Rob Richie's latest anti-Approval FUD

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Clay Shentrup

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Dec 23, 2016, 2:47:36 AM12/23/16
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http://www.fairvote.org/new_lessons_from_problems_with_approval_voting_in_practice

New Lessons from Problems with Approval Voting in Practice

POSTED BY ROB RICHIE ON DECEMBER 14, 2016

Ranked choice voting (RCV, also called instant runoff voting) is a proven way to open up elections to give voters more voice and greater choice. RCV and traditional two-round runoff elections are the only single winner systems proven to uphold majority rule in meaningfully contested elections with real campaigns and reported results -- not only in governmental elections, where RCV and runoffs are widely used, but in literally thousands of private group and campus elections.

Yet there is a persistent group of online critics who espouse other voting methods and attribute to them a range of untested virtues. Because FairVote is the preeminent American research and advocacy group on voting methods, we are sometimes asked why we support RCV and stay neutral on these other methods. Our concerns focus on viability and workability.

Approval voting is a good example. In this system, every voter can indicate approval for as many candidates as they want, and the one with the highest rate of approval wins. There are uses of approval voting that can make sense -- like when a group of people deciding on what movie to watch. While mathematicians can like this system and its alleged likelihood of electing a consensus winner, my colleagues and I are highly skeptical of its use in candidate elections. Two factors stand out:

  • Viability and the issue of majority rule: If voters truly are free with their approvals in an approval voting election, it’s quite possible two or more candidates could earn more than half the vote. Indeed, it’s possible that a candidate whom well over half of voters see as a top choice could lose to someone who nobody sees as their top choice. Approval voting advocates defend such outcomes as fair, but it remains to be seen what voters would say.

  • Workability in the real world: In approval voting elections, you can’t indicate support for more than one candidate without support for a lesser choice potentially causing the defeat of your first choice. This transparent dilemma for voters trying to cast a smart vote has immediate consequences. Because most voters as a result of this problem will refrain from approving of more than one candidate, the system in practice ends up looking far more like a plurality voting election system than a majority system.

Approval voting has never faced voters on the ballot -- although it was repealed in 2009 by a vote of 81% of Dartmouth alumni after it was tried for electing trustees to the alumni board and contributed to a perception that tactical voters were getting an advantage over other voters. But we have evidence that suggests the problem of workability is very real, which is the focus of the rest of this analysis.

Reviewing the major single winner voting systems

Only three basic electoral systems are used in elections around the world to elect single winners in governmental elections -- for offices like president, governor, mayor and legislator in a single-winner district.

  • Plurality voting is a method where voters cast one vote, and the candidate with the most votes wins even if that candidate might be strongly opposed by a majority of voters.  This system often is termed “first past the post,” but that doesn’t describe the system nearly as well as “top of the heap.” It is used for most single winner elections in the United States, although for many elections we have primaries which narrow the field before the general election.

  • Runoff elections are methods where the winner must surpass a certain threshold of support  to win -- usually a majority of the vote. Voters have a single vote, and there is a second election in the event no candidate reaches the threshold. In the second round, only two candidates advance. Runoffs are used in most presidential elections around the world, in a handful  of congressional races, and in many primary and local elections in the United States. Generally, the “math-based” arguments used against ranked choice voting - like “non-monotonicity”  and not always electing the “Condorcet winner”  -- also apply to runoff elections.

  • Ranked choice voting combines features of plurality voting and runoff elections. Like plurality voting, there is a single election. Like runoff elections, a candidate must surpass a certain threshold of votes to win in the first round. Rather than ask voters to return for a second election, however, they are asked to rank candidates from their first choice to last (stopping when they are indifferent to the remaining candidates), and the those rankings can simulate an “instant runoff” between the two strongest candidates in the final round of counting. Ranked choice voting is used in several nations for high offices, in 12 cities and counties in the United States, and in hundreds of meaningfully contested non-governmental elections based on it being recommended by Robert’s Rules of Order as a backup to repeated voting in person.

There  are some minor variations in how these systems are used, but they collectively are the only systems used in public single winner elections for any governmental office at any level of government anywhere in the world.

