Re: [EM] 19) APR: Steve's 19th dialogue with Richard Fobes
On 6/30/2015 7:39 PM, steve bosworth wrote:
...
S: I accept that your method might mathematically at most provide
'nearly full proportionality'. However, APR offers the advantage of
'full proportionality'. Do you dispute this?
Yes I dispute this. As I have said before (and I think someone else
made a similar point), your APR method does not achieve full
proportionality. Specifically, with APR, not every voter is represented
by hisher first choice.
No method can achieve 100% percent proportionality. If you want to say
that APR gets as close as is easily possible, then I'll agree with that
on the condition that you also acknowledge that VoteFair ranking also
can (if desired) achieve that same high level of proportionality.
... APR also removes even the
small degree of gerrymandering that may continue with regard to the
establishment, for example, of any of your smaller than 'state wide
seats' for electing California's Legislative Assembly. Do you agree?
No I do not agree.
I do agree that your APR method cannot be gerrymandered. But that
advantage occurs at the loss of demographic proportionality.
I don't understand what you are specifically saying above in the part of
your sentence that says:
... for example, of any of your smaller than 'state wide
seats' for electing California's Legislative Assembly.
Regarding:
S: Perhaps you did not notice that Section A of each 'association's'
ballot would only list the candidates seeking to represent that
association.
If plurality is replaced, lots and lots of citizens will want to jump
into politics to fix what's wrong. I don't see where the initial number
of candidates will be anything but large.
R: Remember that debates between dozens of candidates become
impractical.
S: As with every electoral system, candidates will debate with
whichever other candidates they choose. APR has the advantage of
prompting citizens to observe, study, and rank as few or as many of all
the candidates running in the state or nation as they wish.
You seem to say, on the one hand, that APR imposes no limits on the
number of candidates, yet on the other hand you say that comparing those
many candidates will not be a problem.
How do you envision voters finding the time to compare even more
candidates than currently? Getting specific, the U.S. presidential
election currently has more than 20 candidates. In APR there is only
one chance to rank candidates (because there is nothing like a primary
election), so how do people choose which candidates to focus on learning
more about in order to rank them?
I'll argue that VoteFair ranking greatly reduces the effectiveness of
campaign contributions compared to most other election methods.
S: You have frequently asserted this but I have not yet seen that
you have 'argued' for this yet, especially in preference to APR.
What? In multiple messages I have described multiple ways in which APR
is vulnerable to manipulation through the use of money.
In addition, "Ending The Hidden Unfairness In U.S. Elections" explains
in detail how money is currently used to influence election results, and
your APR method is vulnerable to some of the same tactics, plus APR is
vulnerable to new tactics that I have previously explained in earlier
messages to you.
S: Equally, I do not yet see that you have addressed my following
claims in our 18^th dialogue:
Aside from these important relative weaknesses of VoteFair when
compared
to APR for electing an assembly, I see VoteFair's greater
mathematical
complexity, its remaining arbitrariness in determining its electoral
districts, and its still wasting some votes (for example by its
offering
a more limited choice of candidates for electors) as seeming to
make it
less likely (and less worthy than APR) to replace the existing
system in
California. More Californians would understand APR.
Repeating myself, yes more voters/citizens would understand APR's
counting method.
Yet from a voter's perspective, marking ballots would be much simpler
using VoteFair ranking. Only the calculations done on a computer are
"complex" in terms of VoteFair ranking not being simple to understand.
In contrast, figuring out how to mark an APR ballot is complex. It is
APR's counting method that is simpler.
Why do you regard "remaining arbitrariness in determining its electoral
districts" as a disadvantage? The best defense against gerrymandering
is to ensure that gerrymandering is not possible.
As for "[limiting the] choice of candidates for electors," the
voters/electors are the ones who do that limiting in the primary
election. (In the primary election, VoteFair ranking does not need to
impose any limit on the number of candidates.)
As for worthiness for use in California, you are the person who is
promoting APR for use there. VoteFair ranking would be a better choice.
Yet the reality is that election reform in California is a very long
way into the future.
If I have missed answering any of your latest questions, please note
that your non-standard way of marking your most recent
comments/questions is difficult to follow (as someone else has also
pointed out).
As you may have noticed, I haven't had lots of time lately. (I'm
writing this in haste.) Yet if you do have specific questions, and they
are not repeats of questions I've already answered, please do ask.
Thank you for taking the time to better understand election-method
complexities.
Richard Fobes
On 6/30/2015 7:39 PM, steve bosworth wrote:
(19) APR: Steve's 19th dialogue with Richard Fobes
Date: Thu, 25 Jun 2015 15:21:19 -0700
From: ElectionMethods@VoteFair.org
To: election-methods@lists.electorama.com
CC: stevebosworth@hotmail.com
Subject: Re: (18) APR: Steve's 18th dialogue with Richard Fobes
On 6/15/2015 1:56 PM, steve bosworth wrote:
Yes, as a result of reading your book ("Ending The Hidden
Unfairness…”),
I think I do understand how both VoteFair popularity and representation
rankings could work. [...]
However, I still see it as offering less proportionality and
representativeness than APR for electing a legislative assembly. In
fact, you seem to acknowledge this APR advantage below:
You explicitly say that you do not “dispute” the fact that “these
VoteFair-based linkages between a specific ballot and a specific
representative are not as obvious as … in your APR method”.
“I do not dispute your claim that your APR method has the advantage
that
a voter can directly associate their vote with a particular elected
representative's voting influence. …
R: My comments about your APR method being relatively easy to use, and
relatively easy to understand, have nothing to do with degree of
proportionality.
You don't mention VoteFair partial proportional ranking, so please read
or reread, the chapter titled "It's Party Time!" (in my book "Ending the
Hidden Unfairness in U.S. Elections"). And note that this method can
implement nearly full proportional ranking simply by increasing the
number of "statewide seats."
S: I accept that your method might mathematically at most provide
'nearly full proportionality'. However, APR offers the advantage of
'full proportionality'. Do you dispute this? APR also removes even the
small degree of gerrymandering that may continue with regard to the
establishment, for example, of any of your smaller than 'state wide
seats' for electing California's Legislative Assembly. Do you agree?
... I see VoteFair's ... remaining arbitrariness in determining its
electoral districts ...
R: The best election methods cannot be gerrymandered, which means that
district boundaries can be adjusted in nearly any way
S: This is one of the reasons I see APR as offering the 'best
method'. It removes all the anti-democratic influence of gerrymandered
boundaries, as well as any districts that have produced safe-seats by
chance.
[….]
S: ... still wasting some votes (for example by its offering
a more limited choice of candidates for electors)
R: This is the flip side of your method's disadvantage that a ballot
would
list too many candidates.
S: Perhaps you did not notice that Section A of each 'association's'
ballot would only list the candidates seeking to represent that association.
R: Remember that debates between dozens of candidates become impractical.
S: As with every electoral system, candidates will debate with
whichever other candidates they choose. APR has the advantage of
prompting citizens to observe, study, and rank as few or as many of all
the candidates running in the state or nation as they wish.
