwise matrix -- with
"pairwise
support counts" -- which are easily described without using any
numbers from the pairwise matrix.
Starting from the beginning ...
Currently the Ranked Robin method is described this way:
"Elect the candidate who pairwise beats the greatest number of
candidates."
That's the method described by Ramon Llull (in 1299).
According to Electowiki that's been improved to become the
method, which elects "the candidate with the most (pairwise
victories
minus pairwise defeats)."
According to Wikipedia the Copeland method doesn't do the
subtraction
and instead adds "half the number of candidates with whom he or
has a preference tie."
All of these Copeland method variations produce lots of ties.
So of course the Ranked Robin method needs tie breakers. Here's
the
first-level tie breaker as it's currently specified:
"For each finalist, subtract the number of votes preferring each
other
finalist from the number of votes preferring them over each other
finalist. The finalist with the greatest total difference is
elected."
A big disadvantage of this Ranked Robin tie breaker is that it
numbers from the pairwise matrix. Yet one of the stated goals
of the
Ranked Robin method is to avoid confusing voters with the pairwise
matrix.
Therefore I suggest replacing this tie-breaker method with the
use of
"pairwise support counts." These counts are part of the "Instant
Pairwise Elimination" (IPE) method, which is described at
Electowiki
at this link:
https://electowiki.org/wiki/Instant_Pairwise_Elimination
It says:
"If an elimination round has no pairwise-losing candidate, then
method eliminates the candidate with the largest pairwise
opposition
count, which is determined by counting on each ballot the number
not-yet-eliminated candidates who are ranked above that
candidate, and
adding those numbers across all the ballots. If there is a tie
for the
largest pairwise opposition count, the method eliminates the
candidate
with the smallest pairwise support count, which similarly counts
support rather than opposition. ..."
Of course the second-level tie-breaker would be to use pairwise
opposition counts. (The pairwise support counts and pairwise
opposition counts are not always symmetrical.)
Notice that the numbers in the pairwise matrix do not need to be
mentioned.
Yes, the software will calculate the pairwise support counts
from the
numbers in the pairwise matrix. But that fact doesn't need to be
mentioned -- to the voters, or in the legal description.
The resulting improved Ranked Robin method can be described as
follows:
"The [improved] Ranked Robin method elects the candidate who has
the
most number of one-on-one wins against every other candidate
plus half
the number of one-on-one ties. [*] If more than one candidate
has the
same largest number, the method elects from those tied
candidates the
candidate with the highest pairwise support count. The pairwise
support count for each of the tied candidates is the sum, across
all
the ballots, of the number of tied [**] candidates who are ranked
lower than the candidate whose pairwise support count is being
counted."
[*] The wording can be adjusted depending on which Copeland
variation
is desired. Adding the words "minus the number of one-on-one
losses"
would specify the other variation.
[**] Importantly, the ballot marks for the non-tied candidates
must be
ignored when resolving the tie.
When the election results are displayed, they might look something
like this, where the names are from the Ranked Robin article,
and the
numbers don't apply to any particular case:
Matchup win and loss counts:
Ava: 4 wins (against ...) and 2 losses (to ...)
Bianca: 4 wins (against ...) and 2 losses (to ...)
Cedric: 3 wins (against ...) and 3 losses (to ...)
Deegan: 3 wins (against ...) and 3 losses (to ...)
Eli: 2 wins (against ...) and 4 losses (to ...)
Fabio: 0 wins and 6 losses
The result is a tie between Ava and Bianca because they each
have
4 wins, and that's more than any other candidate. Considering
these tied candidates, their pairwise support counts are:
Ava: 213
Bianca: 123
So Ava wins!
Notice there's no need to show a pairwise matrix!
To prevent a potential source of confusion, the Wikipedia article
about the Borda count begins with the words "The Borda count is a
family of positional voting rules which gives each candidate,
for each
ballot, a number of points corresponding to the number of
candidates
ranked lower." The last portion of this sentence describes
pairwise
support counts, but it has nothing to do with the Borda count.
Wikipedia article for "positional voting" correctly says:
"Positional
voting is a ranked voting electoral system in which the options or
candidates receive points based on their rank position on each
ballot
and the one with the most points overall wins." The remainder of
Wikipedia's Borda count article correctly specifies positional
voting
in the descriptions and examples. The Borda count article at
Electowiki does not include this first-sentence mistake. I'm
going to
let someone else figure out how the first sentence in Wikipedia
should
be worded. (I'd rather fight other battles.)
I'm calling attention to this difference between pairwise support
counts and the Borda count because this issue has previously
confusion in this forum.
Getting back to the Ranked Robin method, this improved version
is not
likely to significantly increase the failure rates of the most
important failure criteria, and it's likely to reduce some
failure rates.
Currently the Ranked Robin article claims that the method passes
some
fairness criteria that it actually doesn't pass. When the Ranked
Robin article is improved to include a concise description of the
method (which should be near the beginning), some experts here can
identify which of the listed "pass" criteria need to be moved to
the
listed "fail" criteria.
Interestingly, the Ranked Robin method and its name were created
people who have previously promoted only STAR voting. I'm pleased
that they are finally recognizing that STAR ballots are not
going to
replace ranked choice ballots throughout the US. And that they
recognize the need to promote a method that takes advantage of the
Forward Party's recommendation of "ranked choice voting."
Looking at the broader perspective ...
The current version of Ranked Robin already has these advantages:
* Uses pairwise vote counting, which looks deeper into the ballot
preferences compared to instant-runoff voting.
* Is precinct summable.
* Allows voters to mark more than one candidate at the same
level.
I suggest making it even easier to understand by using pairwise
support counts. This improvement will eliminate the need to
educate
voters about the pairwise matrix. And I believe this change will
still provide a similar level of fairness.
Certainly, in multiple ways, it's much better than
instant-runoff voting.
Richard Fobes
The VoteFair guy
----
Election-Methods mailing list - see https://electorama.com/em
for list
info
----
Election-Methods mailing list - see https://electorama.com/em for
list info
Election-Methods mailing list - see https://electorama.com/em for list
El sáb., 2 de abr. de 2022 9:41 p. m., Richard, the VoteFair guy <
electionmethods@votefair.org> escribió:
> On 4/1/2022 6:24 PM, Forest Simmons wrote:
> > ...
> > Here are two versions of decloned Copeland that are not prone to ties:
> >
> > 1.Elect the candidate that, on the greatest number of ballots,
> > pairwise defeats the candidate designated "worst."