Approval Voting Trials and Disappointments

Two recent uses of the approval voting method by the Independent Party of Oregon and the Independent Voters Network show that it has value in certain uses, but is a far more problematic electoral method than ranked choice voting for electing candidates in meaningfully contested elections. These uses show that tactical voters can flip outcomes, and, due to that reason, most voters treat the election like a traditional plurality voting election and vote for only one. While in competitive RCV elections for important offices some nine in ten voters will rank more than one candidate, in approval voting elections that number plunges to less than half indicating support for more than one candidate, and often far less.

One reason FairVote prefers ranked choice voting to approval is that with RCV, voters can freely rank back-up candidates without worrying that they will hurt their first choice. In our experience, fear about helping a second-choice defeating a first choice is often the most common worry among those less familiar with RCV. When RCV elections are taking place, it is therefore very important to emphasize that with RCV, ranking a second or later choice will never hurt your first choice; ranking more candidates instead gives you more power, because it means you will still be heard even if your first choice is too weak a candidate to have a chance to win.

Unfortunately, this important quality isn’t true with approval voting. Because votes are equally weighted and counted simultaneously, voting for a second candidate means you’re helping them just as much as your first choice. In an election that might be close, that means that indicating you “approve” of a second choice might lead to your favorite candidate losing to your second choice. For that reason, approval works well when voters are more likely to accept that possibility (like in a non-decisive straw poll or deciding among several generally acceptable options). But it works far less well in closely contested and decisive elections with multiple rival candidates campaigning. In those contexts, most people vote only for their favorite, raising many of the same issues with vote splitting and low plurality outcomes as ordinary vote-for-one plurality.

Approval voting is not used for any governmental elections anywhere in the world, and has limited history in elections where the results are reported and campaigns seriously debated – primarily a few student elections, internal elections within minor parties and NGO elections (although the latter often don’t report results, which means voters don’t learn anything  from the results beyond who wins.)

We’ve analyzed the results of approval voting elections before, and elections that have similar problems like the Bucklin system. Here’s an update based on two relatively high-profile uses this year.

Independent Party of Oregon Preference Poll

Last summer, the Independent Party of Oregon held an online primary among major presidential candidates using approval voting. It was a potentially important contest because the party would have offered the winner its ballot line in the November election if able to secure more than 50% support in the approval voting contest. But, as is the norm in meaningfully contested approval voting elections, most voters only cast a vote for only one candidate. With 1,549 total voters, the results were:

  • Bernie Sanders 31.38 % (488 votes)

  • Donald Trump 30.16 % (469 votes)

  • Hillary Clinton 23.92 % (372 votes)

  • Gary Johnson 16.01 % (249 votes)

  • John Kasich 12.22 % (190 votes)

  • Jill Stein 09.45 % (147 votes)

  • None of the Above 09.20 % (143 votes)

  • Ted Cruz 05.66 % (88 votes)

That's a total of 2,146 votes, meaning voters cast an average of 1.38 votes. The party reports that more than 70% of voters cast bullet votes, with varying bullet voting strategies reported:

  • Trump: Of 466 voters who backed him, 354 (76%) voted only for him.

  • Sanders: Of 488 voters who backed him, 193 (39.5%) voted only for him.

  • Clinton: Of 372 voters who backed her, 198 (53.2%) voted only for her.

The party reported additional data on voters for Sanders, Clinton and Trump. For example, of Sanders’ 488 voters:

  • 135 (27.7%) also voted for Clinton

  • 108 (22.1%) also voted for Stein

  • 76 (15.6%) also voted for Johnson

  • 44 (9.0%) also voted for Kasich

  • 24 (4.9%) also voted for Trump

  • 23 (4.7%) also voted for Cruz

  •  4 (0.8%) also (oddly) voted for “none of the above”

The bottom line is that approval voting did not come close to identifying a majority winner, with a key reason being that voters withheld preferences they almost certainly felt about other candidates. In contrast, consider that when FairVote and the College of William and Mary partnered on a YouGov poll of the views of 1,000 likely Republican voters on the 11 leading Republican candidate at the time of the Iowa caucuses, more than nine in ten respondentschose to rank every single candidate and hardly anyone voted for only a single person. The YouGov poll also showed a change in outcome, with Ted Cruz coming from well behind to defeat Donald Trump head-to-head.