S: However, against this APR advantage you again claim that it is more
vulnerable to money corruption. Several times before you have suggested
that APR would be more vulnerable in this regard but I still have not
seen your exact reasons for believing this. Please try again to specify
the nature of the extra vulnerability you see APR having in this
regard.
R: Once again you claim that you do not understand how your APR
method is
vulnerable to strategies that involve money. Rather than repeating the
reasons I've already explained, I'll explain yet another reason for its
vulnerability.
You seem to be assuming that an interest group can shift from [being] a
nonpolitical organization to a political organization without
corruption. The reality is that the moment an organization gains
significant influence in politics, (outside) money is used to pay
(inside) individuals to shift their opinions in ways that the financial
contributors desire.
As a simple example in the United States, the organization named the
Sierra Club became so popular that it begin to have an influence on
politics. As a result, money was used to entice top leaders to support
positions that were not consistent with environmental protection, which
was a core priority for most Sierra Club members.
I suspect that Green parties in Europe have experienced something
similar, namely a shift in priorities as a result of monetary influence.
The point is that an organization that was previously trusted becomes at
least partially corrupt when enough money is supplied to influence key
members in the organization. Note that money will be supplied in
proportion to the organization's influence on politics -- or more
specifically in proportion to the effectiveness of those contributions.
I'll argue that VoteFair ranking greatly reduces the effectiveness of
campaign contributions compared to most other election methods.
S: You have frequently asserted this but I have not yet seen that
you have 'argued' for this yet, especially in preference to APR. Of
course, I believe that every system (including APR) is somewhat
vulnerable to the corruptions you mention. But you seem not yet to have
explained why you think APR in more vulnerable than is your VoteFair
ranking proposal. In this connection, neither have you as yet also
explained why you doubt the validity of my explanation of how APR should
be less vulnerable for the reasons given at the end of my contribution
to 18^th dialogue, the contribution that ended with the following paragraph:
APR’s primary elections and associations should also help to reduce the
sometimes anti-democratic power of great wealth, celebrity, and the
mass
media. I see this as likely given the extent to which APR’s
‘associations’ would emerge from previously existing voluntary
organizations in society. These associations could benefit from the
loyalties among the population such organizations had enjoyed prior to
them being recognized as 'associations'. Presumably, many of these
organizations would already have some communication and mobilization
resources that are entirely independent of celebrity, the richest
sections of society, and the mass media. Thus, the adoption of APR
would
probably help to reduce the relative power of these sometimes
anti-democratic forces in determining how people and their
representatives vote. APR’s official political recognition of these
voluntary organizations would seem to assist many citizens more firmly,
securely, and independently to see that their own abiding interests are
best promoted and protected through the associational and
representational connections validated by APR.
S: Equally, I do not yet see that you have addressed my following
claims in our 18^th dialogue:
Aside from these important relative weaknesses of VoteFair when compared
to APR for electing an assembly, I see VoteFair's greater mathematical
complexity, its remaining arbitrariness in determining its electoral
districts, and its still wasting some votes (for example by its
offering
a more limited choice of candidates for electors) as seeming to make it
less likely (and less worthy than APR) to replace the existing
system in
California. More Californians would understand APR.
R: I think these are the main answers to your latest questions.
If you should want further details about how (the full system of)
VoteFair ranking achieves proportional results, please ask.
I continue to appreciate your progress in better understanding
election-method complexities.
Richard
On 07/12/2015 06:05 AM, Richard Fobes wrote:
On 6/30/2015 7:39 PM, steve bosworth wrote:
...
S: I accept that your method might mathematically at most provide
'nearly full proportionality'. However, APR offers the advantage of
'full proportionality'. Do you dispute this?
Yes I dispute this. As I have said before (and I think someone else
made a similar point), your APR method does not achieve full
proportionality. Specifically, with APR, not every voter is represented
by hisher first choice.
No method can achieve 100% percent proportionality. If you want to say
that APR gets as close as is easily possible, then I'll agree with that
on the condition that you also acknowledge that VoteFair ranking also
can (if desired) achieve that same high level of proportionality.
There's one aspect of this I was going to address in a reply of my own
to Steve, but I have been busy. Still, I can at least mention it here,
since it's relevant to what you're saying, and then I'll try to get that
reply done at some point.
Suppose all voters rank every candidate, and suppose you pick an
unpalatable set of candidates as winners. Then you can assign voters to
each of those winners: each voter is assigned to the winner that he
ranks first (of those in the winner set), like APR would do. (Call that
procedure "weighted assignment".) The candidates will have weights
proportional to their support among the winning set. But this hardly
seems like a good outcome, since the winning set only consists of
unpalatable candidates.
Concretely: If we have
40: A > B > C
60: D > E > F
then {AD} with 40% to A and 60% to D is better than {BE} with 40% to B
and 60% to E, even though in both cases, every voter's vote "counts" in
the sense of influencing a winner's weight.
Thus simply assigning every voter to the winner he prefers the most does
not in itself provide a good result if the method that picks the winners
to begin with is lacking. And IRV is not exactly the best of methods :)
One possible Condorcet approach could be:
Define the number of voters that are penalized when moving from one set
of winners (say {ABC}) to another (say {DEF}) as the number of voters
who prefer someone in the first set to someone in the second set (i.e.
ranks one of the former above one of the latter).
Say {ABC} beats {DEF} if fewer voters are penalized by going from {DEF}
to {ABC} than by going from {ABC} to {DEF}.
Let a penalty CW be the set that beats every other.
Multiwinner IRV most likely does not pick penalty CWs. Inasfar as
penalty CWs are good things, this is a mark against using multiwinner
IRV for picking the winner set -- even though every vote contributes to
adjusting weights no matter what winning set was picked, as long as
every voter ranks every candidate. And if we pick a penalty CW using a
Condorcet method, there's nothing stopping us from calculating weights
as above using that penalty CW set.
For that matter, you could use VoteFair proportional ranking to find a
winning set, and then use weighted assignment as a second stage if you
want weighted voting. Since weighted assignment works for any set that
doesn't contain candidates nobody ranks first among those in the set,
you can use the output from IRV, VoteFair PR, STV, Schulze STV, or
whatnot for the second stage. Some of these can be better than IRV-at
large: for instance, if I'm right about thresholds and that multiwinner
IRV gives each party a number of seats equal to its Droop quota support
in cloning equilibrium, then using STV would directly give that kind of
proportionality whereas multiwinner IRV would only do so when the
parties are all strategizing. Of course, if Droop proportionality is
undesirable, then using STV would be bad, but so would using IRV be.
Re: (4) APR: Steve's 4th dialogue with
Kristofer
From:
Subject:
Election-Methods Digest, Vol 133, Issue 2
To:
Date: Thu, 2 Jul 2015
12:01:24 -0700
…....................................................
Thresholded weighted multiwinner elections
(Kristofer
Munsterhjelm)
Date: Wed, 01 Jul 2015
22:14:11 +0200
From: Kristofer Munsterhjelm
To: Election Methods Mailing
Subject: [EM]
Thresholded weighted multiwinner elections
Message-ID:
Content-Type:
text/plain; charset=utf-8; format=flowed
Steve's
questions will follow each element of what Kristofer wrote:
K: I think I
see why the cloning attack is possible in two-stage weighted
voting. If I'm right, then it is possible to make voting methods that
produce results that fit weighted voting better -- at least
when the
voters are honest. However, I'm not sure if it is
possible at all if
enough voters are strategic.