> > ...
> > 2. Elect the candidate that, on the fewest number of ballots, is
> > pairwise defeated by the candidate designated "best."
>
> Both of these ways of resolving Copeland ties are more difficult to
> understand -- for most voters -- than the current version.
>
These are not ways of resolving Copeland ties ... rather they are two
succinctly stated complete versions of Copeland that only vanishingly
rarely require any tie breaker at all, let alone one as elaborate as you
are suggesting.
>
> As a further barrier to understanding, these definitions involve
> recursion.
Recursion? Who said recursion? Where did you get that impression? Where is
the recursion in ...
... elect the candidate that, on the fewest number of ballots, is pairwise
defeated by the ballot favorite ....
To spell it out in complete detail ... just open each ballot B and, after
identifying the first preference X on each ballot B, give a demerit to each
candidate Y defeated pairwise by candidate X.
After tallying all of the ballots in this same fashion, elect the candidate
with the fewest demerits.
[That's all there is ... don't try reading something complicated into it
;-)
If another method seems simpler, it's only because you are more familiar
with it.]
A Condorcet candidate will have no demerits because, by definition a
Condorcet candidate is not defeated pairwise.
The key to clone independence is focusing on defeats incurred by the ballot
favorites, rather than giving all pairwise defeats equal weight.
That's even more difficult to procedurally understand than a pairwise
> matrix.
> The goal of the Ranked Robin method (according to the description on
> Electowiki) is to provide a method that is reasonably easy to
> understand, yet uses ranked choice ballots and yields reasonably fair
> results.
>
> As I said, I'm proposing that the method be made even easier to
> understand by using pairwise support counts, which are directly
> countable from the ballots, without involving a pairwise matrix.
>
> Regarding your desire to protect against clone failures, those are just
> one special kind of "irrelevant alternative," as in IIA (independence of
> irrelevant alternatives). Personally I'm more concerned about reducing
> all kinds of irrelevant alternatives. In this case I'm concerned that
> attempts to fully eliminate clone independence failures might have the
> side effect of increasing the rates of other kinds of IIA failures.
>
> Richard Fobes
> The VoteFair guy
>
>
> On 4/1/2022 6:24 PM, Forest Simmons wrote:
> > Besides being prone to ties, Copeland also suffers from Clone
> > Dependence, which makes it inferior to IRV in that regard.
> >
> > Here are two versions of decloned Copeland that are not prone to ties:
> >
> > 1.Elect the candidate that, on the greatest number of ballots, pairwise
> > defeats the candidate designated "worst."
> >
> > That is the burial resistant version of decloned Copeland.
> >
> > The other version, that may be more appealing to some people, is this:
> >
> > 2. Elect the candidate that, on the fewest number of ballots, is
> > pairwise defeated by the candidate designated "best."
> >
> > Both of these methods are monotonic, clone free, and "Round Robin
> > Efficient."
> >
> > It is practically impossible for either method to yield a tied result in
> > an actual political election involving hundreds of ballots.
> >
> > Because of that fact, the obligatory tie breaker does not need the
> > special scrutiny that is so important for ordinary clone dependent
> Copeland.
> >
> > Random Favorite would be the simplest ... and perfectly adequate tie
> > breaker.
> >
> > At the other end of the spectrum, method one could serve as the tie
> > breaker for method two, and vice-versa.
> >
> > Between those possibilities there are many others that are also
> > perfectly adequate.
> >
> > -Forest
> >
> >
> >
> >
> > El jue., 31 de mar. de 2022 12:04 p. m., Colin Champion
> > <colin.champion@routemaster.app <mailto:colin.champion@routemaster.app>>
> > escribió:
> >
> > Richard – there are two ways of using a Borda tiebreak, sometimes
> > written "Llull//Borda" and "Llull,Borda". It sounds like you
> > understood me to be attributing "Llull,Borda" to you while you were
> > actually advocating "Llull//Borda". (I have no idea which of these
> > was Dasgupta and Maskin’s preference – I don’t think they were
> > clear.) Certainly Llull//Borda reduces to a plurality choice between
> > two tied candidates.
> > Other tiebreaks (eg. minimax) can be used in the same two ways,
> > which is why a fairly general notation exists. I can't say I like it
> > as a notation, since it's far from self-explanatory.
> > Colin
> >
> > On 31/03/2022 18:10, Richard, the VoteFair guy wrote:
> >> On 3/30/2022 11:51 PM, Colin Champion wrote:
> >> > ... is the candidate with the highest support count not the
> >> > candidate with the highest Borda score? Have you not reinvented
> >> > Dasgupta-Maskin?
> >>
> >> Borda count is a positional voting method:
> >>
> >> https://en.wikipedia.org/wiki/Positional_voting
> >>
> >> As a tie breaker, only the candidates who are tied are considered
> >> in this count.
> >>
> >> When the tie is between just two candidates, the Borda count would
> >> still use the (positional) numbers assigned by the voters.
> >>
> >> In contrast, I'm recommending a counting method that disregards
> >> which position contains the mark being counted. So a
> >> two-candidate tie becomes simple plurality counting.
> >>
> >> To repeat, I'm suggesting breaking a tie by using pairwise support
> >> counts. On one ballot the pairwise support count is the number of
> >> candidates who are ranked lower than the candidate getting the
> >> support count. Those counts are added across all the ballots to
> >> yield that candidate's pairwise support count.
> >>
> >> A big advantage is that it can be counted directly from the
> >> ballots, without first creating a pairwise matrix. Although
> >> software would use the pairwise matrix approach, voters and the
> >> legal description and the tabulated results would not mention the
> >> pairwise matrix.
> >>
> >> Richard Fobes
> >> The VoteFair guy
> >>
> >>
> >> On 3/30/2022 11:51 PM, Colin Champion wrote:
> >>> Richard – is the candidate with the highest support count not the
> >>> candidate with the highest Borda score? Have you not reinvented
> >>> Dasgupta-Maskin?
> >>> Colin
> >>>
> >>>
> >>> On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
> >>>> Here I'm suggesting a way to improve the recently (fall 2021)
> >>>> created
> >>>> "Ranked Robin" method, which is described at Electowiki at this
> >>>> link:
> >>>>
> >>>> https://electowiki.org/wiki/Ranked_Robin
> >>>>
> >>>> The improvement is to replace the first-level tie breaker -- which
> >>>> looks at margins calculated from the pairwise matrix -- with
> >>>> "pairwise
> >>>> support counts" -- which are easily described without using any
> >>>> numbers from the pairwise matrix.