Similarly, in ranked choice voting mayoral elections in the United States where there have been several candidates in a contested race and full data sets provided, nearly nine in 10 voters will rank a second choice, and about three in four will rank at least three. That participation provides a far richer set of information that allows contrasts between the top two candidates where the great majority of voters have indicated support for one of them.

For example, the Oregon primary result with approval voting makes this contest seem closer than it really is. Donald Trump lost by only 19 votes, but when looking at how few people were willing to approve of both Trump and another candidate compared to how many approved of  both Sanders and another candidate, it becomes clear that most of the nearly 70% of voters who did not cast a vote for Trump likely preferred several other candidates over him. If a runoff had been  held - or if the race had been conducted by ranked choice voting - Sanders would almost certainly have defeated Trump head-to-head easily.

Approval voting gave Trump a chance to win, but it also may have hurt Trump in one way - and one that the prospect of which would lead to even more bullet voting over time in approval voting elections. Among primary voters, 24 of them backed both Trump and Sanders. If 19 of  those 24 voters preferred Trump to Sanders, then those voters effectively helped defeat their favorite candidate.

It is exactly such fears that lead voters to withhold preferences when approval voting is tried in contested elections. We have seen that trend when approval voting is tried in contested non-governmental elections. Students at the University of Colorado and Dartmouth have been using approval voting, and winners in multi-candidates races for student body president now rarely receive more than 40% support. Here’s an excerpt from a September 2015 analysis from my colleague Drew Spencer Penrose.

Approval voting elections conducted at Dartmouth and the University of Colorado both frequently show most voters only voting for one, and candidates regularly winning with less than 40% approval. Dartmouth was particularly instructive, as it went straight from using ranked choice voting in six student body president elections in 2005-2010 to using approval voting in those elections from 2011-2015. In the six RCV elections, the average number of votes cast for the winner in the final round was 1,073, and only once did the RCV winner's vote total fall below 1,000.

In contrast, in the five approval voting elections at Dartmouth, the most votes a winner ever has received is 966 (last spring when only two people ran), and the average has dropped by more than 20% to 808. The great majority of voters keep voting for only one person, explaining why victors in multi-candidate races regularly win with less than 40%. One student body president won with just over 30%. We've seeing the same kind of results at the University of Colorado: every race with more than two candidates ends up with winners having less than half the votes, just as if a plurality vote system were in place.

Notably, the Independent Party also used approval voting for other ballot choices that showed where the system can be useful. The party asked voters to indicate their support for a range of potential measures relating to government transparency, again presenting an approval ballot. This time, with the same ballot design, voters cast nearly four votes per voter, with at least 66% support for all five proposals. In other words, once taken out of the candidate frame and any concern about a second choice hurting a first choice in a way that really mattered to them, voters used the exact same approval voting system in a way that allowed identification of the option that had the closest to consensus support (more than 87% supporting more lobbyist disclosure.) For less highly charged uses like this, approval voting can indeed have value -- but to assume it will carry over to candidate elections is an unproven and unlikely leap.

Similar Cautionary Results from Independent Voter Network Elections

The Independent Voter Network (IVN) also used approval voting in a less formal poll on July 15-24. 2016 among independent and independent-minded voters. They had nearly 32,000 responses to a survey in which participants first voted by plurality, then with approval voting.

Once again, the great majority of people cast only one vote in the approval voting contest, with about 1.25 votes per voter in the approval vote. In this case, the approval voting contest flipped the outcome in a way that shows why the number of approvals would almost certainly decline in a real election where voters really thought about how they might vote. Here were the results as reported by IVN.

Plurality Vote:

  • Gary Johnson35%

  • Jill Stein31%

  • Donald Trump13%

  • Hillary Clinton 9%

  • Write-in12%

Approval vote:

  • Jill Stein49%

  • Gary Johnson47%

  • Donald Trump16%

  • Hillary Clinton13%

  • Write-insNot allowed/reported

With plurality voting, the results add up to 100%, with one person per vote. With approval voting, they add up to 125%, given the average of 1.25 voters per voter. When compared to the first round, Trump only picked up 3% when voters had approval voting, and Clinton picked up only 4%. The big beneficiaries were Stein and Johnson, with Stein rising from 31% to 49% and Johnson 35% to 47%.

