In defence of IRV
Forrest wrote: "If people interested in voting methods reform would take
the time to digest these basic facts .... they would never accept any
'ranked choice voting' method unless it satisfied the Condorcet
Criterion." I think that a defence can be offered for people who reject
the Condorcet principle.
Firstly, some published evaluations show no appreciable difference in
performance between Condorcet methods and IRV. In Tideman and
Plassmann's 2012 paper, Table 1 appears to show that when the number of
voters is large, Condorcet methods are 94.46% accurate and AV/IRV is
94.41% accurate. A twentieth of a percent difference! In Table 2 of
Green-Armytage et al (2015) you get similar numbers: Minimax is 95.19%
accurate and "Hare" 94.45%. If the difference really is that small, then
IRV has the advantage of known resistance to tactical voting and has the
benefit of having been widely used in practice. There should be no
argument that IRV is the way to go.
In my view there are two weaknesses with this argument. I think (i) that
having 3 candidates in a multidimensional space makes the problem
unrealistically easy, and (ii) - notwithstanding (i) - that these
results could only have been produced by buggy software. I'll say more
about this later. But Tideman is probably the most respected worker in
the field. You can't argue against IRV if you don't admit that his
evaluations have been seriously misleading.
Secondly, it seems to me that supporters of IRV generally acknowledge
the defects of their method (while probably not being aware of their
magnitude). They consider that at least IRV has a realistic chance of
adoption. They point to the fact that their critics are divided into
1000 factions, that they attach too much importance to theological
arguments about logical criteria, and that they often end up advocating
unrealistic methods. This allows Condorcet supporters to be portrayed as
lacking social responsibilty: see
https://rangevoting.org/SchulzeComplic.html.
Finally, voting methods are generally part of larger electoral systems,
and decisiveness is often as important as fairness. In the UK, electoral
reformers start off thinking they have irresistable logical arguments,
and end up getting bogged down in unwinnable debates about the need for
'firm government'. (I can say nothing about the USA, whose institutions
I don't understand.) Unless you can argue that a change of voting method
will not do more harm through indecisiveness than it does good through
fairness, you haven't really got an argument in favour of Condorcet methods.
On evaluations. The Median Voter Theorem (which I think Forrest was
alluding to) predicts that if a large number of voters come from a
symmetric distribution (eg Gaussian), then all Condorcet methods will
elect the candidate closest to the point in space which minimises the
sum of distances to voters (ie. the centre of the distribution). This is
not quite the same as electing the candidate who minimises the sum of
distances to voters, who will be identified as the rightful winner under
standard evaluation procedures. But the difference is tiny, and cannot
account for the 5% error rate attributed to Condorcet methods by Tideman
and his coworkers.
I described an evaluation of my own in a previous post. I used Gaussian
mixture models instead of pure Gaussians precisely in order to escape
from the Median Voter Theorem; otherwise the Condorcet systems would
have been indistinguishable from each other. But it's a trivial change
to revert to a single Gaussian. When I do so, the accuracy of Condorcet
methods is 99.73% and that of IRV is 95.81% (3 candidates, 30001 voters,
a million trials). Similar to Tideman et al for IRV; totally different
for Condorcet.
Now see what happens when we go up to 9 candidates. The accuracy of
Condorcet systems drops to 99.43%... and the accuracy of IRV to 56.92%
(these figures from 100k trials).
To be quite clear: I am not saying that Tideman's evaluations are wrong
because they contradict my own; I am saying that they are wrong because
they contradict the Median Voter Theorem; that my own evaluation
attaches numerical figures to an otherwise qualitative argument; and
that the Tideman results are also difficult to reconcile with those in
other published evaluations (Chamberlin and Cohen (1978) and Darlington).
Incidentally there was also a much earlier evaluation by Samuel Merrill
III. He defined utility as 'decreasing linearly with (Euclidean)
distance' (p26) which brings him under the purview of the Median Voter
Theorem, but he nonetheless found the Borda count to outperform
Condorcet methods. In his own words (p24) "we will see that this
criterion [ie. of maximising utility] and the Condorcet criterion need
not agree". I don't trust Merrill's evaluation either, and in this I
have some powerful support from Warren D. Smith, who wrote ("Range
voting", p24) "That suggests that Merrill's computer program had bugs".
CJC.