> >>>>
> >>>> Starting from the beginning ...
> >>>>
> >>>> Currently the Ranked Robin method is described this way:
> >>>>
> >>>> "Elect the candidate who pairwise beats the greatest number of
> >>>> candidates."
> >>>>
> >>>> That's the method described by Ramon Llull (in 1299).
> >>>>
> >>>> According to Electowiki that's been improved to become the
> Copeland
> >>>> method, which elects "the candidate with the most (pairwise
> >>>> victories
> >>>> minus pairwise defeats)."
> >>>>
> >>>> According to Wikipedia the Copeland method doesn't do the
> >>>> subtraction
> >>>> and instead adds "half the number of candidates with whom he or
> she
> >>>> has a preference tie."
> >>>>
> >>>> All of these Copeland method variations produce lots of ties.
> >>>>
> >>>> So of course the Ranked Robin method needs tie breakers. Here's
> >>>> the
> >>>> first-level tie breaker as it's currently specified:
> >>>>
> >>>> "For each finalist, subtract the number of votes preferring each
> >>>> other
> >>>> finalist from the number of votes preferring them over each other
> >>>> finalist. The finalist with the greatest total difference is
> >>>> elected."
> >>>>
> >>>> A big disadvantage of this Ranked Robin tie breaker is that it
> uses
> >>>> numbers from the pairwise matrix. Yet one of the stated goals
> >>>> of the
> >>>> Ranked Robin method is to avoid confusing voters with the pairwise
> >>>> matrix.
> >>>>
> >>>> Therefore I suggest replacing this tie-breaker method with the
> >>>> use of
> >>>> "pairwise support counts." These counts are part of the "Instant
> >>>> Pairwise Elimination" (IPE) method, which is described at
> >>>> Electowiki
> >>>> at this link:
> >>>>
> >>>> https://electowiki.org/wiki/Instant_Pairwise_Elimination
> >>>>
> >>>> It says:
> >>>>
> >>>> "If an elimination round has no pairwise-losing candidate, then
> the
> >>>> method eliminates the candidate with the largest pairwise
> >>>> opposition
> >>>> count, which is determined by counting on each ballot the number
> of
> >>>> not-yet-eliminated candidates who are ranked above that
> >>>> candidate, and
> >>>> adding those numbers across all the ballots. If there is a tie
> >>>> for the
> >>>> largest pairwise opposition count, the method eliminates the
> >>>> candidate
> >>>> with the smallest pairwise support count, which similarly counts
> >>>> support rather than opposition. ..."
> >>>>
> >>>> Of course the second-level tie-breaker would be to use pairwise
> >>>> opposition counts. (The pairwise support counts and pairwise
> >>>> opposition counts are not always symmetrical.)
> >>>>
> >>>> Notice that the numbers in the pairwise matrix do not need to be
> >>>> mentioned.
> >>>>
> >>>> Yes, the software will calculate the pairwise support counts
> >>>> from the
> >>>> numbers in the pairwise matrix. But that fact doesn't need to be
> >>>> mentioned -- to the voters, or in the legal description.
> >>>>
> >>>> The resulting improved Ranked Robin method can be described as
> >>>> follows:
> >>>>
> >>>> "The [improved] Ranked Robin method elects the candidate who has
> >>>> the
> >>>> most number of one-on-one wins against every other candidate
> >>>> plus half
> >>>> the number of one-on-one ties. [*] If more than one candidate
> >>>> has the
> >>>> same largest number, the method elects from those tied
> >>>> candidates the
> >>>> candidate with the highest pairwise support count. The pairwise
> >>>> support count for each of the tied candidates is the sum, across
> >>>> all
> >>>> the ballots, of the number of tied [**] candidates who are ranked
> >>>> lower than the candidate whose pairwise support count is being
> >>>> counted."
> >>>>
> >>>> [*] The wording can be adjusted depending on which Copeland
> >>>> variation
> >>>> is desired. Adding the words "minus the number of one-on-one
> >>>> losses"
> >>>> would specify the other variation.
> >>>>
> >>>> [**] Importantly, the ballot marks for the non-tied candidates
> >>>> must be
> >>>> ignored when resolving the tie.
> >>>>
> >>>> When the election results are displayed, they might look something
> >>>> like this, where the names are from the Ranked Robin article,
> >>>> and the
> >>>> numbers don't apply to any particular case:
> >>>>
> >>>>
> >>>> Matchup win and loss counts:
> >>>>
> >>>> Ava: 4 wins (against ...) and 2 losses (to ...)
> >>>>
> >>>> Bianca: 4 wins (against ...) and 2 losses (to ...)
> >>>>
> >>>> Cedric: 3 wins (against ...) and 3 losses (to ...)
> >>>>
> >>>> Deegan: 3 wins (against ...) and 3 losses (to ...)
> >>>>
> >>>> Eli: 2 wins (against ...) and 4 losses (to ...)
> >>>>
> >>>> Fabio: 0 wins and 6 losses
> >>>>
> >>>>
> >>>> The result is a tie between Ava and Bianca because they each
> >>>> have
> >>>> 4 wins, and that's more than any other candidate. Considering
> just
> >>>> these tied candidates, their pairwise support counts are:
> >>>>
> >>>> Ava: 213
> >>>>
> >>>> Bianca: 123
> >>>>
> >>>> So Ava wins!
> >>>>
> >>>>
> >>>> Notice there's no need to show a pairwise matrix!
> >>>>
> >>>> To prevent a potential source of confusion, the Wikipedia article
> >>>> about the Borda count begins with the words "The Borda count is a
> >>>> family of positional voting rules which gives each candidate,
> >>>> for each
> >>>> ballot, a number of points corresponding to the number of
> >>>> candidates
> >>>> ranked lower." The last portion of this sentence describes
> >>>> pairwise
> >>>> support counts, but it has nothing to do with the Borda count.
> The
> >>>> Wikipedia article for "positional voting" correctly says:
> >>>> "Positional
> >>>> voting is a ranked voting electoral system in which the options or
> >>>> candidates receive points based on their rank position on each
> >>>> ballot
> >>>> and the one with the most points overall wins." The remainder of
> >>>> Wikipedia's Borda count article correctly specifies positional
> >>>> voting
> >>>> in the descriptions and examples. The Borda count article at
> >>>> Electowiki does not include this first-sentence mistake. I'm
> >>>> going to
> >>>> let someone else figure out how the first sentence in Wikipedia
> >>>> should
> >>>> be worded. (I'd rather fight other battles.)
