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Re: [EM] The AMS has switched from Ranked Pairs to Instant-Runoff Voting

MS
Markus Schulze
Thu, Oct 19, 2023 7:42 PM

Hallo,

Kristofer Munsterhjelm wrote (10 March 2023):

So the story seems to be that tht elections committee
replaced the Condorcet language with IRV language,
made various other changes, and the whole thing got
passed in one go. But this just pushes the question
back to: why did the Elections Committee remove Ranked
Pairs? The documents don't seem to answer this question.

The following explanation is now given:

We decided to switch because Condorcet can give you no
result: nobody would win. Instant Runoff is preferred
by most who use a ranked system. It's much easier to
read the results with Instant Runoff.

Hallo, Kristofer Munsterhjelm wrote (10 March 2023): > So the story seems to be that tht elections committee > replaced the Condorcet language with IRV language, > made various other changes, and the whole thing got > passed in one go. But this just pushes the question > back to: why did the Elections Committee remove Ranked > Pairs? The documents don't seem to answer this question. The following explanation is now given: > We decided to switch because Condorcet can give you no > result: nobody would win. Instant Runoff is preferred > by most who use a ranked system. It's much easier to > read the results with Instant Runoff. https://www.ams.ubc.ca/wp-content/uploads/2023/04/Council-Minutes-February-1-2023-Redacted.pdf Markus Schulze
KM
Kristofer Munsterhjelm
Thu, Oct 19, 2023 8:00 PM

On 2023-10-19 21:42, Markus Schulze wrote:

Hallo,

Kristofer Munsterhjelm wrote (10 March 2023):

So the story seems to be that tht elections committee
replaced the Condorcet language with IRV language,
made various other changes, and the whole thing got
passed in one go. But this just pushes the question
back to: why did the Elections Committee remove Ranked
Pairs? The documents don't seem to answer this question.

The following explanation is now given:

We decided to switch because Condorcet can give you no
result: nobody would win. Instant Runoff is preferred
by most who use a ranked system. It's much easier to
read the results with Instant Runoff.

This seems like a weird explanation. It's true that Condorcet isn't
always decisive, but Ranked Pairs is. And is a Sankey style transfer
diagram that much more easy to read than a Ranked Pairs pairwise
preference order?

But it is what it is, I guess.

-km

On 2023-10-19 21:42, Markus Schulze wrote: > Hallo, > > Kristofer Munsterhjelm wrote (10 March 2023): > > > So the story seems to be that tht elections committee > > replaced the Condorcet language with IRV language, > > made various other changes, and the whole thing got > > passed in one go. But this just pushes the question > > back to: why did the Elections Committee remove Ranked > > Pairs? The documents don't seem to answer this question. > > The following explanation is now given: > > > We decided to switch because Condorcet can give you no > > result: nobody would win. Instant Runoff is preferred > > by most who use a ranked system. It's much easier to > > read the results with Instant Runoff. > > https://www.ams.ubc.ca/wp-content/uploads/2023/04/Council-Minutes-February-1-2023-Redacted.pdf This seems like a weird explanation. It's true that Condorcet isn't always decisive, but Ranked Pairs is. And is a Sankey style transfer diagram that much more easy to read than a Ranked Pairs pairwise preference order? But it is what it is, I guess. -km
KV
Kevin Venzke
Fri, Dec 1, 2023 1:01 PM

Something I meant to comment on:

Le jeudi 19 octobre 2023 à 15:00:31 UTC−5, Kristofer Munsterhjelm km_elmet@t-online.de a écrit :

On 2023-10-19 21:42, Markus Schulze wrote:

The following explanation is now given:

  > We decided to switch because Condorcet can give you no
  > result: nobody would win. Instant Runoff is preferred
  > by most who use a ranked system. It's much easier to
  > read the results with Instant Runoff.

https://www.ams.ubc.ca/wp-content/uploads/2023/04/Council-Minutes-February-1-2023-Redacted.pdf

 
This seems like a weird explanation. It's true that Condorcet isn't
always decisive, but Ranked Pairs is. And is a Sankey style transfer
diagram that much more easy to read than a Ranked Pairs pairwise
preference order?
 
But it is what it is, I guess.

What I see is that the principle of Condorcet may have legitimacy, but a method that
ensures Condorcet doesn't necessarily obtain its own legitimacy just because of it.

Yes, RP would give them a decisive result, but they wanted to sign up for Condorcet,
not RP.

As far as I know they didn't even encounter a cycle in one of their elections.

I see this as a blow to the stance that it really doesn't matter how a method
proposes to resolve cycles. Whether one's theory is that Condorcet is the only
desideratum, or whether it's that cycles would not show up in practice, this is
probably wrong from the standpoint of getting people to buy into it. People need to
perceive the merits of the approach for all cases.

Kevin
votingmethods.net

Something I meant to comment on: Le jeudi 19 octobre 2023 à 15:00:31 UTC−5, Kristofer Munsterhjelm <km_elmet@t-online.de> a écrit : > On 2023-10-19 21:42, Markus Schulze wrote: > > The following explanation is now given: > > > >  > We decided to switch because Condorcet can give you no > >  > result: nobody would win. Instant Runoff is preferred > >  > by most who use a ranked system. It's much easier to > >  > read the results with Instant Runoff. > > > > https://www.ams.ubc.ca/wp-content/uploads/2023/04/Council-Minutes-February-1-2023-Redacted.pdf >  > This seems like a weird explanation. It's true that Condorcet isn't > always decisive, but Ranked Pairs is. And is a Sankey style transfer > diagram that much more easy to read than a Ranked Pairs pairwise > preference order? >  > But it is what it is, I guess. What I see is that the principle of Condorcet may have legitimacy, but a method that ensures Condorcet doesn't necessarily obtain its own legitimacy just because of it. Yes, RP would give them a decisive result, but they wanted to sign up for Condorcet, not RP. As far as I know they didn't even encounter a cycle in one of their elections. I see this as a blow to the stance that it really doesn't matter how a method proposes to resolve cycles. Whether one's theory is that Condorcet is the only desideratum, or whether it's that cycles would not show up in practice, this is probably wrong from the standpoint of getting people to buy into it. People need to perceive the merits of the approach for all cases. Kevin votingmethods.net