Colin, I hope you read my paper.
https://drive.google.com/file/d/1jIhFQfEoxSdyRz5SqEjZotbVDx4xshwM/view
--
r b-j . _ . _ . _ . _ rbj@audioimagination.com
"Imagination is more important than knowledge."
.
.
.
*To All, *
As John Stuart Mill said, in Representative Government, majority rule is
not democracy but maiorocracy. Maiorocracy is minimal democracy. It is
single majority rule, of over half the votes. It’s logical extension, in
the Droop quota, is multi-majority rule. Proportional representation is
the generalisation of single majority rule.
That is, if as much attention is paid to the representation part of PR.
That requires a preference vote, of personal order of choice, or ranked
choice.
To talk about Hare ranked choice vote or Hare IRV is inaccurate and
misleading. The Hare system is immutably the proportional count of an
ordinal vote, in large constituencies.
The HG Wells formula, which followed Hare and Mill, is proportional
representation with the single transferable vote in a large constituencies.
Yours sincerely,
Richard Lung.
On 14/11/2021 09:46, robert bristow-johnson wrote:
Colin, I hope you read my paper.
https://drive.google.com/file/d/1jIhFQfEoxSdyRz5SqEjZotbVDx4xshwM/view
--
r b-j . _ . _ . _ . _rbj@audioimagination.com
"Imagination is more important than knowledge."
.
.
.
Election-Methods mailing list - seehttps://electorama.com/em for list info
Hi Robert,
Thank you for highlighting your paper. More below:
On Sun, Nov 14, 2021 at 1:46 AM robert bristow-johnson
rbj@audioimagination.com wrote:
Colin, I hope you read my paper.
https://drive.google.com/file/d/1jIhFQfEoxSdyRz5SqEjZotbVDx4xshwM/view
I've taken a closer look at your paper, after taking a look at the
Tideman paper that I believe that Colin was referring to. I
appreciate that you have not mischaracterized your paper, and that
your paper is very salient to this conversation, and that you provided
a link to it.
I'm much more positive about the recent developments in Fargo than you
seem to be (as implied by the opening statements of your paper).
However, I believe that Ka-Ping Yee's simulations demonstrate a very
important characteristic about approval voting. Here's a link to
Yee's work again:
http://zesty.ca/voting/sim/
Yee's work appears to show that approval voting results are MUCH more
likely to align with Condorcet-winner-compliant methods than
Hare/IRV/RCV elections. This is a big reason why I'm pretty sanguine
(and even a bit enthusiastic) about the implementation of approval in
Fargo and St Louis. Do we differ on this point?
Burlington's 2009 election was arguably an anomaly, which you point
out in your paper. I appreciate that Hare/IRV/RCV elections choose
the Condorcet winner the vast majority of the time. I also appreciate
that bridges that I drive over have routinely "done their job" and
didn't collapse beneath my vehicle. I appreciate that almost all of
the flights that I've been on have been routine affairs, and that the
ones that weren't still resulted in my safe arrival at my destination.
We know that bridge collapses and airplane wrecks are very anomalous
events. We don't know if Hare/IRV/RCV's failures are a 1 in 100 type
of event, or 1 in 1000, or even more rare. I'm grateful that EVERY
commercial airliner crash receives thorough scrutiny, and I appreciate
your perspective on the 2009 election in Burlington, since my
understanding is that you participated in that election.
Prior to Burlington 2009, the IRV<->Condorcet discrepancy that I liked
to study was the Debian Project Leader election in 2003. I should
probably provide a more accessible writeup than this one:
https://electowiki.org/wiki/User:RobLa/Debian2003
It's not only a clinical evaluation of the end result that bothers me
about IRV elections. It's also about the candidate and voter behavior
that is elicited prior to the election. Because IRV is subject to
"center squeeze" (as you point out in your paper), candidates are
motivated to appeal to extreme factions of their electoral base.
Centrism (and compromise) becomes vilified by activists. Do I have
mathematical proof of this? No, of course not. This paragraph is a
political analysis, not a scientific analysis -- but I'm pretty
confident in my punditry on this subject.
Regardless, thanks for providing a link to your paper. I think this
mailing list becomes a more valuable resource with relevant links.
You would have received extra bonus points (in my mind) by providing a
quick summary of the paper (or rather, the "tl;dr version", as the
kids like to call it, or an "abstract" as academics like to call it).
However, by keeping your message brief, you avoided inscrutable jargon
and you avoided posting a misinterpretation of your paper. Kudos for
that!