But here’s the rub -- and it’s one similar to the Trump-Sanders dynamic in Oregon.  If just over 2% of her increase came from Gary Johnson backers, that means their decision to approve of both candidates led directly to the victory of a Green Party candidate over a Libertarian. In a real election with polls or even just discussions of such a potential outcome, far fewer people would have approved of both Stein and Johnson – and indeed, overall likely even fewer people would have voted for more than one person.

As IVN points out, the approval voting contest would be a useful measure of which candidate should be considered to be in the presidential debates. Right now, the Commission on Presidential Debates limits participation to candidates with 15% support in the polls, and approval voting polling would give more candidates a chance to surpass that threshold. Approval voting can work in pre-election polls, but in an actual election, its downsides becomes highly problematic.

These examples help to illuminate why FairVote prefers ranked choice voting for decisive public elections. Voters can freely rank second and later choice candidates, and they do. It gives voters greater voice than plurality elections. The elections are more participatory and efficient than runoffs. Social scientists continue to experiment with new ideas for election methods, but for now the practical options for policymakers include plurality, runoffs, and RCV. Ranked choice voting is the best option.

Warren D Smith

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Dec 23, 2016, 4:49:13 PM12/23/16
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> Ranked choice voting (RCV, also called instant runoff voting) is a proven
--well, I have proof it delivers pathologies, and I have proof the Australians
want to get rid of it. I don't think that was the kind of "proof"
Richie had in mind, but
since he never stated any kind of proof, I do not know for sure.

> Because FairVote
> is the preeminent American research and advocacy group on voting methods,

--I did not realize they did "research." I know they output "lies."
In fact, the very name "ranked choice voting" is used by them in a
deceptive manner.

> we are sometimes asked why we support RCV and stay neutral on these other
> methods.

--I did not realize they "stayed neutral."

> Viability and the issue of majority rule: If voters truly are free with
> their approvals in an approval voting election, it’s quite possible two
> or
> more candidates could earn more than half the vote. Indeed, it’s possible
>
> that a candidate whom well over half of voters see as a top choice could
>
> lose to someone who nobody sees as their top choice.
--true.
> Approval voting
> advocates defend such outcomes as fair, but it remains to be seen what
> voters would say.
--"what voters would say"? Well, approval was used for over 50 years
to elect the members of parliament of Greece. I daresay those
voters said something. It does not "remain to be seen" what they said,
since they already said it. It does remain to be seen whether Rob Richie
will ever try to figure out what they said. Or admit their existence.

> Workability in the real world: In approval voting elections, you can’t
> indicate support for more than one candidate without support for a lesser
>
> choice potentially causing the defeat of your first choice. This
> transparent dilemma for voters trying to cast a smart vote has immediate
>
> consequences. Because most voters as a result of this problem will
> refrain
> from approving of more than one candidate, the system in practice ends up
>
> looking far more like a plurality voting election system than a majority
>
> system.
--consulting http://www.rangevoting.org/FrenchStudy.html
the table of #approved indicates that the number of voters who
"refrained from approving of more than one candidate"
was 36+287=323.
The number who did approve more than one was
569+783+492+258+94+40+16+6+1+5=2264.
Therefore, it is false to say that "most" will "refrain
approving of more than one candidate."

> Approval voting has never faced voters on the ballot
--as we said above, Approval was used by Greece for over 50 years to elect its
members of parliament. Therefore, this claim by Richie was false.