S: Am I
mistaken in believing that, in practice, APR's 'weighted multiwinner
elections' would not be vulnerable to the threats either of effective
'cloning' or effective 'strategic voting'? This practical
invulnerability would seem to arise from the facts that APR's
election of reps to a large national assembly would allow all citizen
to rank as few or as many of all the thousands of candidates in the
country. Accordingly, for example, the portion of all the perceived
clones would be elected who were discover to be, for example, among
the 435 most popular candidates in the USA. Each elected candidate
would simply have a weighted vote in the assembly equal to the number
of votes that each had received directly or indirectly from citizens.
At the same time, how could any citizen or group of citizens be able
to have enough reliable knowledge about how enough other citizens
will rank candidates in order to be confident enough of having a
'strategy' that would have the effect of producing anything other
than an honest result? In any case, what rational motive would any
citizen or group of citizens have in ranking other than their favored
candidates when their honest voting would instead guarantee that each
of their votes will only strengthen the elected reps they favor more
than the other reps?
K: It might turn
out that the only way of
making weighted voting work is
through either varying the number of
winners (like in party
list) [...]
S: Is not this
what APR does, or have I misunderstood you here?.
K: [...] or by an
unconventional (nondeterministic) voting system or the Asset version
of this.
S: Is not this
what APR does, or have I misunderstood you here?>
K: First, why the
cloning attack is possible: when we use (call them semi-
majoritarian[1]) methods like IRV or Plurality,
if candidates represent parties who can clone as many as they
want, then I think the strategic equilibrium gives each party a
number of seats equal to their number of Droop quotas. If we instead
use an unweighted multiwinner method (STV,
Schulze STV,
etc), then the Droop proportionality criterion gives each
party at least their Droop quotas' worth in seats without strategy.
Simply, when the number of winners is fixed, the
semi-majoritarian
methods have an implicit threshold of a
Droop quota, and the unweighted
multiwinner methods have an
explicit threshold of the same.
S:
I understand that, above and below, you are exploring the logic of
these theoretical possibilities but why would we actually want to use
such needlessly less proportional and much more complicated methods
than those offered by APR for electing the legislative assembly of a
large nation?
Correct
me if I am mistaken, but perhaps your next post (also copied below)
provides part of your answer to this question. It seems to worry
that APR might elect a so-called 'unpalatable set' of reps for the
assembly. If this is part of your answer, do you still accept that
APR would always have the best chance of electing an assembly that
would be entirely palatable to its voting citizens. This is because
each citizen could rationally see that she has a rep in the assembly
who most likely will both qualitatively and mathematically
(proportionately) represent her views?
Is
your definition of 'unpalatable' something other than simply 'what
you happen subjectively to dislike?
For
more simplicity and clarity for our next dialogue, I think it would
be best for me to delay commenting on the relevant details of the
following parts of your 2 posts only after you have had a chance to
answer these questions.
I
look forward to your replies.
Steve
K: In that light, the cloning strategy in three-seat
26: A1 > A2 > B > C > D
26: A2 > A1 > C >
B > D
25: B > C > A1 > A2 > D
10: C >
B > A2 > A1 > D
5: D > A1 > A2 > B > C
works because the A-group has more than two Droop quotas (a Droop
quota
being 23 here).
Perhaps we'd want to
have no threshold at all, something like minimax
Approval
where we want to find the outcome that satisfies the voter who
likes it the least the most. But it'd seem unreasonable to elect {A1,
B,
C} in this extreme variant of the above:
1000: A1
A2 > B > C > D
1000: A2 > A1 > C > B >
D
500: B > C > A1 > A2 > D
2: C > B >
A2 > A1 > D
1: D > A1 > A2 > B > C
and hence, that implies there should be some kind of
threshold, but that
it should be lower than a Droop
quota[2]. A lower threshold would mean
that the assembly
would be more broad than deep: it would choose a
compromise
among popular candidates to make room for more specialized
candidates.
For instance, in a two-seat election
with an augmented LCR example like
50: L > C > R >
S
40: R > C > L > S
10: C > R > L >
S
20: S
the method could elect {LR} with a
high threshold, but instead elect
{CS} if the threshold were
lower. In return, the candidate C would have
a much greater
weight in the latter case than either L or R would have
in
the former.
The next thing to do would be to find a
proof of concept method that
would have a tunable threshold
just to show that it'x possible (at least
under honesty).
Here's one that reduces to Bucklin (if one picks a 50%
threshold):
==
Let X be a set of
winners and t a threshold (in number of voters). Then
evaluate(X, t) is a function that works on the ballots and returns a
list of numbers in sorted order from least to most.
evaluate(Y, t) is
"better" than evaluate(X, t) if
the first number where the output from
evaluate(Y, t)
differs from evaluate(X, t) is one where evaluate(Y, t)'s
number is greater than evaluate(X, t)'s. The best set is the one that
is
better than every other, and that set wins.
Evaluate itself just counts the ranks of the ballots (of the
candidates
in the set X), where first place is n, second
place is n-1, all the way
to nth place is 1 (and unranked is
0). It then sorts these and removes
the t worst.
==
Here's the two-seat LCR example above with a
Droop quota (40) and with a
threshold of 10. {LR} wins with
a Droop quota and {CS} with the
threshold of 10. To skip,
just search for #. I have omitted other sets
like CL, CR,
LS, etc.
evaluate({LR}, 40):
rank number: 4
3 2 1
50: *L C R S
40: *R C L S
10: C *R L
S
20: S
So we have 50 4s, 40 4s, 10 3s and
20 0s, or
20 0s, 10 3s, 90 4s
Threshold of 40 removes the 40 least, so the output is
80
4s.
evaluate({CS}, 40):
rank number: 4 3 2
1
50: L *C R S
40: R *C L S
10: *C R L S
20: *S
So we have 50 3s, 40 3s, 10 4s, 20 4s, or
90 3s, 30 4s
Threshold of 40 removes the 40
least, giving 50 3s and
30 4s.
So here {LR}
with 80 4s wins over {CS} with 50 3s and 30 4s.
With
a threshold of 10:
evaluate({LR}, 10):
As
above, before truncating, we have 20 0s, 10 3s, 90 4s
But now we can only remove 10 worst. So the final
output is
10 0s, 10 3s, 90 4s
evaluate({CS}, 10):
90
3s, 30 4s.
Removing 10 worst gives
80 3s, 30
4s.
So now {CS} with 80 3s and 30 4s wins over {LR}
with 10 0s
first, because 3 is clearly greater than 0.
Hence it's possible to make something
that has a tunable threshold under
honesty.