Rob
On 11/14/21 10:38 AM, Colin Champion wrote:
Forrest wrote: "If people interested in voting methods reform would take
the time to digest these basic facts .... they would never accept any
'ranked choice voting' method unless it satisfied the Condorcet
Criterion." I think that a defence can be offered for people who reject
the Condorcet principle.
Firstly, some published evaluations show no appreciable difference in
performance between Condorcet methods and IRV. In Tideman and
Plassmann's 2012 paper, Table 1 appears to show that when the number of
voters is large, Condorcet methods are 94.46% accurate and AV/IRV is
94.41% accurate. A twentieth of a percent difference! In Table 2 of
Green-Armytage et al (2015) you get similar numbers: Minimax is 95.19%
accurate and "Hare" 94.45%. If the difference really is that small, then
IRV has the advantage of known resistance to tactical voting and has the
benefit of having been widely used in practice. There should be no
argument that IRV is the way to go.
In my view there are two weaknesses with this argument. I think (i) that
having 3 candidates in a multidimensional space makes the problem
unrealistically easy, and (ii) - notwithstanding (i) - that these
results could only have been produced by buggy software. I'll say more
about this later. But Tideman is probably the most respected worker in
the field. You can't argue against IRV if you don't admit that his
evaluations have been seriously misleading.
Secondly, it seems to me that supporters of IRV generally acknowledge
the defects of their method (while probably not being aware of their
magnitude). They consider that at least IRV has a realistic chance of
adoption. They point to the fact that their critics are divided into
1000 factions, that they attach too much importance to theological
arguments about logical criteria, and that they often end up advocating
unrealistic methods. This allows Condorcet supporters to be portrayed as
lacking social responsibilty: see
https://rangevoting.org/SchulzeComplic.html.
There are two responses to that, I think.
First (as a proponent of binary criteria) I would make the argument that
the dynamics can shift the method into a vulnerable area, and that thus,
failure can become much more severe than what it looks like by a simple
simulation. Another way to argue this point is to say that we don't know
the voting distribution, so any statistics gathered about "how often" a
method fails will be imprecise at best.
For instance, IRV has center squeeze failure with three or more viable
candidates - the Burlington problem. If IRV is intended to be used in a
party with only two viable candidates (to make sure that no-hopes can't
swing the election), then all well and good. But if the point is to
support multiple parties, then this center squeeze will be a serious
obstactle to doing so.
If, in the voter distribution that one samples over, three viable
candidtes is rare, then the problem won't appear on those tests. (So
it's better to something like Impartial Culture where almost every
election is an epsilon away from a perfect tie in the limit of many
voters; or an explicit spatial model that takes multiple viable
candidates directly into account.)
Of course, if you want two party rule, then this is a feature, not a
bug. See e.g. David L. Wetzell's posts from 2011 and 2012.
The second response is much simpler. It's better to vote for what you
want and not get it, than vote for what you don't want and get it.
There's something of an irony that the momentum argument uses the logic
of the method its proponents want to replace: "choose IRV because it's
got the following right now". I.e. vote for the lesser evil. And the
implication isn't even true! In the US, other states are experimenting
with other methods. Granted, they're usually cardinal ones (Approval or
Approval-runoff), but it shows that one doesn't have to vote for IRV to
get results.
I would imagine that the reason that there's no Condorcet in the US is
because there's no unified advocacy organization around an advanced
Condorcet method like Ranked Pairs. The closest the US got was Toby
Nixon's campaign for using Schulze in Washington state:
https://en.wikipedia.org/wiki/Electoral_reform_in_Washington_(state),
which failed. There's also Marquette's use of Nanson:
https://en.wikipedia.org/wiki/Nanson%27s_method#Use_of_Nanson_and_Baldwin,
but I don't think they specifically chose this method for its Condorcet
compliance.
On a side note, when Warren says that any method "significantly more
complicated than range" is just "mental masturbation", I think that he
proves too much, because IRV is such a method.
Finally, voting methods are generally part of larger electoral systems,
and decisiveness is often as important as fairness. In the UK, electoral
reformers start off thinking they have irresistable logical arguments,
and end up getting bogged down in unwinnable debates about the need for
'firm government'. (I can say nothing about the USA, whose institutions
I don't understand.) Unless you can argue that a change of voting method
will not do more harm through indecisiveness than it does good through
fairness, you haven't really got an argument in favour of Condorcet
methods.