> One reason FairVote prefers ranked choice voting to approval is that with
> RCV, voters can freely rank back-up candidates without worrying that they
> will hurt their first choice. In our experience, fear about helping a
> second-choice defeating a first choice is often the most common worry among
>
> those less familiar with RCV. When RCV elections are taking place, it is
> therefore very important to emphasize that with RCV, ranking a second or
> later choice will never hurt your first choice; ranking more candidates
> instead gives you more power, because it means you will still be heard even
>
> if your first choice is too weak a candidate to have a chance to win.
>
> Unfortunately, this important quality isn’t true with approval voting.
> Because votes are equally weighted and counted simultaneously, voting for a
>
> second candidate means you’re helping them just as much as your first
> choice. In an election that might be close, that means that indicating you
> “approve” of a second choice might lead to your favorite candidate losing
> to your second choice. For that reason, approval works well when voters are
>
> more likely to accept that possibility (like in a non-decisive straw poll
> or deciding among several generally acceptable options). But it works far
> less well in closely contested and decisive elections with multiple rival
> candidates campaigning. In those contexts, most people vote only for their
> favorite, raising many of the same issues with vote splitting and low
> plurality outcomes as ordinary vote-for-one plurality.
--there actually is an objective and measurable meaning one could
assign to Richie's purposely vague term "works well":
Bayesian Regret. Approval outperforms IRV in Bayesian Regret testing.

Richie finally goes on to consider some actual data from some polls & stuff.
That might be interesting to look at, if we can acquire that data.

--
Warren D. Smith
http://RangeVoting.org <-- add your endorsement (by clicking
"endorse" as 1st step)

Steve Cobb

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Dec 24, 2016, 4:44:02 AM12/24/16
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RR is just grumpy because all three of the essays in response to his recent Cato piece were critical of IRV, and two were pro-AV:

Aaron Wolf

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Dec 24, 2016, 11:46:48 AM12/24/16
to The Center for Election Science

One reason FairVote prefers ranked choice voting to approval is that with RCV, voters can freely rank back-up candidates without worrying that they will hurt their first choice. In our experience, fear about helping a second-choice defeating a first choice is often the most common worry among those less familiar with RCV. When RCV elections are taking place, it is therefore very important to emphasize that with RCV, ranking a second or later choice will never hurt your first choice; ranking more candidates instead gives you more power, because it means you will still be heard even if your first choice is too weak a candidate to have a chance to win.


This is so crafty, it's dishonest. Sure, marking your second choice can't hurt your first choice. But marking your first choice who still loses anyway *can* very likely hurt the prospects of your second choice. If Rob isn't willing to himself acknowledge the downsides to instant-runoff, he loses all credibility as a source. To honestly present any argument, one has to acknowledge the *actual* criticisms and not just use straw-man arguments.

> you will still be heard even if your first choice is too weak a candidate to have a chance to win

That part is the outright lie. Sure, when your 1st choice knocks our your 2nd choice in the 1st round, you could at least argue that marking the 2nd choice didn't hurt your 1st choice (who never had a chance anyway), but when your 1st choice knocks out your 2nd choice, you cannot still be heard if your 1st choice has no chance. You are not heard. Your vote is thrown out.

Warren D Smith

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Dec 24, 2016, 1:52:35 PM12/24/16
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In IRV, voting for your first choice cannot hurt your 2nd choice?

Well, it can hurt your first choice. Due to non-monotonicity:
http://rangevoting.org/Monotone.html


Plus there's this little problem:
#voters their vote
5 F>S>T>B
3 S>T
6 T>S
4 B
In the above IRV election, those 10 voters in the top line foolishly
voted for their First choice F.
Their Second choice S therefore is eliminated in round #1.
(If they had betrayed F, then S
would win the election after B and F were eliminated.)
Then B loses, then F, resulting in T WINNING.

So yes, voting for F did hurt S.

Warren D Smith

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Dec 24, 2016, 8:21:12 PM12/24/16
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Actually, this little episode in the Rob Richie annals of bullshit
gives us an excuse to summarize the situation.

For short, let "A hurts B" mean (in some voting system)
"there exists an election where by indicating your
Ath choice, you hurt your Bth choice (and asterisk:
if you prefer A over B then 'A winning' does
not count as 'hurting' B, it is just 'the natural course of events')."

problem IRV approval
1 hurts 1? yes no
1 hurts 2? yes no
2 hurts 1? no yes
2 hurts 2? yes no

Rob Richie either is unaware of this little table, or
is aware but considers it to favor IRV over approval.

Your opinion may differ.