> >>>>
> >>>> I'm calling attention to this difference between pairwise support
> >>>> counts and the Borda count because this issue has previously
> caused
> >>>> confusion in this forum.
> >>>>
> >>>> Getting back to the Ranked Robin method, this improved version
> >>>> is not
> >>>> likely to significantly increase the failure rates of the most
> >>>> important failure criteria, and it's likely to reduce some
> >>>> failure rates.
> >>>>
> >>>> Currently the Ranked Robin article claims that the method passes
> >>>> some
> >>>> fairness criteria that it actually doesn't pass. When the Ranked
> >>>> Robin article is improved to include a concise description of the
> >>>> method (which should be near the beginning), some experts here can
> >>>> identify which of the listed "pass" criteria need to be moved to
> >>>> the
> >>>> listed "fail" criteria.
> >>>>
> >>>> Interestingly, the Ranked Robin method and its name were created
> by
> >>>> people who have previously promoted only STAR voting. I'm pleased
> >>>> that they are finally recognizing that STAR ballots are not
> >>>> going to
> >>>> replace ranked choice ballots throughout the US. And that they
> >>>> recognize the need to promote a method that takes advantage of the
> >>>> Forward Party's recommendation of "ranked choice voting."
> >>>>
> >>>> Looking at the broader perspective ...
> >>>>
> >>>> The current version of Ranked Robin already has these advantages:
> >>>>
> >>>> * Uses pairwise vote counting, which looks deeper into the ballot
> >>>> preferences compared to instant-runoff voting.
> >>>>
> >>>> * Is precinct summable.
> >>>>
> >>>> * Allows voters to mark more than one candidate at the same
> ranking
> >>>> level.
> >>>>
> >>>> I suggest making it even easier to understand by using pairwise
> >>>> support counts. This improvement will eliminate the need to
> >>>> educate
> >>>> voters about the pairwise matrix. And I believe this change will
> >>>> still provide a similar level of fairness.
> >>>>
> >>>> Certainly, in multiple ways, it's much better than
> >>>> instant-runoff voting.
> >>>>
> >>>> Richard Fobes
> >>>> The VoteFair guy
> >>>> ----
> >>>> Election-Methods mailing list - see https://electorama.com/em
> >>>> for list
> >>>> info
> >>>
> >
> > ----
> > Election-Methods mailing list - see https://electorama.com/em for
> > list info
> >
> >
> >
> > ----
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> info
> >
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> info
>
RT
Richard, the VoteFair guy
Thu, Apr 7, 2022 9:46 PM
On 4/5/2022 9:03 PM, Forest Simmons wrote:
Recursion? Who said recursion? Where did you get that impression?
Where is the recursion in ...
... elect the candidate that, on the fewest number of ballots,
is pairwise defeated by the ballot favorite ....
Forest, thank you for clarifying that your word "best" refers to "the
ballot favorite."
However, I still don't yet understand how the counting works. How can
any ballot yield a defeat of the candidate who is ranked highest on that
ballot?
For example, suppose there is a ballot:
A > B > C
How would this one ballot be counted?
Specifically, who is "pairwise defeated by the ballot favorite"?
Thanks!
Richard Fobes
The VoteFair guy
On 4/5/2022 9:03 PM, Forest Simmons wrote:
...
Here are two versions of decloned Copeland that are not prone to
1.Elect the candidate that, on the greatest number of ballots,
pairwise defeats the candidate designated "worst."
...
2. Elect the candidate that, on the fewest number of ballots, is
pairwise defeated by the candidate designated "best."
Both of these ways of resolving Copeland ties are more difficult to
understand -- for most voters -- than the current version.
These are not ways of resolving Copeland ties ... rather they are two
succinctly stated complete versions of Copeland that only vanishingly
rarely require any tie breaker at all, let alone one as elaborate as you
are suggesting.
As a further barrier to understanding, these definitions involve
recursion.
Recursion? Who said recursion? Where did you get that impression? Where
is the recursion in ...
... elect the candidate that, on the fewest number of ballots,
is pairwise defeated by the ballot favorite ....
To spell it out in complete detail ... just open each ballot B and,
after identifying the first preference X on each ballot B, give a
demerit to each candidate Y defeated pairwise by candidate X.
After tallying all of the ballots in this same fashion, elect the
candidate with the fewest demerits.
[That's all there is ... don't try reading something complicated into it
;-)
If another method seems simpler, it's only because you are more familiar
with it.]
A Condorcet candidate will have no demerits because, by definition a
Condorcet candidate is not defeated pairwise.
The key to clone independence is focusing on defeats incurred by the
ballot favorites, rather than giving all pairwise defeats equal weight.
That's even more difficult to procedurally understand than a
pairwise matrix.
The goal of the Ranked Robin method (according to the description on
Electowiki) is to provide a method that is reasonably easy to
understand, yet uses ranked choice ballots and yields reasonably fair
results.
As I said, I'm proposing that the method be made even easier to
understand by using pairwise support counts, which are directly
countable from the ballots, without involving a pairwise matrix.
Regarding your desire to protect against clone failures, those are just
one special kind of "irrelevant alternative," as in IIA
(independence of
irrelevant alternatives). Personally I'm more concerned about reducing
all kinds of irrelevant alternatives. In this case I'm concerned that
attempts to fully eliminate clone independence failures might have the
side effect of increasing the rates of other kinds of IIA failures.
Richard Fobes
The VoteFair guy
On 4/1/2022 6:24 PM, Forest Simmons wrote:
Besides being prone to ties, Copeland also suffers from Clone
Dependence, which makes it inferior to IRV in that regard.
Here are two versions of decloned Copeland that are not prone to ties:
1.Elect the candidate that, on the greatest number of ballots,
defeats the candidate designated "worst."
That is the burial resistant version of decloned Copeland.
The other version, that may be more appealing to some people, is this:
- Elect the candidate that, on the fewest number of ballots, is
pairwise defeated by the candidate designated "best."
Both of these methods are monotonic, clone free, and "Round Robin
Efficient."
It is practically impossible for either method to yield a tied
an actual political election involving hundreds of ballots.