There's a sort of duality here. On the one hand, the reason to want to
replace Plurality with something else is to change the dynamics of the
system from what Plurality produces to something (considered by the
reformers to be) better. From that position, you wouldn't expect
particular features of Plurality SMD to carry over to say, Condorcet
SMD. On the other, too much of a change may feel too risky, and I guess
that's where the concern for firm government comes from.
So to this I would respond, again, with two points:
I would expect that single-member Condorcet would produce less
fragmentation than PR, because parties who enjoy minority support
everywhere but majority nearly nowhere would still not be elected.
Second, complete proportional representation is not that bad, either, if
managed properly; and doesn't have to lead to gridlock.
The country where I live (Norway) has a particularly strong legislature
and weak executive: there are no snap elections, minority or coalition
governments are the norm, and the way the bill submission process works
makes it unlikely for the executive to propose bills it knows won't have
support by a majority of the legislature. Still, there's no paralysis:
the governmental process works fine.
As I tend to say, the major difference between PR and two-party is that
in PR countries, the voters show their support for the factions and then
these factions negotiate. In two-party systems, the factions negotiate
(within their respective parties), and then the voters show their
support. There's no reason the latter should inherently be better than
the former. Even two-party democracies can get paralyzed if one of the
parties decides no longer to play by the rules.
=====
On evaluations. The Median Voter Theorem (which I think Forrest was
alluding to) predicts that if a large number of voters come from a
symmetric distribution (eg Gaussian), then all Condorcet methods will
elect the candidate closest to the point in space which minimises the
sum of distances to voters (ie. the centre of the distribution). This is
not quite the same as electing the candidate who minimises the sum of
distances to voters, who will be identified as the rightful winner under
standard evaluation procedures. But the difference is tiny, and cannot
account for the 5% error rate attributed to Condorcet methods by Tideman
and his coworkers.
IIRC, the relevant theorem is a multidimensional extension of Black's
singlepeakedness theorem. See https://www.rangevoting.org/BlackSingle.html.
I described an evaluation of my own in a previous post. I used Gaussian
mixture models instead of pure Gaussians precisely in order to escape
from the Median Voter Theorem; otherwise the Condorcet systems would
have been indistinguishable from each other. But it's a trivial change
to revert to a single Gaussian. When I do so, the accuracy of Condorcet
methods is 99.73% and that of IRV is 95.81% (3 candidates, 30001 voters,
a million trials). Similar to Tideman et al for IRV; totally different
for Condorcet.
Now see what happens when we go up to 9 candidates. The accuracy of
Condorcet systems drops to 99.43%... and the accuracy of IRV to 56.92%
(these figures from 100k trials).
This seems to agree with Brian Olson's results that IRV gets
comparatively worse the more candidates you add. See
https://bolson.org/voting/twographs.html.
To be quite clear: I am not saying that Tideman's evaluations are wrong
because they contradict my own; I am saying that they are wrong because
they contradict the Median Voter Theorem; that my own evaluation
attaches numerical figures to an otherwise qualitative argument; and
that the Tideman results are also difficult to reconcile with those in
other published evaluations (Chamberlin and Cohen (1978) and Darlington).
Incidentally there was also a much earlier evaluation by Samuel Merrill
III. He defined utility as 'decreasing linearly with (Euclidean)
distance' (p26) which brings him under the purview of the Median Voter
Theorem, but he nonetheless found the Borda count to outperform
Condorcet methods. In his own words (p24) "we will see that this
criterion [ie. of maximising utility] and the Condorcet criterion need
not agree". I don't trust Merrill's evaluation either, and in this I
have some powerful support from Warren D. Smith, who wrote ("Range
voting", p24) "That suggests that Merrill's computer program had bugs".
Even though Merrill might be wrong, center-biased methods like Borda and
Sinkhorn seem to produce better VSE/Bayesian Regret results than
"neutral" methods. The only full IEVS run I could find published on the
rangevoting site is this one with a 50-50 mix of strategy and honest:
https://rangevoting.org/StratHonMix.html. Here, center-biased Borda and
Sinkhorn both do better than neutral Condorcet
The problem with these methods is that they're not fair, and that, since
this is a ranked ballot setting, their center bias is exploitable. Borda
is very vulnerable to teaming - presumably Sinkhorn would also be so.
I've done some calculations on the proportion of elections where the
most strategy-resistant method fails to strategy, for few candidates and
voters. It would be interesting to trace the Pareto front for Bayesian
Regret and manipulability. One more task to add to my queue! I have much
too little time to do everything I want to do.
