The Frequency of Condorcet Winners in Real Non-Political Elections
Here is a paper I recently presented at the 61st Public Choice Society
Conference https://publicchoicesociety.org/conference/2024, containing
results from analysis of tens of thousands of polls run on the CIVS
system since 2003.
The Frequency of Condorcet Winners in Real Non-Political Elections
https://www.cs.cornell.edu/andru/papers/civs24/
Andrew C. Myers
Condorcet-consistent voting is attractive because it follows the
principle that the will of a majority of voters should not be denied.
However, it is in general possible that there is no Condorcet winner: a
cycle of candidates might exist in which each candidate is preferred to
the next. The possibility that such a cycle occurs, and the uncertainty
about how to handle it, have been an obstacle to the adoption of
Condorcet methods. This paper reports on the experience from CIVS, a
long-running open-source voting service that supports
Condorcet-consistent voting methods. Over a period of about twenty
years, users have conducted tens of thousands of polls using CIVS,
including many with real-world consequences. During this time, CIVS has
thus accumulated probably the largest existing corpus of data about how
Condorcet voting functions in practice. CIVS supports multiple
completion methods for handling cycles, but the data show that it
usually does not matter which completion method is used, because there
is rarely a cycle in polls with a large enough number of voters.
Full text here: https://www.cs.cornell.edu/andru/papers/civs24/
https://www.cs.cornell.edu/andru/papers/civs24/
Cheers,
-- Andrew
Oooh wow, this seems like a great paper—thank you for sharing! Do you
happen to have the code and data somewhere? Thanks!
On Sun, Mar 31, 2024 at 5:08 PM Andrew Myers andrew.myers@cornell.edu
wrote:
Here is a paper I recently presented at the 61st Public Choice Society
Conference https://publicchoicesociety.org/conference/2024, containing
results from analysis of tens of thousands of polls run on the CIVS system
since 2003.
The Frequency of Condorcet Winners in Real Non-Political Elections
https://www.cs.cornell.edu/andru/papers/civs24/
Andrew C. Myers
Condorcet-consistent voting is attractive because it follows the principle
that the will of a majority of voters should not be denied. However, it is
in general possible that there is no Condorcet winner: a cycle of
candidates might exist in which each candidate is preferred to the next.
The possibility that such a cycle occurs, and the uncertainty about how to
handle it, have been an obstacle to the adoption of Condorcet methods. This
paper reports on the experience from CIVS, a long-running open-source
voting service that supports Condorcet-consistent voting methods. Over a
period of about twenty years, users have conducted tens of thousands of
polls using CIVS, including many with real-world consequences. During this
time, CIVS has thus accumulated probably the largest existing corpus of
data about how Condorcet voting functions in practice. CIVS supports
multiple completion methods for handling cycles, but the data show that it
usually does not matter which completion method is used, because there is
rarely a cycle in polls with a large enough number of voters.
Full text here: https://www.cs.cornell.edu/andru/papers/civs24/
https://www.cs.cornell.edu/andru/papers/civs24/
Cheers,
-- Andrew
Election-Methods mailing list - see https://electorama.com/em for list
info
On 2024-04-01 02:07, Andrew Myers wrote:
Here is a paper I recently presented at the 61st Public Choice Society
Conference https://publicchoicesociety.org/conference/2024, containing
results from analysis of tens of thousands of polls run on the CIVS
system since 2003.
Thanks! I've added the paper to Electowiki:
https://electowiki.org/wiki/Condorcet_winner_criterion#Occurrences_in_real_elections.
Do you have any statistics on Smith set sizes for the non-CW elections?
-km
In other words, "Impartial Culture" simulations are highly misleading since
they give the impression that Condorcet Winners become increasingly rare as
the number of candidates increases.
On Sun, Mar 31, 2024, 5:08 PM Andrew Myers andrew.myers@cornell.edu wrote:
Here is a paper I recently presented at the 61st Public Choice Society
Conference https://publicchoicesociety.org/conference/2024, containing
results from analysis of tens of thousands of polls run on the CIVS system
since 2003.
The Frequency of Condorcet Winners in Real Non-Political Elections
https://www.cs.cornell.edu/andru/papers/civs24/
Andrew C. Myers
Condorcet-consistent voting is attractive because it follows the principle
that the will of a majority of voters should not be denied. However, it is
in general possible that there is no Condorcet winner: a cycle of
candidates might exist in which each candidate is preferred to the next.
The possibility that such a cycle occurs, and the uncertainty about how to
handle it, have been an obstacle to the adoption of Condorcet methods. This
paper reports on the experience from CIVS, a long-running open-source
voting service that supports Condorcet-consistent voting methods. Over a
period of about twenty years, users have conducted tens of thousands of
polls using CIVS, including many with real-world consequences. During this
time, CIVS has thus accumulated probably the largest existing corpus of
data about how Condorcet voting functions in practice. CIVS supports
multiple completion methods for handling cycles, but the data show that it
usually does not matter which completion method is used, because there is
rarely a cycle in polls with a large enough number of voters.
Full text here: https://www.cs.cornell.edu/andru/papers/civs24/
https://www.cs.cornell.edu/andru/papers/civs24/
Cheers,
-- Andrew
Election-Methods mailing list - see https://electorama.com/em for list
info
One of the interesting takeaways for me is something I haven't seen mentioned yet: IRV fails to pick a weak CW 6% of the time, conditional on one existing (which is almost always the case unless the number of voters is tiny).
On 3/31/24 20:07, Andrew Myers wrote:
Here is a paper I recently presented at the 61st Public Choice Society Conference https://publicchoicesociety.org/conference/2024, containing results from analysis of tens of thousands of polls run on the CIVS system since 2003.
The Frequency of Condorcet Winners in Real Non-Political Elections https://www.cs.cornell.edu/andru/papers/civs24/
Andrew C. Myers
Condorcet-consistent voting is attractive because it follows the principle that the will of a majority of voters should not be denied. However, it is in general possible that there is no Condorcet winner: a cycle of candidates might exist in which each candidate is preferred to the next. The possibility that such a cycle occurs, and the uncertainty about how to handle it, have been an obstacle to the adoption of Condorcet methods. This paper reports on the experience from CIVS, a long-running open-source voting service that supports Condorcet-consistent voting methods. Over a period of about twenty years, users have conducted tens of thousands of polls using CIVS, including many with real-world consequences. During this time, CIVS has thus accumulated probably the largest existing corpus of data about how Condorcet voting functions in practice. CIVS supports multiple completion methods for handling cycles, but the data show that it usually does not matter which completion
method is used, because there is rarely a cycle in polls with a large enough number of voters.
Full text here: https://www.cs.cornell.edu/andru/papers/civs24/ https://www.cs.cornell.edu/andru/papers/civs24/
Cheers,
-- Andrew
Election-Methods mailing list - see https://electorama.com/em for list info