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Any published scholarship discussing or describing the Center Squeeze effect?

RB
robert bristow-johnson
Wed, Feb 8, 2023 4:02 PM

Subject header says it all.  Do any of you know of or have a reference to any decent scholarship discussing the Center Squeeze effect that Hare RCV has?

There is a really stupid page at the Center for Election Science describing what they call "Center Squeeze" of FPTP.  But there is nothing in it about center squeeze.  It's about the problem of vote splitting with two clones that happen to be in the center.  There is nothing about it which demonstrates any bias against candidates in the center of the spectrum.  It's just about clones, wherever they lie on the spectrum.

I have always understood (and even put it in my paper) that Center Squeeze was is a problem of Hare RCV (IRV) and the source of the problem is that Hare RCV is opaque to second-choice votes until such votes are promoted to effectively first-choice and actually counted.  The centrist candidate is at a disadvantage because the centrist candidate can expect to receive a lot more second-choice votes from the Left and Right than those two candidates on the Left and Right can expect to receive from voters in the opposite wing.

Anyway, I am looking for a good scholarly reference, if one exists.

bestest,

robert

--

r b-j . _ . _ . _ . _ rbj@audioimagination.com

"Imagination is more important than knowledge."

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Subject header says it all. Do any of you know of or have a reference to any decent scholarship discussing the Center Squeeze effect that Hare RCV has? There is a really stupid page at the Center for Election Science describing what they call "Center Squeeze" of FPTP. But there is nothing in it about **center** squeeze. It's about the problem of vote splitting with two clones that happen to be in the center. There is nothing about it which demonstrates any bias against candidates in the *center* of the spectrum. It's just about clones, wherever they lie on the spectrum. I have always understood (and even put it in my paper) that Center Squeeze was is a problem of Hare RCV (IRV) and the source of the problem is that Hare RCV is opaque to second-choice votes until such votes are promoted to effectively first-choice and actually counted. The centrist candidate is at a disadvantage because the centrist candidate can expect to receive a lot more second-choice votes from the Left and Right than those two candidates on the Left and Right can expect to receive from voters in the opposite wing. Anyway, I am looking for a good scholarly reference, if one exists. bestest, robert -- r b-j . _ . _ . _ . _ rbj@audioimagination.com "Imagination is more important than knowledge." . . .
KM
Kristofer Munsterhjelm
Thu, Feb 9, 2023 4:23 PM

On 08.02.2023 17:02, robert bristow-johnson wrote:

Subject header says it all.  Do any of you know of or have a
reference to any decent scholarship discussing the Center Squeeze
effect that Hare RCV has?

There is a really stupid page at the Center for Election Science
describing what they call "Center Squeeze" of FPTP.  But there is
nothing in it about center squeeze.  It's about the problem of vote
splitting with two clones that happen to be in the center.  There is
nothing about it which demonstrates any bias against candidates in the
center of the spectrum.  It's just about clones, wherever they lie on
the spectrum.

I have always understood (and even put it in my paper) that Center
Squeeze was is a problem of Hare RCV (IRV) and the source of the problem
is that Hare RCV is opaque to second-choice votes until such votes are
promoted to effectively first-choice and actually counted.  The centrist
candidate is at a disadvantage because the centrist candidate can expect
to receive a lot more second-choice votes from the Left and Right than
those two candidates on the Left and Right can expect to receive from
voters in the opposite wing.

Anyway, I am looking for a good scholarly reference, if one exists.

The Electowiki page on center squeeze gives three, here:
https://electowiki.org/wiki/Center_squeeze#References

I couldn't find much otherwise. It seems that the term "center squeeze"
is not used much in the academic literature. The closest I could get by
using Google Scholar is these:

ZHANG, Jiahua. The Pathologies of Voting Schemes. 2020:
http://homepage.divms.uiowa.edu/~jones/voting/4980.2020/projects/zhang.pdf
This is a term project detailing different types of voting method
failures, including center squeeze. References RangeVoting and Jameson
Quinn's VSE stats.