-km
Second, complete proportional representation is not that bad, either, if
managed properly; and doesn't have to lead to gridlock.
(...)
As I tend to say, the major difference between PR and two-party is that
in PR countries, the voters show their support for the factions and then
these factions negotiate. In two-party systems, the factions negotiate
(within their respective parties), and then the voters show their
support. There's no reason the latter should inherently be better than
the former. Even two-party democracies can get paralyzed if one of the
parties decides no longer to play by the rules.
As an aside since the debate has broadened considerably anyway:
To me, a Central European, it is still quite strange how little the
American debate on electoral reform focuses on the option of multimember
constituencies (the reform of House elections from single-member
districts to a per-state PR method perhaps being the most obvious
candidate).
The main argument I find for the "first show support, then negotiate"
paradigm is that it gives the votes more expressive power
AND makes the negotiation process more transparent and observable
for the general public.
Jan
On Mon, Nov 15, 2021 at 1:00 AM Kristofer Munsterhjelm km_elmet@t-online.de
wrote:
On 11/14/21 10:38 AM, Colin Champion wrote:
Forrest wrote: "If people interested in voting methods reform would take
the time to digest these basic facts .... they would never accept any
'ranked choice voting' method unless it satisfied the Condorcet
Criterion." I think that a defence can be offered for people who reject
the Condorcet principle.
Firstly, some published evaluations show no appreciable difference in
performance between Condorcet methods and IRV. In Tideman and
Plassmann's 2012 paper, Table 1 appears to show that when the number of
voters is large, Condorcet methods are 94.46% accurate and AV/IRV is
94.41% accurate. A twentieth of a percent difference! In Table 2 of
Green-Armytage et al (2015) you get similar numbers: Minimax is 95.19%
accurate and "Hare" 94.45%. If the difference really is that small, then
IRV has the advantage of known resistance to tactical voting and has the
benefit of having been widely used in practice. There should be no
argument that IRV is the way to go.
In my view there are two weaknesses with this argument. I think (i) that
having 3 candidates in a multidimensional space makes the problem
unrealistically easy, and (ii) - notwithstanding (i) - that these
results could only have been produced by buggy software. I'll say more
about this later. But Tideman is probably the most respected worker in
the field. You can't argue against IRV if you don't admit that his
evaluations have been seriously misleading.
Secondly, it seems to me that supporters of IRV generally acknowledge
the defects of their method (while probably not being aware of their
magnitude). They consider that at least IRV has a realistic chance of
adoption. They point to the fact that their critics are divided into
1000 factions, that they attach too much importance to theological
arguments about logical criteria, and that they often end up advocating
unrealistic methods. This allows Condorcet supporters to be portrayed as
lacking social responsibilty: see
https://rangevoting.org/SchulzeComplic.html.
There are two responses to that, I think.
First (as a proponent of binary criteria) I would make the argument that
the dynamics can shift the method into a vulnerable area, and that thus,
failure can become much more severe than what it looks like by a simple
simulation. Another way to argue this point is to say that we don't know
the voting distribution, so any statistics gathered about "how often" a
method fails will be imprecise at best.
For instance, IRV has center squeeze failure with three or more viable
candidates - the Burlington problem. If IRV is intended to be used in a
party with only two viable candidates (to make sure that no-hopes can't
swing the election), then all well and good. But if the point is to
support multiple parties, then this center squeeze will be a serious
obstactle to doing so.
If, in the voter distribution that one samples over, three viable
candidtes is rare, then the problem won't appear on those tests. (So
it's better to something like Impartial Culture where almost every
election is an epsilon away from a perfect tie in the limit of many
voters; or an explicit spatial model that takes multiple viable
candidates directly into account.)
Of course, if you want two party rule, then this is a feature, not a
bug. See e.g. David L. Wetzell's posts from 2011 and 2012.
The second response is much simpler. It's better to vote for what you
want and not get it, than vote for what you don't want and get it.
There's something of an irony that the momentum argument uses the logic
of the method its proponents want to replace: "choose IRV because it's
got the following right now". I.e. vote for the lesser evil. And the
implication isn't even true! In the US, other states are experimenting
with other methods. Granted, they're usually cardinal ones (Approval or
Approval-runoff), but it shows that one doesn't have to vote for IRV to
get results.