Because of that fact, the obligatory tie breaker does not need the
special scrutiny that is so important for ordinary clone dependent
Random Favorite would be the simplest ... and perfectly adequate tie
breaker.
At the other end of the spectrum, method one could serve as the tie
breaker for method two, and vice-versa.
Between those possibilities there are many others that are also
perfectly adequate.
-Forest
El jue., 31 de mar. de 2022 12:04 p. m., Colin Champion
<colin.champion@routemaster.app
<mailto:colin.champion@routemaster.app>
<mailto:colin.champion@routemaster.app
<mailto:colin.champion@routemaster.app>>>
escribió:
Richard – there are two ways of using a Borda tiebreak, sometimes
written "Llull//Borda" and "Llull,Borda". It sounds like you
understood me to be attributing "Llull,Borda" to you while you
actually advocating "Llull//Borda". (I have no idea which of these
was Dasgupta and Maskin’s preference – I don’t think they were
clear.) Certainly Llull//Borda reduces to a plurality choice
two tied candidates.
Other tiebreaks (eg. minimax) can be used in the same two ways,
which is why a fairly general notation exists. I can't say I
as a notation, since it's far from self-explanatory.
Colin
On 31/03/2022 18:10, Richard, the VoteFair guy wrote:
On 3/30/2022 11:51 PM, Colin Champion wrote:
... is the candidate with the highest support count not the
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Borda count is a positional voting method:
https://en.wikipedia.org/wiki/Positional_voting
As a tie breaker, only the candidates who are tied are considered
in this count.
When the tie is between just two candidates, the Borda count
still use the (positional) numbers assigned by the voters.
In contrast, I'm recommending a counting method that disregards
which position contains the mark being counted. So a
two-candidate tie becomes simple plurality counting.
To repeat, I'm suggesting breaking a tie by using pairwise
counts. On one ballot the pairwise support count is the
candidates who are ranked lower than the candidate getting the
support count. Those counts are added across all the ballots to
yield that candidate's pairwise support count.
A big advantage is that it can be counted directly from the
ballots, without first creating a pairwise matrix. Although
software would use the pairwise matrix approach, voters and the
legal description and the tabulated results would not mention the
pairwise matrix.
Richard Fobes
The VoteFair guy
On 3/30/2022 11:51 PM, Colin Champion wrote:
Richard – is the candidate with the highest support count
candidate with the highest Borda score? Have you not reinvented
Dasgupta-Maskin?
Colin
On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
Here I'm suggesting a way to improve the recently (fall 2021)
created
"Ranked Robin" method, which is described at Electowiki at this
link:
https://electowiki.org/wiki/Ranked_Robin
The improvement is to replace the first-level tie breaker
looks at margins calculated from the pairwise matrix -- with
"pairwise
support counts" -- which are easily described without using any
numbers from the pairwise matrix.
Starting from the beginning ...
Currently the Ranked Robin method is described this way:
"Elect the candidate who pairwise beats the greatest number of
candidates."
That's the method described by Ramon Llull (in 1299).
According to Electowiki that's been improved to become the
method, which elects "the candidate with the most (pairwise
victories
minus pairwise defeats)."
According to Wikipedia the Copeland method doesn't do the
subtraction
and instead adds "half the number of candidates with whom
has a preference tie."
All of these Copeland method variations produce lots of ties.
So of course the Ranked Robin method needs tie breakers.
the
first-level tie breaker as it's currently specified:
"For each finalist, subtract the number of votes preferring
other
finalist from the number of votes preferring them over each
finalist. The finalist with the greatest total difference is
elected."
A big disadvantage of this Ranked Robin tie breaker is that
numbers from the pairwise matrix. Yet one of the stated goals
of the
Ranked Robin method is to avoid confusing voters with the
matrix.
Therefore I suggest replacing this tie-breaker method with the
use of
"pairwise support counts." These counts are part of the
Pairwise Elimination" (IPE) method, which is described at
Electowiki
at this link:
https://electowiki.org/wiki/Instant_Pairwise_Elimination
It says:
"If an elimination round has no pairwise-losing candidate,
method eliminates the candidate with the largest pairwise
opposition
count, which is determined by counting on each ballot the
not-yet-eliminated candidates who are ranked above that
candidate, and
adding those numbers across all the ballots. If there is a tie
for the
largest pairwise opposition count, the method eliminates the
candidate
with the smallest pairwise support count, which similarly
support rather than opposition. ..."
Of course the second-level tie-breaker would be to use pairwise
opposition counts. (The pairwise support counts and pairwise
opposition counts are not always symmetrical.)
Notice that the numbers in the pairwise matrix do not need
mentioned.
Yes, the software will calculate the pairwise support counts
from the
numbers in the pairwise matrix. But that fact doesn't need
mentioned -- to the voters, or in the legal description.
The resulting improved Ranked Robin method can be described as
follows:
"The [improved] Ranked Robin method elects the candidate
the
most number of one-on-one wins against every other candidate
plus half
the number of one-on-one ties. [*] If more than one candidate
has the
same largest number, the method elects from those tied
candidates the
candidate with the highest pairwise support count. The
support count for each of the tied candidates is the sum,
all
the ballots, of the number of tied [**] candidates who are
lower than the candidate whose pairwise support count is being
counted."
[*] The wording can be adjusted depending on which Copeland
variation
is desired. Adding the words "minus the number of one-on-one
losses"
would specify the other variation.
[**] Importantly, the ballot marks for the non-tied candidates
must be
ignored when resolving the tie.
When the election results are displayed, they might look
like this, where the names are from the Ranked Robin article,
and the
numbers don't apply to any particular case:
Matchup win and loss counts:
Ava: 4 wins (against ...) and 2 losses (to ...)
Bianca: 4 wins (against ...) and 2 losses (to ...)
Cedric: 3 wins (against ...) and 3 losses (to ...)
Deegan: 3 wins (against ...) and 3 losses (to ...)
Eli: 2 wins (against ...) and 4 losses (to ...)
Fabio: 0 wins and 6 losses
The result is a tie between Ava and Bianca because they
have
4 wins, and that's more than any other candidate.
these tied candidates, their pairwise support counts are:
Ava: 213
Bianca: 123
So Ava wins!
Notice there's no need to show a pairwise matrix!