CADDICK, Zachary A. Learning, Choice Consistency, and Individual
Differences in How People Think Elections Should be Decided. 2023. PhD
Thesis. University of Pittsburgh.
http://d-scholarship.pitt.edu/44049/1/2022_12_19%20ZAC%20Dissertation%20Manuscript.pdf
The dissertation is about who people consider to be the rightful winner
in hypothetical elections. (Caddick finds that most people point to the
Plurality winner - perhaps out of familiarity - although they also think
IRV and cardinal voting are more fair than Plurality.) Page 37 mentions
center squeeze as a weakness ("quirk") of Plurality and IRV, and page 39
shows the presentation of center squeeze given to the participants of
the study.

There's also James Green-Armytage's paper on nomination incentive, where
simulation results show that IRV produces an incentive to exit:
candidates can help an aligned faction by leaving. But similar to what
you say, that's more about cloning in general than it is about center
squeeze in particular.

I'm not sure where the exact term "center squeeze" comes from, but I
would guess Jan Kok (who was the first to use it on EM, in 2006) was
inspired by 1D Yee diagrams (like this one:
https://commons.wikimedia.org/wiki/File:Voteline_center_squeeze.png?useskin=vector
); and that the term itself was picked up by Warren Smith, and from
there by William Poundstone, who wrote "Gaming the Vote" in 2013.

-km

On 08.02.2023 17:02, robert bristow-johnson wrote: > > > Subject header says it all. Do any of you know of or have a > reference to any decent scholarship discussing the Center Squeeze > effect that Hare RCV has? > > There is a really stupid page at the Center for Election Science > describing what they call "Center Squeeze" of FPTP. But there is > nothing in it about **center** squeeze. It's about the problem of vote > splitting with two clones that happen to be in the center. There is > nothing about it which demonstrates any bias against candidates in the > *center* of the spectrum. It's just about clones, wherever they lie on > the spectrum. > > I have always understood (and even put it in my paper) that Center > Squeeze was is a problem of Hare RCV (IRV) and the source of the problem > is that Hare RCV is opaque to second-choice votes until such votes are > promoted to effectively first-choice and actually counted. The centrist > candidate is at a disadvantage because the centrist candidate can expect > to receive a lot more second-choice votes from the Left and Right than > those two candidates on the Left and Right can expect to receive from > voters in the opposite wing. > > Anyway, I am looking for a good scholarly reference, if one exists. The Electowiki page on center squeeze gives three, here: https://electowiki.org/wiki/Center_squeeze#References I couldn't find much otherwise. It seems that the term "center squeeze" is not used much in the academic literature. The closest I could get by using Google Scholar is these: ZHANG, Jiahua. The Pathologies of Voting Schemes. 2020: http://homepage.divms.uiowa.edu/~jones/voting/4980.2020/projects/zhang.pdf This is a term project detailing different types of voting method failures, including center squeeze. References RangeVoting and Jameson Quinn's VSE stats. CADDICK, Zachary A. Learning, Choice Consistency, and Individual Differences in How People Think Elections Should be Decided. 2023. PhD Thesis. University of Pittsburgh. http://d-scholarship.pitt.edu/44049/1/2022_12_19%20ZAC%20Dissertation%20Manuscript.pdf The dissertation is about who people consider to be the rightful winner in hypothetical elections. (Caddick finds that most people point to the Plurality winner - perhaps out of familiarity - although they also think IRV and cardinal voting are more fair than Plurality.) Page 37 mentions center squeeze as a weakness ("quirk") of Plurality and IRV, and page 39 shows the presentation of center squeeze given to the participants of the study. There's also James Green-Armytage's paper on nomination incentive, where simulation results show that IRV produces an incentive to exit: candidates can help an aligned faction by leaving. But similar to what you say, that's more about cloning in general than it is about center squeeze in particular. I'm not sure where the exact term "center squeeze" comes from, but I would guess Jan Kok (who was the first to use it on EM, in 2006) was inspired by 1D Yee diagrams (like this one: https://commons.wikimedia.org/wiki/File:Voteline_center_squeeze.png?useskin=vector ); and that the term itself was picked up by Warren Smith, and from there by William Poundstone, who wrote "Gaming the Vote" in 2013. -km