I would imagine that the reason that there's no Condorcet in the US is
because there's no unified advocacy organization around an advanced
Condorcet method like Ranked Pairs. The closest the US got was Toby
Nixon's campaign for using Schulze in Washington state:
https://en.wikipedia.org/wiki/Electoral_reform_in_Washington_(state),
which failed. There's also Marquette's use of Nanson:
https://en.wikipedia.org/wiki/Nanson%27s_method#Use_of_Nanson_and_Baldwin,
but I don't think they specifically chose this method for its Condorcet
compliance.
On a side note, when Warren says that any method "significantly more
complicated than range" is just "mental masturbation", I think that he
proves too much, because IRV is such a method.
Finally, voting methods are generally part of larger electoral systems,
and decisiveness is often as important as fairness. In the UK, electoral
reformers start off thinking they have irresistable logical arguments,
and end up getting bogged down in unwinnable debates about the need for
'firm government'. (I can say nothing about the USA, whose institutions
I don't understand.) Unless you can argue that a change of voting method
will not do more harm through indecisiveness than it does good through
fairness, you haven't really got an argument in favour of Condorcet
methods.
There's a sort of duality here. On the one hand, the reason to want to
replace Plurality with something else is to change the dynamics of the
system from what Plurality produces to something (considered by the
reformers to be) better. From that position, you wouldn't expect
particular features of Plurality SMD to carry over to say, Condorcet
SMD. On the other, too much of a change may feel too risky, and I guess
that's where the concern for firm government comes from.
So to this I would respond, again, with two points:
I would expect that single-member Condorcet would produce less
fragmentation than PR, because parties who enjoy minority support
everywhere but majority nearly nowhere would still not be elected.
Second, complete proportional representation is not that bad, either, if
managed properly; and doesn't have to lead to gridlock.
The country where I live (Norway) has a particularly strong legislature
and weak executive: there are no snap elections, minority or coalition
governments are the norm, and the way the bill submission process works
makes it unlikely for the executive to propose bills it knows won't have
support by a majority of the legislature. Still, there's no paralysis:
the governmental process works fine.
As I tend to say, the major difference between PR and two-party is that
in PR countries, the voters show their support for the factions and then
these factions negotiate. In two-party systems, the factions negotiate
(within their respective parties), and then the voters show their
support. There's no reason the latter should inherently be better than
the former. Even two-party democracies can get paralyzed if one of the
parties decides no longer to play by the rules.
=====
On evaluations. The Median Voter Theorem (which I think Forrest was
alluding to) predicts that if a large number of voters come from a
symmetric distribution (eg Gaussian), then all Condorcet methods will
elect the candidate closest to the point in space which minimises the
sum of distances to voters (ie. the centre of the distribution). This is
not quite the same as electing the candidate who minimises the sum of
distances to voters, who will be identified as the rightful winner under
standard evaluation procedures. But the difference is tiny, and cannot
account for the 5% error rate attributed to Condorcet methods by Tideman
and his coworkers.
IIRC, the relevant theorem is a multidimensional extension of Black's
singlepeakedness theorem. See https://www.rangevoting.org/BlackSingle.html
.
I described an evaluation of my own in a previous post. I used Gaussian
mixture models instead of pure Gaussians precisely in order to escape
from the Median Voter Theorem; otherwise the Condorcet systems would
have been indistinguishable from each other. But it's a trivial change
to revert to a single Gaussian. When I do so, the accuracy of Condorcet
methods is 99.73% and that of IRV is 95.81% (3 candidates, 30001 voters,
a million trials). Similar to Tideman et al for IRV; totally different
for Condorcet.
Now see what happens when we go up to 9 candidates. The accuracy of
Condorcet systems drops to 99.43%... and the accuracy of IRV to 56.92%
(these figures from 100k trials).
This seems to agree with Brian Olson's results that IRV gets
comparatively worse the more candidates you add. See
https://bolson.org/voting/twographs.html.
To be quite clear: I am not saying that Tideman's evaluations are wrong
because they contradict my own; I am saying that they are wrong because
they contradict the Median Voter Theorem; that my own evaluation
attaches numerical figures to an otherwise qualitative argument; and
that the Tideman results are also difficult to reconcile with those in
other published evaluations (Chamberlin and Cohen (1978) and Darlington).
