Score Then Automatic Runoff (STAR) elects the pairwise winner between the
two candidates with the highest score totals.
One of the biggest problems with this method is that there is an
appreciable likelihood that the winner W will be a candidate that is
pairwise dominated by some other candidate C, which means that C not only
scores higher than W on more ballots than not, but if there even exists a
beatpath from W back to C, it will take at least three steps.
Most other extant methods have this same defect, but almost all of them are
hard to fix compared to STAR. This fact makes it easy for a tweaked version
of STAR to become arguably superior to any of these other methods.
Usually step 2 will be invoked only one or two times if at all ... so this
is not a big tweak.
With this tweak STAR becomes arguably superior to any method currently in
use.
The only other method currently in use that always elects pairwise
undominated candidates is Copeland. But Copeland suffers from two fatal
defect that STAR does not have ... Copeland is neither Decisive nor Clone
Independent.
Will STAR proponents take advantage of this opportunity? ... or will they
pass it up?
fws
Wouldn't it be simpler (and better?) to start with the score winner rather than the STAR winner?
What do you mean by pairwise dominate in this context? I presume from the context (when you talk about Copeland) it's not the same as pairwise beat. Are you talking about covering in the Landau sense?
On Friday, 11 August 2023 at 01:19:30 BST, Forest Simmons forest.simmons21@gmail.com wrote:
Score Then Automatic Runoff (STAR) elects the pairwise winner between the two candidates with the highest score totals.
One of the biggest problems with this method is that there is an appreciable likelihood that the winner W will be a candidate that is pairwise dominated by some other candidate C, which means that C not only scores higher than W on more ballots than not, but if there even exists a beatpath from W back to C, it will take at least three steps.
Most other extant methods have this same defect, but almost all of them are hard to fix compared to STAR. This fact makes it easy for a tweaked version of STAR to become arguably superior to any of these other methods.
That would be simpler, but not as diplomatic.
You could initialize the chain with the winner of anybody's favorite
method, but ideally it would be a monotone clone independen method.
Pairwise Dominate is another (more descriptive way to say "cover" ... which
I defined as the opposite of not being Pairwise Dominated.... we want our
winner to be undominsted pairwise ... which can be easily checked as I
suggested by the existence of a short return beatpath to any challenger.
On Fri, Aug 11, 2023, 5:19 AM Toby Pereira tdp201b@yahoo.co.uk wrote:
Wouldn't it be simpler (and better?) to start with the score winner rather
than the STAR winner?
What do you mean by pairwise dominate in this context? I presume from the
context (when you talk about Copeland) it's not the same as pairwise beat.
Are you talking about covering in the Landau sense?
On Friday, 11 August 2023 at 01:19:30 BST, Forest Simmons <
forest.simmons21@gmail.com> wrote:
Score Then Automatic Runoff (STAR) elects the pairwise winner between the
two candidates with the highest score totals.
One of the biggest problems with this method is that there is an
appreciable likelihood that the winner W will be a candidate that is
pairwise dominated by some other candidate C, which means that C not only
scores higher than W on more ballots than not, but if there even exists a
beatpath from W back to C, it will take at least three steps.
Most other extant methods have this same defect, but almost all of them
are hard to fix compared to STAR. This fact makes it easy for a tweaked
version of STAR to become arguably superior to any of these other methods.
Usually step 2 will be invoked only one or two times if at all ... so this
is not a big tweak.
With this tweak STAR becomes arguably superior to any method currently in
use.
The only other method currently in use that always elects pairwise
undominated candidates is Copeland. But Copeland suffers from two fatal
defect that STAR does not have ... Copeland is neither Decisive nor Clone
Independent.
Will STAR proponents take advantage of this opportunity? ... or will they
pass it up?
Election-Methods mailing list - see https://electorama.com/em for list
info
Forest
I'm not sure it would be undiplomatic to start with the score winner. The top two run-off in STAR is the second stage to complete the method after doing score voting. By saying that it needs further completion is doing away with STAR's completion anyway, and to have three stages seems unnecessarily unwieldy and more likely to throw out strange results. STAR is also not clone independent, so this goes against your stated preference. This is just another way to complete the method instead of STAR, so I think it makes sense to start with the score winner, rather than the STAR winner.
Toby
On Sunday, 13 August 2023 at 00:12:21 BST, Forest Simmons forest.simmons21@gmail.com wrote:
That would be simpler, but not as diplomatic.
You could initialize the chain with the winner of anybody's favorite method, but ideally it would be a monotone clone independen method.
Pairwise Dominate is another (more descriptive way to say "cover" ... which I defined as the opposite of not being Pairwise Dominated.... we want our winner to be undominsted pairwise ... which can be easily checked as I suggested by the existence of a short return beatpath to any challenger.
On Fri, Aug 11, 2023, 5:19 AM Toby Pereira tdp201b@yahoo.co.uk wrote:
Wouldn't it be simpler (and better?) to start with the score winner rather than the STAR winner?
What do you mean by pairwise dominate in this context? I presume from the context (when you talk about Copeland) it's not the same as pairwise beat. Are you talking about covering in the Landau sense?
On Friday, 11 August 2023 at 01:19:30 BST, Forest Simmons forest.simmons21@gmail.com wrote:
Score Then Automatic Runoff (STAR) elects the pairwise winner between the two candidates with the highest score totals.
One of the biggest problems with this method is that there is an appreciable likelihood that the winner W will be a candidate that is pairwise dominated by some other candidate C, which means that C not only scores higher than W on more ballots than not, but if there even exists a beatpath from W back to C, it will take at least three steps.