Clay Shentrup

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Dec 25, 2016, 2:05:17 PM12/25/16
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That table is very clever, Warren. I'm going to use it.

Toby Pereira

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Dec 25, 2016, 3:37:17 PM12/25/16
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It's a very simple demonstration of why IRV's later-no-harm compliance is not the great everything-trumper that some might think.

Mark Frohnmayer

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Dec 26, 2016, 3:18:03 PM12/26/16
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If you haven't already, check out Statistical Evaluation of Voting Rules by Green-Armytage, Tideman and Cosman ( http://jamesgreenarmytage.com/strategy-utility.pdf ) 

They specifically tested "bullet voting":
 
5.1-5.2. Range voting and normalized range voting
This algorithm tests whether 𝑞 wins if all strategic voters give 𝑞 the maximum rating, and all other candidates the minimum rating.

5.3. Approval voting
This algorithm tests whether 𝑞 wins if all strategic voters approve only candidate 𝑞.

In their simulations, Range, Normalized Range, and Approval all showed pretty significant vulnerability to this simple strategy, which would seem to be the first science I've seen that corroborates FairVote's theories on this front.

Would love to hear Warren/Clay weigh in on this paper's approach.

On Sun, Dec 25, 2016 at 12:37 PM 'Toby Pereira' via The Center for Election Science <electio...@googlegroups.com> wrote:
It's a very simple demonstration of why IRV's later-no-harm compliance is not the great everything-trumper that some might think.

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Warren D Smith

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Dec 26, 2016, 3:48:07 PM12/26/16
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On 12/26/16, Mark Frohnmayer <mark.fr...@gmail.com> wrote:
> If you haven't already, check out Statistical Evaluation of Voting Rules by
> Green-Armytage, Tideman and Cosman (
> http://jamesgreenarmytage.com/strategy-utility.pdf )

--I haven't read the paper, since last time I tried, I failed to obtain a
readable pdf.

> They specifically tested "bullet voting":
>
> 5.1-5.2. Range voting and normalized range voting
> This algorithm tests whether 𝑞 wins if all strategic voters give 𝑞 the
> maximum rating, and all other candidates the minimum rating.

--note, if so. these voting systems become equivalent to plain plurality.

> 5.3. Approval voting
> This algorithm tests whether 𝑞 wins if all strategic voters approve only
> candidate 𝑞.

--same note.

> In their simulations, Range, Normalized Range, and Approval all showed
> pretty significant vulnerability to this simple strategy, which would seem
> to be the first science I've seen that corroborates FairVote's theories on
> this front.

--well, duh. We do not need simulations to see that these
voting systems all become equivalent to plain plurality voting
if voters all act this way.

Perhaps we should simulate IRV under the assumption that all voters rank
only their top choice, and do not rank anybody else?
I wonder what it would do then?

Jameson Quinn

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Dec 26, 2016, 4:18:18 PM12/26/16
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I have critiques of the approach they used there, but overall I think it was a useful advance. I'll expand on this when I have some time.

2016-12-26 15:17 GMT-05:00 Mark Frohnmayer <mark.fr...@gmail.com>:
If you haven't already, check out Statistical Evaluation of Voting Rules by Green-Armytage, Tideman and Cosman ( http://jamesgreenarmytage.com/strategy-utility.pdf ) 

They specifically tested "bullet voting":
 
5.1-5.2. Range voting and normalized range voting
This algorithm tests whether 𝑞 wins if all strategic voters give 𝑞 the maximum rating, and all other candidates the minimum rating.

5.3. Approval voting
This algorithm tests whether 𝑞 wins if all strategic voters approve only candidate 𝑞.

In their simulations, Range, Normalized Range, and Approval all showed pretty significant vulnerability to this simple strategy, which would seem to be the first science I've seen that corroborates FairVote's theories on this front.

Would love to hear Warren/Clay weigh in on this paper's approach.
On Sun, Dec 25, 2016 at 12:37 PM 'Toby Pereira' via The Center for Election Science <electionscience@googlegroups.com> wrote:
It's a very simple demonstration of why IRV's later-no-harm compliance is not the great everything-trumper that some might think.