Incidentally there was also a much earlier evaluation by Samuel Merrill
III. He defined utility as 'decreasing linearly with (Euclidean)
distance' (p26) which brings him under the purview of the Median Voter
Theorem, but he nonetheless found the Borda count to outperform
Condorcet methods. In his own words (p24) "we will see that this
criterion [ie. of maximising utility] and the Condorcet criterion need
not agree". I don't trust Merrill's evaluation either, and in this I
have some powerful support from Warren D. Smith, who wrote ("Range
voting", p24) "That suggests that Merrill's computer program had bugs".
Even though Merrill might be wrong, center-biased methods like Borda and
Sinkhorn seem to produce better VSE/Bayesian Regret results than
"neutral" methods. The only full IEVS run I could find published on the
rangevoting site is this one with a 50-50 mix of strategy and honest:
https://rangevoting.org/StratHonMix.html. Here, center-biased Borda and
Sinkhorn both do better than neutral Condorcet
The problem with these methods is that they're not fair, and that, since
this is a ranked ballot setting, their center bias is exploitable. Borda
is very vulnerable to teaming - presumably Sinkhorn would also be so.
I've done some calculations on the proportion of elections where the
most strategy-resistant method fails to strategy, for few candidates and
voters. It would be interesting to trace the Pareto front for Bayesian
Regret and manipulability. One more task to add to my queue! I have much
too little time to do everything I want to do.
-km
Election-Methods mailing list - see https://electorama.com/em for list
info
On Mon, Nov 15, 2021 at 2:49 PM Jan Šimbera simbera.jan@gmail.com wrote:
As an aside since the debate has broadened considerably anyway:
To me, a Central European, it is still quite strange how little the
American debate on electoral reform focuses on the option of multimember
constituencies (the reform of House elections from single-member
districts to a per-state PR method perhaps being the most obvious
candidate).
The main argument I find for the "first show support, then negotiate"
paradigm is that it gives the votes more expressive power
AND makes the negotiation process more transparent and observable
for the general public.
Yeah. I think multimember precincts are a brilliant solution but my
impression is that anglo-saxon countries are really stuck on the idea of
single member districts (Ireland being a notable exception). The argument
I've heard is that the elected official is there to represent their
particular region, but I've never been persuaded by that argument. I've
lived in three anglo-saxon countries (Canada, UK, US) and national politics
are always national. I've never heard of an MP or member of congress
actually push for a little parochial issue that is specific to their
particular spot in the country. It all seems to be party-line votes
regardless. If politicians are going to behave that way, then we might as
well just have a system with proportional representation. I would love to
see STV in more places. I think in the US specifically there are
constitutional barriers to multi-member districts.
--
Dr. Daniel Carrera
Postdoctoral Research Associate
Iowa State University
I think in the US specifically there are constitutional barriers to
multi-member districts.
As far as I understand both the US Constitution and [1], the barrier is not
constitutional but on the level of a congressional act, making it much
easier to change. Please correct me if I'm wrong!
[1]: The Apportionment Act of 1842: “In All Cases, By District” | US House
of Representatives: History, Art & Archives
https://history.house.gov/Blog/2019/April/4-16-Apportionment-1/
On Mon, Nov 15, 2021 at 10:05 PM Daniel Carrera dcarrera@gmail.com wrote:
On Mon, Nov 15, 2021 at 2:49 PM Jan Šimbera simbera.jan@gmail.com wrote:
As an aside since the debate has broadened considerably anyway:
To me, a Central European, it is still quite strange how little the
American debate on electoral reform focuses on the option of multimember
constituencies (the reform of House elections from single-member
districts to a per-state PR method perhaps being the most obvious
candidate).
The main argument I find for the "first show support, then negotiate"
paradigm is that it gives the votes more expressive power
AND makes the negotiation process more transparent and observable
for the general public.
Yeah. I think multimember precincts are a brilliant solution but my
impression is that anglo-saxon countries are really stuck on the idea of
single member districts (Ireland being a notable exception). The argument
I've heard is that the elected official is there to represent their
particular region, but I've never been persuaded by that argument. I've
lived in three anglo-saxon countries (Canada, UK, US) and national politics
are always national. I've never heard of an MP or member of congress
actually push for a little parochial issue that is specific to their
particular spot in the country. It all seems to be party-line votes
regardless. If politicians are going to behave that way, then we might as
well just have a system with proportional representation. I would love to
see STV in more places. I think in the US specifically there are
constitutional barriers to multi-member districts.