To prevent a potential source of confusion, the Wikipedia
about the Borda count begins with the words "The Borda
family of positional voting rules which gives each candidate,
for each
ballot, a number of points corresponding to the number of
candidates
ranked lower." The last portion of this sentence describes
pairwise
support counts, but it has nothing to do with the Borda
Wikipedia article for "positional voting" correctly says:
"Positional
voting is a ranked voting electoral system in which the
candidates receive points based on their rank position on each
ballot
and the one with the most points overall wins." The
Wikipedia's Borda count article correctly specifies positional
voting
in the descriptions and examples. The Borda count article at
Electowiki does not include this first-sentence mistake. I'm
going to
let someone else figure out how the first sentence in Wikipedia
should
be worded. (I'd rather fight other battles.)
I'm calling attention to this difference between pairwise
counts and the Borda count because this issue has
confusion in this forum.
Getting back to the Ranked Robin method, this improved version
is not
likely to significantly increase the failure rates of the most
important failure criteria, and it's likely to reduce some
failure rates.
Currently the Ranked Robin article claims that the method
some
fairness criteria that it actually doesn't pass. When the
Robin article is improved to include a concise description
method (which should be near the beginning), some experts
identify which of the listed "pass" criteria need to be
the
listed "fail" criteria.
Interestingly, the Ranked Robin method and its name were
people who have previously promoted only STAR voting. I'm
that they are finally recognizing that STAR ballots are not
going to
replace ranked choice ballots throughout the US. And that they
recognize the need to promote a method that takes advantage
Forward Party's recommendation of "ranked choice voting."
Looking at the broader perspective ...
The current version of Ranked Robin already has these
* Uses pairwise vote counting, which looks deeper into the
preferences compared to instant-runoff voting.
* Is precinct summable.
* Allows voters to mark more than one candidate at the same
level.
I suggest making it even easier to understand by using pairwise
support counts. This improvement will eliminate the need to
educate
voters about the pairwise matrix. And I believe this
still provide a similar level of fairness.
Certainly, in multiple ways, it's much better than
instant-runoff voting.
Richard Fobes
The VoteFair guy
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list info
On 4/5/2022 9:03 PM, Forest Simmons wrote:
> Recursion? Who said recursion? Where did you get that impression?
> Where is the recursion in ...
>
> ... elect the candidate that, on the fewest number of ballots,
> is pairwise defeated by the ballot favorite ....
Forest, thank you for clarifying that your word "best" refers to "the
ballot favorite."
However, I still don't yet understand how the counting works. How can
any ballot yield a defeat of the candidate who is ranked highest on that
ballot?
For example, suppose there is a ballot:
A > B > C
How would this one ballot be counted?
Specifically, who is "pairwise defeated by the ballot favorite"?
Thanks!
Richard Fobes
The VoteFair guy
On 4/5/2022 9:03 PM, Forest Simmons wrote:
>
>
> El sáb., 2 de abr. de 2022 9:41 p. m., Richard, the VoteFair guy
> <electionmethods@votefair.org <mailto:electionmethods@votefair.org>>
> escribió:
>
> On 4/1/2022 6:24 PM, Forest Simmons wrote:
> > ...
> > Here are two versions of decloned Copeland that are not prone to
> ties:
> >
> > 1.Elect the candidate that, on the greatest number of ballots,
> > pairwise defeats the candidate designated "worst."
> > ...
> > 2. Elect the candidate that, on the fewest number of ballots, is
> > pairwise defeated by the candidate designated "best."
>
> Both of these ways of resolving Copeland ties are more difficult to
> understand -- for most voters -- than the current version.
>
>
> These are not ways of resolving Copeland ties ... rather they are two
> succinctly stated complete versions of Copeland that only vanishingly
> rarely require any tie breaker at all, let alone one as elaborate as you
> are suggesting.
>
>
> As a further barrier to understanding, these definitions involve
> recursion.
>
>
> Recursion? Who said recursion? Where did you get that impression? Where
> is the recursion in ...
>
> ... elect the candidate that, on the fewest number of ballots,
> is pairwise defeated by the ballot favorite ....
>
> To spell it out in complete detail ... just open each ballot B and,
> after identifying the first preference X on each ballot B, give a
> demerit to each candidate Y defeated pairwise by candidate X.
>
> After tallying all of the ballots in this same fashion, elect the
> candidate with the fewest demerits.
>
> [That's all there is ... don't try reading something complicated into it
> ;-)
> If another method seems simpler, it's only because you are more familiar
> with it.]
>
> A Condorcet candidate will have no demerits because, by definition a
> Condorcet candidate is not defeated pairwise.
>
> The key to clone independence is focusing on defeats incurred by the
> ballot favorites, rather than giving all pairwise defeats equal weight.
>
>
> That's even more difficult to procedurally understand than a
> pairwise matrix.
>
>
> The goal of the Ranked Robin method (according to the description on
> Electowiki) is to provide a method that is reasonably easy to
> understand, yet uses ranked choice ballots and yields reasonably fair
> results.
>
> As I said, I'm proposing that the method be made even easier to
> understand by using pairwise support counts, which are directly
> countable from the ballots, without involving a pairwise matrix.
>
> Regarding your desire to protect against clone failures, those are just
> one special kind of "irrelevant alternative," as in IIA
> (independence of
> irrelevant alternatives). Personally I'm more concerned about reducing
> all kinds of irrelevant alternatives. In this case I'm concerned that
> attempts to fully eliminate clone independence failures might have the
> side effect of increasing the rates of other kinds of IIA failures.
>
> Richard Fobes
> The VoteFair guy
>
>
> On 4/1/2022 6:24 PM, Forest Simmons wrote:
> > Besides being prone to ties, Copeland also suffers from Clone
> > Dependence, which makes it inferior to IRV in that regard.
> >
> > Here are two versions of decloned Copeland that are not prone to ties:
> >
> > 1.Elect the candidate that, on the greatest number of ballots,
> pairwise
> > defeats the candidate designated "worst."
> >
> > That is the burial resistant version of decloned Copeland.
> >
> > The other version, that may be more appealing to some people, is this:
> >
> > 2. Elect the candidate that, on the fewest number of ballots, is
> > pairwise defeated by the candidate designated "best."
> >
> > Both of these methods are monotonic, clone free, and "Round Robin
> > Efficient."
> >
> > It is practically impossible for either method to yield a tied
> result in
> > an actual political election involving hundreds of ballots.
> >
> > Because of that fact, the obligatory tie breaker does not need the
> > special scrutiny that is so important for ordinary clone dependent
> Copeland.