But here's a problem. In the single-seat case, this behaves like
Borda:
it may violate the majority criterion to elect a
candidate that has more
second-place votes. That is, in
something like
55: A>B>C
35: B>C>A
10: C>B>A
Borda will elect B, and with a threshold of
say, 10, so will the method
above:
evaluate({B}, 10)
gives (truncated) 55 2s, 35 3s
evaluate({A}, 10) gives
(truncated) 35 1s, 55 3s
evaluate({C}, 10) gives (truncated)
45 1s, 35 2s, 10 3s
All well and good. But for Borda, a
strategic majority can force a
winner by acting like an
unreasonable group or an aggregate of different
smaller
groups so that the method considers the majority winner to be
the broad-support candidate. The problem with this is that if that's
a
general property, then it might turn out that a Droop
quota can force
the election of a particular candidate in a
weighted voting method with
a lower threshold just by
pretending to be very unreasonable or to be
many different
smaller groups.
It certainly is possible for the
proof of concept method. For instance,
the L-first voters
can truncate after L, after which the outcome changes
from
{CS} to {LS}. Part of this, however, is due to that the method
above passes LNHelp but not LNHarm (because it's Bucklinesque and
because voters are assigned completely to their first preferences).
If
the strategy is particular to certain weighted
voting/tunable threshold
methods, then there's no problem.
But if it's general (and it might
intuitively be), that's
another matter.
If it is general, I can think of
three ways to keep weighted voting:
- Let the number of
seats/winners be adjustable.
- Accept the Droop quota.
- Use a (randomized) consensus method.
Some
combination of 1 and 3 might also be possible.
The
first option is to let the number of winners be adjustable. The
general idea would be to have the same threshold and if a party
clones
itself, it does get another winner - but the number
of winners also
increases so that there's no benefit. Or,
conversely (if one accepts the
Droop quota), a candidate who
gets more than a Droop quota's worth
removes as many seats
as he has Droop quotas. E.g. in the clone example
above,
without cloning, the outcome would then be {A, B}, and with
cloning, it would be {A1, A2, B}. Again, there's no benefit. Both of
these make weighted voting more like party list PR.
The second option is to just accept the Droop quota and use
a
multiwinner method as basis. The cloning is still
possible, but at least
one gets more varied winners without
cloning and there's no need to
engage in strategic
nomination. With IRV, a party could split itself too
thin by
overestimating its support, but that won't happen with say, STV.
A party just has to field enough candidates (say enough to fill the
council) and doesn't have to worry about fielding too
many.
The third option is to use consensus. If it's
an Asset variant, we could
just "stick the candidates
in a room and have them negotiate until they
agree"
with a supermajority, but there's an incentive for the status quo
to block the consensus. That can be fixed with randomized consensus -
some kind of variant of the methods Jobst and Forest Simmons
have
proposed[3]. Randomized consensus can be done either
before the election
(as a general method) or after (as a
variant of Asset), but the former
is much less likely to
work.
Basically, these methods consist of every
voter (candidates in case of
Asset) voting for a consensus
outcome as well as for a favorite outcome.
If fewer voters
than the threshold disagree about the consensus outcome,
then it is picked, otherwise a random favorite outcome is picked. As
random ballot is suboptimal but gives nobody an advantage,
so everybody
would want to find a consensus outcome to the
extent they can work
together to do so. The equivalent of a
cloning attack would be for a
majority candidate to stick to
his guns and only propose a council
consisting of his own
party. But if he tries to block the consensus,
then it falls
through to random ballot which favors nobody and only
degrades the quality of the solution.
Generalizing
this to multiwinner might be trickier because we want
something that with high probability returns a low-threshold
assignment
and that is strategically unbiased. The consensus
ballot can simply be a
set of winners. If fewer voters than
the threshold disagree about the
consensus, then it is
picked. But the fallback is hard. If we just do
"pick a
winner from voters' first preferences at random, eliminate,
repeat", then that favors Droop quota cloning because only one
of the
clones get eliminated at once. "Pick a proposed
winner set at random"
favors extreme outcomes. It would
be fair, but have very high variance:
one could end up with
a council controlled completely by a single party,
it's just
which party would control it that would be random in a
low-threshold unbiased manner.
[1] These are methods that never elect candidates with zero first
preference votes and where giving someone more first preferences
always
helps. I think the observation above holds for all of
these; it does at
least seem to hold for Plurality and
IRV.
[2] We could also argue that there should be a
threshold less than a
Droop quota by saying that if the
threshold is a Droop quota, then
(under strategy) the
outcome for weighted voting and unweighted voting
is the
same, so why bother with weights? Thus the point of having a
weight should be to make weighted voting be more representative with
fewer seats than ordinary unweighted voting can be. If, on
the other
hand, a Droop quota is good enough (and we just
want weighting to handle
excess beyond the Droop quota),
then we shouldn't use semi-majoritarian
methods but instead
unweighted multiwinner methods to decide upon the
winners in
the first stage.
[3]
++++++++++++++++++++++++++++++++++++++++++++++++++++++
Date: Mon, 13 Jul
2015 20:33:50 +0200
From: km_elmet@t-online.de
To:
Subject: Re: [EM] 19) APR:
Steve's 19th dialogue with Richard Fobes
On
07/12/2015 06:05 AM, Richard Fobes wrote:
On 6/30/2015
7:39 PM, steve bosworth wrote:
...
S: I accept that your method might mathematically at most
provide
'nearly full proportionality'. However, APR
offers the advantage of
'full proportionality'. Do
you dispute this?
Yes I dispute this. As I
have said before (and I think someone else
made a
similar point), your APR method does not achieve full
proportionality. Specifically, with APR, not every voter is
represented
by hisher first choice.
No method can achieve 100% percent proportionality. If you want
to say
that APR gets as close as is easily possible,
then I'll agree with that
on the condition that you also
acknowledge that VoteFair ranking also
can (if desired)
achieve that same high level of proportionality.
There's one aspect of this I was going to address in a reply of my
own
to Steve, but I have been busy. Still, I can at least
mention it here,
since it's relevant to what you're saying,
and then I'll try to get that
reply done at some point.
Suppose all voters rank every
candidate, and suppose you pick an
unpalatable set of
candidates as winners. Then you can assign voters to
each of
those winners: each voter is assigned to the winner that he
ranks first (of those in the winner set), like APR would do. (Call
that
procedure "weighted assignment".) The
candidates will have weights
proportional to their support
among the winning set. But this hardly
seems like a good
outcome, since the winning set only consists of
unpalatable
candidates.
Concretely: If we have
40: A > B > C
60: D > E > F
then
{AD} with 40% to A and 60% to D is better than {BE} with 40% to B
and 60% to E, even though in both cases, every voter's vote "counts"
in
the sense of influencing a winner's weight.
Thus simply assigning every voter to the winner he prefers the most
does
not in itself provide a good result if the method that
picks the winners
to begin with is lacking. And IRV is not
exactly the best of methods :)
One possible
Condorcet approach could be:
Define the number of
voters that are penalized when moving from one set
of
winners (say {ABC}) to another (say {DEF}) as the number of voters
who prefer someone in the first set to someone in the second set
(i.e.
ranks one of the former above one of the latter).
Say {ABC} beats {DEF} if fewer voters are penalized by going
from {DEF}
to {ABC} than by going from {ABC} to {DEF}.
Let a penalty CW be the set that beats every other.