--
Dr. Daniel Carrera
Postdoctoral Research Associate
Iowa State University
On 15.11.2021 22:04, Daniel Carrera wrote:
I've lived in three anglo-saxon countries (Canada, UK, US) and national
politics are always national. I've never heard of an MP or member of
congress actually push for a little parochial issue that is specific to
their particular spot in the country. It all seems to be party-line
votes regardless. If politicians are going to behave that way, then we
might as well just have a system with proportional representation. I
would love to see STV in more places.
I agree. It's not like the US is completely foreign to the concept - New
York used STV to temporarily break the political machine there (until it
struck back and got it repealed by red-baiting).
And I would prefer STV (with single-ticket MMP if that's not too
complex) to party list because STV also allows the voters to express
preferences for factions within a party while these factions are too
small to form parties of their own.
The downside of STV compared to party list is that the relatively small
district sizes reduce party proportionality, which is why it ideally
should have an MMP component (and ideally, the list ticket should be
constructed from the voters' preferences like Schulze's MMP proposal
does). But that might be a little too much to ask for in one go.
-km
By the way, I have studied the subject of election method, for over half a century, and written over half a dozen free Smashwords books on scientific method of elections etc.
Most recently, I published two short booklets or pamphlets on "Binomial STV". This looks like an ordinary preference vote or ranked choice ballot. The difference is that the preferences both elect and exclude. So, the voters now have as much power to exclude candidates, as well as elect candidates. Hence, the term bi-nomial STV.
Suppose 10 candidates for 5 seats. With a binomial count, your preference 10 counts as much to exclude a candidate, as preference 1 counts to elect a candidate. Preference 9 is as excluding, as preference 2 is electing, and so on. But you don't have to name all the preferences. Naming none of the preferences is like NOTA (none of the above).
No electoral system in the world offers this. They are all elections, plus arbitrary rules or ad hoc ways of excluding candidates, over which the public has little control. This is as true of STV as all the other systems -- until now.
Originally, I devised a whole logical structure called FAB STV: Four Averages Binomial Single Transferable Vote. (I wrote a full length book about it.) Recently, I have developed hand count versions. My hand count versions do not transgress traditionally acceptable and unnoticable short-falls in STV accuracy, over the last century. But they are simpler, at least in conception. And they are much more powerful voting tools for the public.
I ask your organisations to try them in pilot schemes. Ask me about the working. Send me your Binomial STV hand count of a Binomial STV election.
Profile page
https://www.smashwords.com/profile/view/democracyscience
Elect and Exclude.
https://www.smashwords.com/books/view/1111349
Super-vote
https://www.smashwords.com/books/view/1106292
Regards,
Richard Lung.
On 15 Nov 2021, at 9:28 pm, Jan Šimbera simbera.jan@gmail.com wrote:
I think in the US specifically there are constitutional barriers to multi-member districts.
As far as I understand both the US Constitution and [1], the barrier is not constitutional but on the level of a congressional act, making it much easier to change. Please correct me if I'm wrong!
[1]: The Apportionment Act of 1842: “In All Cases, By District” | US House of Representatives: History, Art & Archives
On Mon, Nov 15, 2021 at 10:05 PM Daniel Carrera dcarrera@gmail.com wrote:
On Mon, Nov 15, 2021 at 2:49 PM Jan Šimbera simbera.jan@gmail.com wrote:
As an aside since the debate has broadened considerably anyway:
To me, a Central European, it is still quite strange how little the
American debate on electoral reform focuses on the option of multimember
constituencies (the reform of House elections from single-member
districts to a per-state PR method perhaps being the most obvious candidate).
The main argument I find for the "first show support, then negotiate"
paradigm is that it gives the votes more expressive power
AND makes the negotiation process more transparent and observable
for the general public.
Yeah. I think multimember precincts are a brilliant solution but my impression is that anglo-saxon countries are really stuck on the idea of single member districts (Ireland being a notable exception). The argument I've heard is that the elected official is there to represent their particular region, but I've never been persuaded by that argument. I've lived in three anglo-saxon countries (Canada, UK, US) and national politics are always national. I've never heard of an MP or member of congress actually push for a little parochial issue that is specific to their particular spot in the country. It all seems to be party-line votes regardless. If politicians are going to behave that way, then we might as well just have a system with proportional representation. I would love to see STV in more places. I think in the US specifically there are constitutional barriers to multi-member districts.
--
Dr. Daniel Carrera
Postdoctoral Research Associate
Iowa State University
Election-Methods mailing list - see https://electorama.com/em for list info