> >
> > Random Favorite would be the simplest ... and perfectly adequate tie
> > breaker.
> >
> > At the other end of the spectrum, method one could serve as the tie
> > breaker for method two, and vice-versa.
> >
> > Between those possibilities there are many others that are also
> > perfectly adequate.
> >
> > -Forest
> >
> >
> >
> >
> > El jue., 31 de mar. de 2022 12:04 p. m., Colin Champion
> > <colin.champion@routemaster.app
> <mailto:colin.champion@routemaster.app>
> <mailto:colin.champion@routemaster.app
> <mailto:colin.champion@routemaster.app>>>
> > escribió:
> >
> > Richard – there are two ways of using a Borda tiebreak, sometimes
> > written "Llull//Borda" and "Llull,Borda". It sounds like you
> > understood me to be attributing "Llull,Borda" to you while you
> were
> > actually advocating "Llull//Borda". (I have no idea which of these
> > was Dasgupta and Maskin’s preference – I don’t think they were
> > clear.) Certainly Llull//Borda reduces to a plurality choice
> between
> > two tied candidates.
> > Other tiebreaks (eg. minimax) can be used in the same two ways,
> > which is why a fairly general notation exists. I can't say I
> like it
> > as a notation, since it's far from self-explanatory.
> > Colin
> >
> > On 31/03/2022 18:10, Richard, the VoteFair guy wrote:
> >> On 3/30/2022 11:51 PM, Colin Champion wrote:
> >> > ... is the candidate with the highest support count not the
> >> > candidate with the highest Borda score? Have you not reinvented
> >> > Dasgupta-Maskin?
> >>
> >> Borda count is a positional voting method:
> >>
> >> https://en.wikipedia.org/wiki/Positional_voting
> >>
> >> As a tie breaker, only the candidates who are tied are considered
> >> in this count.
> >>
> >> When the tie is between just two candidates, the Borda count
> would
> >> still use the (positional) numbers assigned by the voters.
> >>
> >> In contrast, I'm recommending a counting method that disregards
> >> which position contains the mark being counted. So a
> >> two-candidate tie becomes simple plurality counting.
> >>
> >> To repeat, I'm suggesting breaking a tie by using pairwise
> support
> >> counts. On one ballot the pairwise support count is the
> number of
> >> candidates who are ranked lower than the candidate getting the
> >> support count. Those counts are added across all the ballots to
> >> yield that candidate's pairwise support count.
> >>
> >> A big advantage is that it can be counted directly from the
> >> ballots, without first creating a pairwise matrix. Although
> >> software would use the pairwise matrix approach, voters and the
> >> legal description and the tabulated results would not mention the
> >> pairwise matrix.
> >>
> >> Richard Fobes
> >> The VoteFair guy
> >>
> >>
> >> On 3/30/2022 11:51 PM, Colin Champion wrote:
> >>> Richard – is the candidate with the highest support count
> not the
> >>> candidate with the highest Borda score? Have you not reinvented
> >>> Dasgupta-Maskin?
> >>> Colin
> >>>
> >>>
> >>> On 31/03/2022 05:58, Richard, the VoteFair guy wrote:
> >>>> Here I'm suggesting a way to improve the recently (fall 2021)
> >>>> created
> >>>> "Ranked Robin" method, which is described at Electowiki at this
> >>>> link:
> >>>>
> >>>> https://electowiki.org/wiki/Ranked_Robin
> >>>>
> >>>> The improvement is to replace the first-level tie breaker
> -- which
> >>>> looks at margins calculated from the pairwise matrix -- with
> >>>> "pairwise
> >>>> support counts" -- which are easily described without using any
> >>>> numbers from the pairwise matrix.
> >>>>
> >>>> Starting from the beginning ...
> >>>>
> >>>> Currently the Ranked Robin method is described this way:
> >>>>
> >>>> "Elect the candidate who pairwise beats the greatest number of
> >>>> candidates."
> >>>>
> >>>> That's the method described by Ramon Llull (in 1299).
> >>>>
> >>>> According to Electowiki that's been improved to become the
> Copeland
> >>>> method, which elects "the candidate with the most (pairwise
> >>>> victories
> >>>> minus pairwise defeats)."
> >>>>
> >>>> According to Wikipedia the Copeland method doesn't do the
> >>>> subtraction
> >>>> and instead adds "half the number of candidates with whom
> he or she
> >>>> has a preference tie."
> >>>>
> >>>> All of these Copeland method variations produce lots of ties.
> >>>>
> >>>> So of course the Ranked Robin method needs tie breakers.
> Here's
> >>>> the
> >>>> first-level tie breaker as it's currently specified:
> >>>>
> >>>> "For each finalist, subtract the number of votes preferring
> each
> >>>> other
> >>>> finalist from the number of votes preferring them over each
> other
> >>>> finalist. The finalist with the greatest total difference is
> >>>> elected."
> >>>>
> >>>> A big disadvantage of this Ranked Robin tie breaker is that
> it uses
> >>>> numbers from the pairwise matrix. Yet one of the stated goals
> >>>> of the
> >>>> Ranked Robin method is to avoid confusing voters with the
> pairwise
> >>>> matrix.
> >>>>
> >>>> Therefore I suggest replacing this tie-breaker method with the
> >>>> use of
> >>>> "pairwise support counts." These counts are part of the
> "Instant
> >>>> Pairwise Elimination" (IPE) method, which is described at
> >>>> Electowiki
> >>>> at this link:
> >>>>
> >>>> https://electowiki.org/wiki/Instant_Pairwise_Elimination
> >>>>
> >>>> It says:
> >>>>
> >>>> "If an elimination round has no pairwise-losing candidate,
> then the
> >>>> method eliminates the candidate with the largest pairwise
> >>>> opposition
> >>>> count, which is determined by counting on each ballot the
> number of
> >>>> not-yet-eliminated candidates who are ranked above that
> >>>> candidate, and
> >>>> adding those numbers across all the ballots. If there is a tie
> >>>> for the
> >>>> largest pairwise opposition count, the method eliminates the
> >>>> candidate
> >>>> with the smallest pairwise support count, which similarly
> counts
> >>>> support rather than opposition. ..."
> >>>>
> >>>> Of course the second-level tie-breaker would be to use pairwise
> >>>> opposition counts. (The pairwise support counts and pairwise
> >>>> opposition counts are not always symmetrical.)