Multiwinner IRV most likely does not pick penalty CWs.
Inasfar as
penalty CWs are good things, this is a mark
against using multiwinner
IRV for picking the winner set --
even though every vote contributes to
adjusting weights no
matter what winning set was picked, as long as
every voter
ranks every candidate. And if we pick a penalty CW using a
Condorcet method, there's nothing stopping us from calculating
weights
as above using that penalty CW set.
For that matter, you could use VoteFair proportional ranking to find
a
winning set, and then use weighted assignment as a second
stage if you
want weighted voting. Since weighted assignment
works for any set that
doesn't contain candidates nobody
ranks first among those in the set,
you can use the output
from IRV, VoteFair PR, STV, Schulze STV, or
whatnot
for the second stage. Some of these can be better than IRV-at
large: for instance, if I'm right about thresholds and that
multiwinner
IRV gives each party a number of seats equal to
its Droop quota support
in cloning equilibrium, then using
STV would directly give that kind of
proportionality whereas
multiwinner IRV would only do so when the
parties are all
strategizing. Of course, if Droop proportionality is
undesirable, then using STV would be bad, but so would using IRV be.
Sorry that I haven't been able to reply before this. Hopefully it didn't
cause too much of a problem!
By the way, my mail client says your posts are in the Windows-1254
format. Are you writing on a Turkish computer? If not, something might
be strange with your setup.
Your message source also states Content-Type: text/plain;
charset="windows-1254".
On 07/17/2015 09:54 PM, steve bosworth wrote:
Re: (4) APR: Steve's 4^th dialogue with Kristofer
From: election-methods-request@lists.electorama.com
Subject: Election-Methods Digest, Vol 133, Issue 2
To: election-methods@lists.electorama.com
Date: Thu, 2 Jul 2015 12:01:24 -0700
…....................................................
- Thresholded weighted multiwinner elections
(Kristofer Munsterhjelm)
Date: Wed, 01 Jul 2015 22:14:11 +0200
From: Kristofer Munsterhjelm km_elmet@t-online.de
To: Election Methods Mailing List election-methods@electorama.com
Subject: [EM] Thresholded weighted multiwinner elections
Message-ID: 55944A13.7060800@t-online.de
Content-Type: text/plain; charset=utf-8; format=flowed
Steve's questions will follow each element of what Kristofer wrote:
I think I see why the cloning attack is possible in two-stage weighted
voting. If I'm right, then it is possible to make voting methods that
produce results that fit weighted voting better -- at least when the
voters are honest. However, I'm not sure if it is possible at all if
enough voters are strategic.
Am I mistaken in believing that, in practice, APR's 'weighted
multiwinner elections' would not be vulnerable to the threats either of
effective 'cloning' or effective 'strategic voting'?
As a side note: the Duggan-Schwartz theorem implies that every
deterministic ranked voting method is sometimes vulnerable to strategic
voting, even if it's a multiwinner method rather than a single-winner
one. So every method is in some sense flawed; we just have to find good
ones. Since APR's method is a ranked multiwinner method and thus covered
by D-S, it can't be invulnerable to strategic voting. The question is
whether it's good enough.
As for the cloning attack, I specifically found it while analyzing APR's
voting method. So it's meant to work against APR's voting method
(semimajoritarian IRV). It is not quite as strong as I originally
thought, but would still lead to party list in an equilibrium. See below.
This practical invulnerability would seem to arise from the facts
that APR's election
of reps to a large national assembly would allow all citizen to rank
as few or as many of all the thousands of candidates in the country.
Accordingly, for example, the portion of all the perceived clones
would be elected who were discover to be, for example, among the 435
most popular candidates in the USA. Each elected candidate would
simply have a weighted vote in the assembly equal to the number of
votes that each had received directly or indirectly from citizens.
As I may have mentioned, we can abstract the two-stage voting method as
follows:
First you run a first stage which determines who the winners are. No
weighting is done at this stage.
Second, you assign each voter to the winner that he prefers the most of
the winners. E.g. if the winner set is {ABC} and a voter voted D>C>B>A,
then he is assigned to C.
Each winner gets a weight proportional to the number of voters assigned
to him.
(End of abstraction)
In APR, to elect k winners, the first stage is IRV until you have
eliminated all but k candidates. (E.g. to elect three winners, you
eliminate and redistribute first preferences until only three candidates
are left, and they are the winners).
The way I read you, you're saying that because the second stage is fair,
then the method as a whole is fair. That is, "each elected candidate
would simply have a weighted vote in the assembly equal to the number of
votes that each had received directly or indirectly from citizens", and
you also implicitly bring that up when you talk about wasted votes and
how APR doesn't waste votes.
But there's another way by which the method can be unfair. That is by
affecting the first stage. Say in a three-winner election example that a
lot of voters would be happy if E were elected, but the use of strategy
pushes E off the winning set entirely. E.g. voters who prefer A to E
strategize so that the winning set goes from {BCE} to {ABC}.
Now, the E-voters will contribute to the candidate they favor among A,
B, and C, but that doesn't make the fact that they preferred E go away.
Their vote isn't wasted among A, B, and C, but it's diminished by (or
degraded by) that they didn't get E.
In very simple terms: the first stage is "Determine what choices you get
to choose from", and the second stage is "Choose from the choices
given". The model is that the voters will choose, from those choices,
the choice they prefer, and that might work, but it can't make winners
out of non-winnerss. It needs the choices passed on from the first stage
to be good to begin with.
Thus, my cloning and strategy observations are directly focused on the
first stage. My "degraded voters" concept is also based on this
observation. I could construct observations for the second stage, but
that would currently only distract from the more serious ones in the
first stage.
At the same time, how could any citizen or group of citizens be able
to have enough reliable knowledge about how enough other citizens
will rank candidates in order to be confident enough of having a
'strategy' that would have the effect of producing anything other
than an honest result? In any case, what rational motive would any
citizen or group of citizens have in ranking other than their favored
candidates when their honest voting would instead guarantee that each
of their votes will only strengthen the elected reps they favor more
than the other reps?>
The incentive I have in mind is to push close competitors or minor
candidates off the winning set. If a candidate belonging to party A is
ranked second by a voter and the party can push off that voter's first
preference by cloning, then A wins. If a candidate belonging to party A
is ranked third by a voter and the party can push off the first two
candidates by cloning, then A wins, and so on.
A side effect of this is that it pushes the outcome towards one where
all candidates that have less than a Droop quota's worth of support are
excluded, because parties have nothing to lose by cloning to begin with.
As a result, the party that can pull off the most well-planned vote
allocation gains an advantage, all other things equal.
(IRV has other incentives for voters to not vote their favorites first,
but that's not part of the cloning problem, so I won't deal with them
here. Suffice to say that IRV, like most methods, fails the favorite
betrayal criterion.)
But first, coordination.