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Mark Frohnmayer

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Dec 26, 2016, 5:21:48 PM12/26/16
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--I haven't read the paper, since last time I tried, I failed to obtain a
readable pdf.

The one on Green-Armytage's site isn't paywalled - opens for me...
 

Perhaps we should simulate IRV under the assumption that all voters rank
only their top choice, and do not rank anybody else?
I wonder what it would do then?

In this case they were specifically attempting to measure a voting system's resistance to strategy:

"In this paper we define resistance to strategy operationally as the likelihood that sincere voting will result in an outcome that no group of voters will be able to change to their mutual advantage by changing their votes."

"For each election, we must determine whether there is any candidate, q, other than the sincere winner, w, such that the voters who prefer to can change their ballots in any way and thereby change the winner to q. R is defined as the share of elections in which this is not the case."

They use different strategy algorithms for each voting system. The bullet voting approach in IRV won't result in a strategic advantage, but they do show that in a significant number of Range, Normalized Range and Approval elections that strategic bullet voting can change the outcome of the election in the favor of the strategic voters.

Warren D Smith

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Dec 26, 2016, 6:11:08 PM12/26/16
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On 12/26/16, Mark Frohnmayer <mark.fr...@gmail.com> wrote:
--oh, that's a rather poor measure of "strategy resistance" rather
similar to the one in
Tideman's book that I had criticized:
http://rangevoting.org/TidemanRev.html

but it is correct that "bullet voting" is one way that one (same-kind-of-voter)
group could use to alter the election, assuming all other voters do nothing,
which will always work (for range & approval) if anything works, at least
if the one guy they approve is the right guy.

Incidentally, bullet voting also converts SRV to plurality voting (right?).

A better strategy which also has the "works if anything does"
property is "threshold voting" where
the group gives all candidates above threshold max, all others
min, and their location for the threshold is chosen to be one
that works best (which might be non-unique).
This also always works (if anything works)
to improve election result, and by as much as possible.
But it is "better" in the sense it is more-immune to changes in
their underlying imperfect knowledge of what is going on...

Mark Frohnmayer

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Dec 26, 2016, 8:28:04 PM12/26/16
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On Mon, Dec 26, 2016 at 3:11 PM Warren D Smith 
Incidentally, bullet voting also converts SRV to plurality voting (right?).

Yes. IRV, Approval, SRV all become honest plurality with bullet voting.

That said, I would expect that SRV would have a dramatically higher resistance to bullet voting as a strategic way to change an election outcome versus Approval or Range. Bloc bullet voting would improve the odds of a candidate getting into the runoff, but it won't give your favorite candidate any advantage in winning the runoff step, and is risky because you may be artificially promoting a weaker candidate.

William Waugh

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Dec 26, 2016, 9:42:50 PM12/26/16
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On Saturday, December 24, 2016 at 11:46:48 AM UTC-5, Aaron Wolf wrote:

One reason FairVote prefers ranked choice voting to approval is that with RCV, voters can freely rank back-up candidates without worrying that they will hurt their first choice. In our experience, fear about helping a second-choice defeating a first choice is often the most common worry among those less familiar with RCV. When RCV elections are taking place, it is therefore very important to emphasize that with RCV, ranking a second or later choice will never hurt your first choice; ranking more candidates instead gives you more power, because it means you will still be heard even if your first choice is too weak a candidate to have a chance to win.


This is so crafty, it's dishonest. Sure, marking your second choice can't hurt your first choice. But marking your first choice who still loses anyway *can* very likely hurt the prospects of your second choice.

Do the critiques of IRV also apply to The Mother of All Voting Systems

Clay Shentrup

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Dec 26, 2016, 11:10:13 PM12/26/16
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On Monday, December 26, 2016 at 3:11:08 PM UTC-8, Warren D. Smith (CRV cofounder, http://RangeVoting.org) wrote:
--oh, that's a rather poor measure of "strategy resistance" rather
similar to the one in Tideman's book that I had criticized:
   http://rangevoting.org/TidemanRev.html

Indeed, and I tried to make this point in a layman friendly visual manner here via graph.