> >>>>
> >>>> Notice that the numbers in the pairwise matrix do not need
> to be
> >>>> mentioned.
> >>>>
> >>>> Yes, the software will calculate the pairwise support counts
> >>>> from the
> >>>> numbers in the pairwise matrix. But that fact doesn't need
> to be
> >>>> mentioned -- to the voters, or in the legal description.
> >>>>
> >>>> The resulting improved Ranked Robin method can be described as
> >>>> follows:
> >>>>
> >>>> "The [improved] Ranked Robin method elects the candidate
> who has
> >>>> the
> >>>> most number of one-on-one wins against every other candidate
> >>>> plus half
> >>>> the number of one-on-one ties. [*] If more than one candidate
> >>>> has the
> >>>> same largest number, the method elects from those tied
> >>>> candidates the
> >>>> candidate with the highest pairwise support count. The
> pairwise
> >>>> support count for each of the tied candidates is the sum,
> across
> >>>> all
> >>>> the ballots, of the number of tied [**] candidates who are
> ranked
> >>>> lower than the candidate whose pairwise support count is being
> >>>> counted."
> >>>>
> >>>> [*] The wording can be adjusted depending on which Copeland
> >>>> variation
> >>>> is desired. Adding the words "minus the number of one-on-one
> >>>> losses"
> >>>> would specify the other variation.
> >>>>
> >>>> [**] Importantly, the ballot marks for the non-tied candidates
> >>>> must be
> >>>> ignored when resolving the tie.
> >>>>
> >>>> When the election results are displayed, they might look
> something
> >>>> like this, where the names are from the Ranked Robin article,
> >>>> and the
> >>>> numbers don't apply to any particular case:
> >>>>
> >>>>
> >>>> Matchup win and loss counts:
> >>>>
> >>>> Ava: 4 wins (against ...) and 2 losses (to ...)
> >>>>
> >>>> Bianca: 4 wins (against ...) and 2 losses (to ...)
> >>>>
> >>>> Cedric: 3 wins (against ...) and 3 losses (to ...)
> >>>>
> >>>> Deegan: 3 wins (against ...) and 3 losses (to ...)
> >>>>
> >>>> Eli: 2 wins (against ...) and 4 losses (to ...)
> >>>>
> >>>> Fabio: 0 wins and 6 losses
> >>>>
> >>>>
> >>>> The result is a tie between Ava and Bianca because they
> each
> >>>> have
> >>>> 4 wins, and that's more than any other candidate.
> Considering just
> >>>> these tied candidates, their pairwise support counts are:
> >>>>
> >>>> Ava: 213
> >>>>
> >>>> Bianca: 123
> >>>>
> >>>> So Ava wins!
> >>>>
> >>>>
> >>>> Notice there's no need to show a pairwise matrix!
> >>>>
> >>>> To prevent a potential source of confusion, the Wikipedia
> article
> >>>> about the Borda count begins with the words "The Borda
> count is a
> >>>> family of positional voting rules which gives each candidate,
> >>>> for each
> >>>> ballot, a number of points corresponding to the number of
> >>>> candidates
> >>>> ranked lower." The last portion of this sentence describes
> >>>> pairwise
> >>>> support counts, but it has nothing to do with the Borda
> count. The
> >>>> Wikipedia article for "positional voting" correctly says:
> >>>> "Positional
> >>>> voting is a ranked voting electoral system in which the
> options or
> >>>> candidates receive points based on their rank position on each
> >>>> ballot
> >>>> and the one with the most points overall wins." The
> remainder of
> >>>> Wikipedia's Borda count article correctly specifies positional
> >>>> voting
> >>>> in the descriptions and examples. The Borda count article at
> >>>> Electowiki does not include this first-sentence mistake. I'm
> >>>> going to
> >>>> let someone else figure out how the first sentence in Wikipedia
> >>>> should
> >>>> be worded. (I'd rather fight other battles.)
> >>>>
> >>>> I'm calling attention to this difference between pairwise
> support
> >>>> counts and the Borda count because this issue has
> previously caused
> >>>> confusion in this forum.
> >>>>
> >>>> Getting back to the Ranked Robin method, this improved version
> >>>> is not
> >>>> likely to significantly increase the failure rates of the most
> >>>> important failure criteria, and it's likely to reduce some
> >>>> failure rates.
> >>>>
> >>>> Currently the Ranked Robin article claims that the method
> passes
> >>>> some
> >>>> fairness criteria that it actually doesn't pass. When the
> Ranked
> >>>> Robin article is improved to include a concise description
> of the
> >>>> method (which should be near the beginning), some experts
> here can
> >>>> identify which of the listed "pass" criteria need to be
> moved to
> >>>> the
> >>>> listed "fail" criteria.
> >>>>
> >>>> Interestingly, the Ranked Robin method and its name were
> created by
> >>>> people who have previously promoted only STAR voting. I'm
> pleased
> >>>> that they are finally recognizing that STAR ballots are not
> >>>> going to
> >>>> replace ranked choice ballots throughout the US. And that they
> >>>> recognize the need to promote a method that takes advantage
> of the
> >>>> Forward Party's recommendation of "ranked choice voting."
> >>>>
> >>>> Looking at the broader perspective ...
> >>>>
> >>>> The current version of Ranked Robin already has these
> advantages:
> >>>>
> >>>> * Uses pairwise vote counting, which looks deeper into the
> ballot
> >>>> preferences compared to instant-runoff voting.
> >>>>
> >>>> * Is precinct summable.
> >>>>
> >>>> * Allows voters to mark more than one candidate at the same
> ranking
> >>>> level.
> >>>>
> >>>> I suggest making it even easier to understand by using pairwise
> >>>> support counts. This improvement will eliminate the need to
> >>>> educate
> >>>> voters about the pairwise matrix. And I believe this
> change will
> >>>> still provide a similar level of fairness.
> >>>>
> >>>> Certainly, in multiple ways, it's much better than
> >>>> instant-runoff voting.
> >>>>
> >>>> Richard Fobes
> >>>> The VoteFair guy
> >>>> ----
> >>>> Election-Methods mailing list - see https://electorama.com/em
> >>>> for list
> >>>> info
> >>>
> >
> > ----
> > Election-Methods mailing list - see https://electorama.com/em for
> > list info
> >
> >
> >
> > ----
> > Election-Methods mailing list - see https://electorama.com/em for
> list info
> >
> ----
> Election-Methods mailing list - see https://electorama.com/em for
> list info
>