It's true that for the cloning attack to work, the supporters of the
party have to distribute evenly among the candidates that are part of
the party or conspiracy. However, due to the way that IRV works, if the
coordination fails, the party executing the attack loses nothing
compared to what would have happened if they did not clone to begin
with. Here's an example somewhat different from my last:
52: X > Y > Z > W
25: Y > W > Z > X
10: Z > W > X > Y
5: W > Y > X > Z
Three candidates to elect. W gets eliminated, the winning set becomes
{X, Y, Z}, and the weights are:
X: 52/92 = 56.5%
Y: 30/92 = 32.6%
Z: 10/92 = 10.9%
Now suppose that X would like to capture Z's weight. Since X has more
than two Droop quotas' worth of votes, it can do so by cloning:
26: X1 > X2 > Y > Z > W
26: X2 > X1 > Y > Z > W
25: Y > W > Z > X1 > X2
10: Z > W > X1 > X2 > Y
5: W > Y > X2 > X1 > Z
Now, first W and then Z is eliminated and the winning set becomes {X1,
X2, Y} with weights
X1: 36/92 = 39.1%
X2: 26/92 = 28.3%
Y: 30/92 = 32.6%
So the X party increased its share of the pie from 56.5% to 67.4% and
from a simple majority to a two thirds majority by cloning. Note how the
first stage weakens the second - the Z-voters' first preferences are no
longer counted, instead only their third preferences are.
But what would have happened if the coordination went badly? Then you
would have got something like this:
50: X1 > X2 > Y > Z > W
2: X2 > X1 > Y > Z > W
25: Y > W > Z > X1 > X2
10: Z > W > X1 > X2 > Y
5: W > Y > X2 > X1 > Z
The elimination order is X2 first, then W, and the winning set is {X, Y,
Z}. The second stage goes as above: no harm befalls X for having cloned.
That still leaves the question of how a party would coordinate their
voters. Note that the voters aligned with X don't need to know how the
non-X voters are voting.
How do they coordinate? In SNTV (as was used in Taiwan until 10 years
ago or so) the need for coordination was even greater, since fielding
too many clones could cost a party all of its seats. A similar need for
coordination has shown itself in Hare party list in Hong Kong. So we can
look at those to get some idea of how parties can coordinate. In Taiwan,
the strategies differed as the parties tried to find out what worked
best, but what they ended up doing in the end was:
- To find out how much support it has, Party X polls the electorate.
- Say it has three Droop quotas' worth. It thus fields three canidates.
- It then posts a newspaper ad saying "If your birthday is on the 1st to
10th of the month, vote for X1. If your birthday is on the 10th to the
20th of the month, vote for X2. Otherwise, vote for X3."
This gives a more or less even distribution (as there are about as many
months with 31 days as 30) and lets the voters coordinate the strategy.
See also https://en.wikipedia.org/wiki/Vote_allocation .
In APR, the situation is a little different. It never hurts to run more
clones as long as the voters spread their votes evenly among them. If
there are three seats or winner set positions, the party might field
three candidates, or field five if there are five seats. Say there are
three seats. Party X would proceed like this:
- It fields three ccandidates.
- It then posts a newspaper ad saying "If your birthday is on the 1st to
10th of the month, vote X1 > X2 > X3. If your birthday is on the 10th to
the 20th, vote X2 > X3 > X1. Otherwise, vote X3 > X1 > X2."
Again, the attack is on the first stage rather than the second stage. If
the set of winners passed from the first stage to the second is already
compromised, then the second stage can't compensate even if the second
stage would happen to be quite fair.
It might turn out that the only way of
making weighted voting work is through either varying the number of
winners (like in party list) [...]
Is not this what APR does, or have I misunderstood you here?.
Not quite, because the seats in party list aren't just for weighting
parties, but also for permitting more parties to be represented.
Here I'm going to simplify the example above so everybody bullet votes,
just to make the point obvious.
Say the voters vote for parties like this:
52: X
25: Y
10: Z
5: W
and say we have three seats. Webster produces the following allocation:
X: 2, Y: 1
That's the same outcome as if X had cloned in APR above. There are two
distinct winners: X and Y.
Now suppose that X tries to clone:
26: X1
26: X2
25: Y
10: Z
5: W
Webster produces the following allocation:
X1: 1, X2: 1, Y: 1
so the cloning has no effect. There are now three distinct winners (X1,
X2, and Y). The method adjusts the number of distinct winners who are
permitted onto the council, and that is what renders the cloning attack
above ineffective here. (This is a major reason why Webster is a better
party list method than SNTV.)
In contrast, APR has a fixed number of winners. If there are three
seats, it needs to fill them all up, hence it elects {X, Y, Z} in the
first case and {X1, X2, Y} in the second.
We have that APR's method goes from one set of winners to another set of
winners after cloning. So either one of those sets (or both) were wrong
to begin with, or the problem isn't a problem. In other words, the
responses I can see to this is:
A. The cloning attack is a problem and should be fixed, and {X, Y, Z} is
the correct outcome; three-seat APR should afford to be more diverse
than three-seat party list.
B. The cloning attack is a problem and should be fixed, and {X, Y} is
the correct outcome; the method should behave more like party list does.
Z has too little support to be represented anyway.
C. The cloning attack is not a problem since unweighted STV exhibits the
same thing.
The fix depends on which of these conclusions seem more right.
[...] or by an unconventional (nondeterministic) voting system or
the Asset version of this.
Is not this what APR does, or have I misunderstood you here?>
No; APR is not nondeterministic (randomized). Nor does it always go to
an Asset stage.
In the part you quoted, I was thinking about ways of making APR work if
you came to conclusion A. In particular, the asset version I mentioned
would be based on something like: give all the candidates initial
weights according to some election method, stick those candidates in a
room and let them move their weights around, and let them out again once
95% by initial weight agree on the distribution (and only as many
winners as you'd like have nonzero weight, etc). That approach, which is
a little like forming a government, would have a 5% implicit threshold
and would also favor the status quo. It might be possible to do better
and not favor any group, but finding a better method would require
research along Heitzig's lines.
First, why the cloning attack is possible: when we use (call them semi-
majoritarian[1]) methods like IRV or Plurality,if candidates
represent parties who can clone as many as they want, then I think the
strategic equilibrium gives each party a number of seats equal to their
number of Droop quotas. If we instead use an unweighted multiwinner
method (STV,
Schulze STV, etc), then the Droop proportionality criterion gives each
party at least their Droop quotas' worth in seats without strategy.
Simply, when the number of winners is fixed, the semi-majoritarian
methods have an implicit threshold of a Droop quota, and the unweighted
multiwinner methods have an explicit threshold of the same.
I understand that, above and below, you are exploring the logic of
these theoretical possibilities but why would we actually want to use
such needlessly less proportional and much more complicated methods than
those offered by APR for electing the legislative assembly of a large
nation?
How are they less proportional? Can you give an example where one of the
mentioned methods is less proportional than weighted IRV if the second
stage is the same?
Correct me if I am mistaken, but perhaps your next post (also copied
below) provides part of your answer to this question. It seems to worry
that APR might elect a so-called 'unpalatable set' of reps for the
assembly. If this is part of your answer, do you still accept that APR
would always have the best chance of electing an assembly that would be
entirely palatable to its voting citizens. This is because each citizen
could rationally see that she has a rep in the assembly who most likely
will both qualitatively and mathematically (proportionately) represent
her views?
No, I don't, because the first stage is suspect. I can go into detail
when we're done with the cloning.