Clay Shentrup

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Dec 26, 2016, 11:11:02 PM12/26/16
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On Monday, December 26, 2016 at 5:28:04 PM UTC-8, Mark Frohnmayer wrote:
I would expect that SRV would have a dramatically higher resistance to bullet voting as a strategic way to change an election outcome versus Approval or Range.

But bullet voting isn't a generally best strategy in the first place, which is why this whole argument is rather moot.

Mark Frohnmayer

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Dec 26, 2016, 11:36:59 PM12/26/16
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The recent paper has an upgraded metric of strategy resistance than what Warren criticized in the book review. For example, the plurality presidential spoiler scenario is accounted for in their measure of R, and Plurality gets a low score as a consequence (like 0.77). 

From the paper "Panel A shows the widest picture of the data: random dictator has 100% resistance to strategy but just 52% under utilitarian efficiency, while range voting has 100% utilitarian efficiency but is vulnerable to manipulation in over 80% of cases."

Clay Shentrup

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Dec 27, 2016, 12:31:09 AM12/27/16
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On Monday, December 26, 2016 at 8:36:59 PM UTC-8, Mark Frohnmayer wrote:
From the paper "Panel A shows the widest picture of the data: random dictator has 100% resistance to strategy but just 52% under utilitarian efficiency, while range voting has 100% utilitarian efficiency but is vulnerable to manipulation in over 80% of cases."

Vulnerability to manipulation is only relevant insofar as it affects utility. So they should just show us Bayesian Regret figures and stop talking about "vulnerability to manipulation".

Warren D Smith

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Dec 27, 2016, 10:05:17 AM12/27/16
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yes, Bayesian Regret (in the presence of possibly-strategic voters)
is what we truly want to measure, and "vulnerability to manipulation"
isn't -- although the latter is related to part of the former.

but anyhow, it sounds like they have advanced vs what Tideman had been
doing before.

Mark Frohnmayer

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Dec 27, 2016, 1:58:09 PM12/27/16
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This is where the disconnect lies between the science lens and the actual felt experience of the voters. If a voting system is highly susceptible to this measure of manipulation (some subset of voters who got an honest outcome they didn't love can collude strategically to change the outcome in their favor), it's going to be a harder reform to pass, even if the manipulated outcome/normal outcome average have a lower Bayesian Regret than some other system.

For example, the Oregon League of Women Voters cites this recent paper as a reason why Range voting shouldn't really be considered a viable option: http://lwvor.org/election-methods-study-update-2016/ (it's a good broad survey, but there are some critical errors in there).

It's really only for this reason that I'm interested in re-running the same simulation (and bullet-voting strategy) with SRV.


Aaron Wolf

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Dec 28, 2016, 12:57:35 PM12/28/16
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On Tuesday, December 27, 2016 at 10:58:09 AM UTC-8, Mark Frohnmayer wrote:
This is where the disconnect lies between the science lens and the actual felt experience of the voters. If a voting system is highly susceptible to this measure of manipulation (some subset of voters who got an honest outcome they didn't love can collude strategically to change the outcome in their favor), it's going to be a harder reform to pass, even if the manipulated outcome/normal outcome average have a lower Bayesian Regret than some other system.

For example, the Oregon League of Women Voters cites this recent paper as a reason why Range voting shouldn't really be considered a viable option: http://lwvor.org/election-methods-study-update-2016/ (it's a good broad survey, but there are some critical errors in there).

It's really only for this reason that I'm interested in re-running the same simulation (and bullet-voting strategy) with SRV.


Furthermore, even if actual voters don't overreact to the strategic issue, the fact that FairVote et al makes a big stink about it means that addressing it makes SRV more politically viable. Similarly, I don't care at all about the concept of ranking as a concept. Rating candidates is just fine. But given that some people are hung-up on preferring the concept of ranking, SRV becomes politically sensible because it can be described as including a ranking element. I don't believe most voters care about any of these issues all that much since nothing really surprising ever happens with score voting, but voters who don't care will still say things like "oh, I read somewhere that score voting is not good" and "yeah, someone who studied this told me that ranking is better".

Warren D Smith

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Jan 14, 2017, 2:23:14 PM1/14/17
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