Most other extant methods have this same defect, but almost all of them are hard to fix compared to STAR. This fact makes it easy for a tweaked version of STAR to become arguably superior to any of these other methods.
By the way, if you started with the score winner, would it just be Landau//Score?
Toby
On Saturday, 19 August 2023 at 21:37:23 BST, Toby Pereira tdp201b@yahoo.co.uk wrote:
Forest
I'm not sure it would be undiplomatic to start with the score winner. The top two run-off in STAR is the second stage to complete the method after doing score voting. By saying that it needs further completion is doing away with STAR's completion anyway, and to have three stages seems unnecessarily unwieldy and more likely to throw out strange results. STAR is also not clone independent, so this goes against your stated preference. This is just another way to complete the method instead of STAR, so I think it makes sense to start with the score winner, rather than the STAR winner.
Toby
On Sunday, 13 August 2023 at 00:12:21 BST, Forest Simmons forest.simmons21@gmail.com wrote:
That would be simpler, but not as diplomatic.
You could initialize the chain with the winner of anybody's favorite method, but ideally it would be a monotone clone independen method.
Pairwise Dominate is another (more descriptive way to say "cover" ... which I defined as the opposite of not being Pairwise Dominated.... we want our winner to be undominsted pairwise ... which can be easily checked as I suggested by the existence of a short return beatpath to any challenger.
On Fri, Aug 11, 2023, 5:19 AM Toby Pereira tdp201b@yahoo.co.uk wrote:
Wouldn't it be simpler (and better?) to start with the score winner rather than the STAR winner?
What do you mean by pairwise dominate in this context? I presume from the context (when you talk about Copeland) it's not the same as pairwise beat. Are you talking about covering in the Landau sense?
On Friday, 11 August 2023 at 01:19:30 BST, Forest Simmons forest.simmons21@gmail.com wrote:
Score Then Automatic Runoff (STAR) elects the pairwise winner between the two candidates with the highest score totals.
One of the biggest problems with this method is that there is an appreciable likelihood that the winner W will be a candidate that is pairwise dominated by some other candidate C, which means that C not only scores higher than W on more ballots than not, but if there even exists a beatpath from W back to C, it will take at least three steps.
Most other extant methods have this same defect, but almost all of them are hard to fix compared to STAR. This fact makes it easy for a tweaked version of STAR to become arguably superior to any of these other methods.
It turns out that electing the highest score Landau candidate fails mono
raise. Same thing for Banks, which is why it is non trivial to get
monotonic Landau and Banks efficient methods.
On Mon, Aug 21, 2023, 5:42 AM Toby Pereira tdp201b@yahoo.co.uk wrote:
By the way, if you started with the score winner, would it just be
Landau//Score?
Toby
On Saturday, 19 August 2023 at 21:37:23 BST, Toby Pereira <
tdp201b@yahoo.co.uk> wrote:
Forest
I'm not sure it would be undiplomatic to start with the score winner. The
top two run-off in STAR is the second stage to complete the method after
doing score voting. By saying that it needs further completion is doing
away with STAR's completion anyway, and to have three stages seems
unnecessarily unwieldy and more likely to throw out strange results. STAR
is also not clone independent, so this goes against your stated preference.
This is just another way to complete the method instead of STAR, so I think
it makes sense to start with the score winner, rather than the STAR winner.
Toby
On Sunday, 13 August 2023 at 00:12:21 BST, Forest Simmons <
forest.simmons21@gmail.com> wrote:
That would be simpler, but not as diplomatic.
You could initialize the chain with the winner of anybody's favorite
method, but ideally it would be a monotone clone independen method.
Pairwise Dominate is another (more descriptive way to say "cover" ...
which I defined as the opposite of not being Pairwise Dominated.... we want
our winner to be undominsted pairwise ... which can be easily checked as I
suggested by the existence of a short return beatpath to any challenger.
On Fri, Aug 11, 2023, 5:19 AM Toby Pereira tdp201b@yahoo.co.uk wrote:
Wouldn't it be simpler (and better?) to start with the score winner rather
than the STAR winner?
What do you mean by pairwise dominate in this context? I presume from the
context (when you talk about Copeland) it's not the same as pairwise beat.
Are you talking about covering in the Landau sense?
On Friday, 11 August 2023 at 01:19:30 BST, Forest Simmons <
forest.simmons21@gmail.com> wrote:
Score Then Automatic Runoff (STAR) elects the pairwise winner between the
two candidates with the highest score totals.
One of the biggest problems with this method is that there is an
appreciable likelihood that the winner W will be a candidate that is
pairwise dominated by some other candidate C, which means that C not only
scores higher than W on more ballots than not, but if there even exists a
beatpath from W back to C, it will take at least three steps.
Most other extant methods have this same defect, but almost all of them
are hard to fix compared to STAR. This fact makes it easy for a tweaked
version of STAR to become arguably superior to any of these other methods.
Usually step 2 will be invoked only one or two times if at all ... so this
is not a big tweak.
With this tweak STAR becomes arguably superior to any method currently in
use.
The only other method currently in use that always elects pairwise
undominated candidates is Copeland. But Copeland suffers from two fatal
defect that STAR does not have ... Copeland is neither Decisive nor Clone
Independent.
Will STAR proponents take advantage of this opportunity? ... or will they
pass it up?
Election-Methods mailing list - see https://electorama.com/em for list
info