Is your definition of 'unpalatable' something other than simply 'what
you happen subjectively to dislike?
It's closer to "what the voters would happen to dislike, were they aware
of the alternatives". (When the voters in Burlington showed their
dislike of IRV by repealing it, that wasn't because Warren Smith
subjectively disliked IRV.)
But this is only distantly related to the cloning problem, so perhaps we
should talk about the cloning first and then get to this afterwards?
That way, we won't spread too thin :-)
I'm not sure how many people here are fans of science fiction, but there
was a big brouhaha at this years awards (which I'll ignore), and one of
the results was the proposal of a new method of choosing winners:
Short Title: E Pluribus Hugo (Out of the Many, a Hugo)
Moved, to amend section 3.8 (Tallying of Nominations), section 3.9
(Notification and Acceptance), and section 3.11 (Tallying of Votes) as
follows:
Section 3.8: Tallying of Nominations.
3.8.1: Except as provided below, the final Award ballots shall list in
each category the five eligible nomineesreceiving the most nominations.
If there is a tie including fifth place, all the tied eligible nominees
shall be listed.determined by the following multi-round process
described in 3.8.8.
3.8.2: The Worldcon Committee shall determine the eligibility of
nominees and assignment to the proper category of works nominated in
more than one category.
3.8.3: Any nominations for “No Award” shall be disregarded.
3.8.4: If a nominee appears on a nomination ballot more than once in any
one category, only one nomination shall be counted in that category.
3.8.5: No nominee shall appear on the final Award ballot if it received
fewer nominations than five percent (5%) of the number of ballots
listing one or more nominations in that category, except that the first
three eligible nominees, including any ties, shall always be listed.
3.8.6: The Committee shall move a nomination from another category to
the work’s default category only if the member has made fewer than five
(5) nominations in the default category.
3.8.7: If a work receives a nomination in its default category, and if
the Committee relocates the work under its authority under subsection
3.2.9 or 3.2.10, the Committee shall count the nomination even if the
member already has made five (5) nominations in the more-appropriate
category.
/
3.8.8: The final Award ballots shall list in each category the eligible
finalists as determined by successive rounds of a two-phase elimination
process. In this process, each member gets a single nomination “point”
for each category, and that point will be divided equally among their
nominated works in that category.
3.8.8.1: Selection Phase: In each round, all the works having the least
number of points will be selected for the Elimination Phase (3.8.8.2).
If there is only one work with the least number of points, then all of
the works with the second-least number of points will be also be
selected for the Elimination Phase in addition to the lowest-point work.
3.8.8.2: Elimination Phase: Of the works identified in the Selection
Phase, the one(s) that appear on the fewest number of nomination ballots
will be removed from all nomination ballots for subsequent rounds as if
they had never appeared on any ballots.
3.8.8.4: Ties: If two or more works are tied for appearing on the fewest
number of nomination ballots, the tied work with the lowest point total
will be eliminated. If there is a tie for appearing on the fewest number
of nomination ballots as well as for lowest point total, then all
members of that tie will be eliminated. Should they deem it necessary to
do so in the future, the Hugo administrators are empowered to take
further measures to break this type of tie, provided those measures are
announced at the beginning of the nomination period for the Hugo Award.
3.8.8.5: If elimination would reduce the number of finalists to fewer
than the minimum number, then instead none of the works from that round
shall be eliminated, and all remaining works shall appear on the final
ballot, extending it if necessary.
3.8.8.6: Subsequent rounds begin by reallocating points as follows: All
works eliminated in previous rounds are removed from all nomination
ballots and treated as if they had never appeared on any nomination
ballot. Members’ points are then reallocated equally among their
remaining nominated works, if any./
Section 3.9: Notification and Acceptance.
3.9.1 Worldcon Committees shall use reasonable efforts to notify
thenominees/finalists/, or in the case of deceased or incapacitated
persons, their heirs, assigns, or legal guardians, in each category
prior to the release of such information. Eachnominee/finalist/shall be
asked at that time to either accept or decline the nomination. Ifthe
nominee/any finalist(s)/declines the nomination,
thatnominee/finalist(s)/shall not appear on the final ballot./In this
event, once all finalists have had the opportunity to decline, the
nomination system shall be re-run as described in Section 3.8 with the
declined nomination(s) removed from the nomination ballots on which they
appeared. The eligible finalists from this re-run shall be merged with
the remaining potential finalists from the original run. If this merge
would result in more than the maximum number of finalists, then the
ballot shall be extended to include the finalists from both the original
and the re-run of the nomination system. This procedure shall also be
used in the event that a finalist is deemed ineligible./
Section 3.11: Tallying of Votes.
3.11.4: The complete numerical vote totals, including all preliminary
tallies for first, second, … places, shall be made public by the
Worldcon Committee within ninety (90) days after the Worldcon.During the
same period the nomination voting totals shall also be published,
including in each category the vote counts for at least the fifteen
highest vote-getters and any other candidate receiving a number of votes
equal to at least five percent (5%) of the nomination ballots cast in
that category, but not including any candidate receiving fewer than five
votes./During the same period a record of all rounds of the selection
process for each category shall also be published.
/
It still needs to be ratified at next year's Worldcon, but I was
wondering about other's thoughts. Link, other info, and FAQ is here:
http://nielsenhayden.com/makinglight/archives/016262.html
Mike Rouse
On 08/24/2015 02:27 AM, Michael Rouse wrote:
I'm not sure how many people here are fans of science fiction, but there
was a big brouhaha at this years awards (which I'll ignore), and one of
the results was the proposal of a new method of choosing winners:
Short Title: E Pluribus Hugo (Out of the Many, a Hugo)
Moved, to amend section 3.8 (Tallying of Nominations), section 3.9
(Notification and Acceptance), and section 3.11 (Tallying of Votes) as
follows:
[snip]
So this is basically cumulative voting IRV? I suppose it's better than
ordinary IRV, but if they're using an Approval ballot, why not just use
Approval to begin with?
Do they want a proportional representation method or a majoritarian one?
The reference to avoiding slates seem to suggest to me that they want a
proportional representation method, or at least something that is closer
to a PR method.
As a positional elimination method, it could suffer path dependence.
Consider someone nominating (voting for) X, Y, and Z. Say now that Y is
very narrowly eliminated at some point, but if the person had voted for
X and Y alone, he would have given enough of his vote to Y to have kept
Y from being eliminated. So the claim that "[i]n other words, you can
safely nominate anything you feel is Hugo-worthy" doesn't seem to be
strictly true. You can safely nominate anything that is relatively
unpopular, but if it gets popular enough, it may draw enough support
away from the others you would also like to nominate.
If I were to construct a majoritarian ballot system with Approval
ballots, I would just use Approval. There's a similar "drawing away from
other popular candidates" problem (the chicken/Burr thing), but Approval
is much simpler and doesn't repeated iteration.
For PR, the question is much harder. With computers, you could use PAV,
sequential PAV or birational voting. However, the non-sequential ones
require a lot of recounts and are probably not feasible for manual
elections. Sequential ones are simpler but the proportionality might not
be obvious.
Thanks, I was thinking something similar, though you stated it much
better (grin).
I have been reading through the thread there (826 comments) and it looks
like others are suggesting Approval voting as well, though I'm not sure
if that suggestion was taken into account in the final draft. I might
have to write them and ask. :)
Mike
On 2015-08-24 04:06, Kristofer Munsterhjelm wrote:
On 08/24/2015 02:27 AM, Michael Rouse wrote:
I'm not sure how many people here are fans of science fiction, but
there
was a big brouhaha at this years awards (which I'll ignore), and one
of
the results was the proposal of a new method of choosing winners:
Short Title: E Pluribus Hugo (Out of the Many, a Hugo)
Moved, to amend section 3.8 (Tallying of Nominations), section 3.9
(Notification and Acceptance), and section 3.11 (Tallying of Votes) as
follows:
[snip]
So this is basically cumulative voting IRV? I suppose it's better than
ordinary IRV, but if they're using an Approval ballot, why not just use
Approval to begin with?
Do they want a proportional representation method or a majoritarian
one?
The reference to avoiding slates seem to suggest to me that they want a
proportional representation method, or at least something that is
closer
to a PR method.
As a positional elimination method, it could suffer path dependence.
Consider someone nominating (voting for) X, Y, and Z. Say now that Y is
very narrowly eliminated at some point, but if the person had voted for
X and Y alone, he would have given enough of his vote to Y to have kept
Y from being eliminated. So the claim that "[i]n other words, you can
safely nominate anything you feel is Hugo-worthy" doesn't seem to be
strictly true. You can safely nominate anything that is relatively
unpopular, but if it gets popular enough, it may draw enough support
away from the others you would also like to nominate.
If I were to construct a majoritarian ballot system with Approval
ballots, I would just use Approval. There's a similar "drawing away
from
other popular candidates" problem (the chicken/Burr thing), but
Approval
is much simpler and doesn't repeated iteration.
For PR, the question is much harder. With computers, you could use PAV,
sequential PAV or birational voting. However, the non-sequential ones
require a lot of recounts and are probably not feasible for manual
elections. Sequential ones are simpler but the proportionality might
not
be obvious.
As an addendum, they are calling this method “single divisible vote with
least popular elimination," which I haven't heard of before.
Mike
On 2015-08-24 04:06, Kristofer Munsterhjelm wrote:
On 08/24/2015 02:27 AM, Michael Rouse wrote:
I'm not sure how many people here are fans of science fiction, but
there
was a big brouhaha at this years awards (which I'll ignore), and one
of
the results was the proposal of a new method of choosing winners:
Short Title: E Pluribus Hugo (Out of the Many, a Hugo)
Moved, to amend section 3.8 (Tallying of Nominations), section 3.9
(Notification and Acceptance), and section 3.11 (Tallying of Votes)
as
follows:
[snip]
So this is basically cumulative voting IRV? I suppose it's better than
ordinary IRV, but if they're using an Approval ballot, why not just
use
Approval to begin with?
Do they want a proportional representation method or a majoritarian
one?
The reference to avoiding slates seem to suggest to me that they want
a
proportional representation method, or at least something that is
closer
to a PR method.
As a positional elimination method, it could suffer path dependence.
Consider someone nominating (voting for) X, Y, and Z. Say now that Y
is
very narrowly eliminated at some point, but if the person had voted
for
X and Y alone, he would have given enough of his vote to Y to have
kept
Y from being eliminated. So the claim that "[i]n other words, you can
safely nominate anything you feel is Hugo-worthy" doesn't seem to be
strictly true. You can safely nominate anything that is relatively
unpopular, but if it gets popular enough, it may draw enough support
away from the others you would also like to nominate.
If I were to construct a majoritarian ballot system with Approval
ballots, I would just use Approval. There's a similar "drawing away
from
other popular candidates" problem (the chicken/Burr thing), but
Approval
is much simpler and doesn't repeated iteration.
For PR, the question is much harder. With computers, you could use
PAV,
sequential PAV or birational voting. However, the non-sequential ones
require a lot of recounts and are probably not feasible for manual
elections. Sequential ones are simpler but the proportionality might
not
be obvious.
Election-Methods mailing list - see http://electorama.com/em for list
info
Jameson Quinn, who's on this list, was working with the Hugo awards to come
up with this system.
I believe he proposed simple systems first, but several wrinkles came up
which necessitated the complexity.
I'll email him and see if I can get him to chime in here.
On Mon, Aug 24, 2015 at 8:29 AM, mrouse1@mrouse.com wrote:
As an addendum, they are calling this method “single divisible vote with
least popular elimination," which I haven't heard of before.
Mike
On 2015-08-24 04:06, Kristofer Munsterhjelm wrote:
On 08/24/2015 02:27 AM, Michael Rouse wrote:
I'm not sure how many people here are fans of science fiction, but there
was a big brouhaha at this years awards (which I'll ignore), and one of
the results was the proposal of a new method of choosing winners:
Short Title: E Pluribus Hugo (Out of the Many, a Hugo)
Moved, to amend section 3.8 (Tallying of Nominations), section 3.9
(Notification and Acceptance), and section 3.11 (Tallying of Votes) as
follows:
[snip]
So this is basically cumulative voting IRV? I suppose it's better than
ordinary IRV, but if they're using an Approval ballot, why not just use
Approval to begin with?
Do they want a proportional representation method or a majoritarian one?
The reference to avoiding slates seem to suggest to me that they want a
proportional representation method, or at least something that is closer
to a PR method.
As a positional elimination method, it could suffer path dependence.
Consider someone nominating (voting for) X, Y, and Z. Say now that Y is
very narrowly eliminated at some point, but if the person had voted for
X and Y alone, he would have given enough of his vote to Y to have kept
Y from being eliminated. So the claim that "[i]n other words, you can
safely nominate anything you feel is Hugo-worthy" doesn't seem to be
strictly true. You can safely nominate anything that is relatively
unpopular, but if it gets popular enough, it may draw enough support
away from the others you would also like to nominate.
If I were to construct a majoritarian ballot system with Approval
ballots, I would just use Approval. There's a similar "drawing away from
other popular candidates" problem (the chicken/Burr thing), but Approval
is much simpler and doesn't repeated iteration.
For PR, the question is much harder. With computers, you could use PAV,
sequential PAV or birational voting. However, the non-sequential ones
require a lot of recounts and are probably not feasible for manual
elections. Sequential ones are simpler but the proportionality might not
be obvious.
Election-Methods mailing list - see http://electorama.com/em for list
info
Election-Methods mailing list - see http://electorama.com/em for list info
On 08/24/2015 05:29 PM, mrouse1@mrouse.com wrote:
As an addendum, they are calling this method “single divisible vote with
least popular elimination," which I haven't heard of before.
I haven't either; I think that "cumulative vote with elimination" or
"cumulative vote IRV" would have been an easier to understand term --
although not using the IRV name does have the benefit of denying FV
another source when claiming IRV use is widespread.
If I'd implement it in my voting simulator, it'd probably be called
"cumulative vote-elimination" or "cumulative voting-elimination" there,
but that might be too terse a name for other purposes :-)