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Re: [EM] Scatter plot of clone independence versus IIA

MS
Markus Schulze
Sun, Jun 27, 2021 6:15 PM

Hallo,

I recommend the following formulation for the fourth category:

Suppose A won before cloning.
Suppose A is cloned to A(1),...,A(n).
Suppose A(1) wins when the used election method is applied only to
{A(1),...,A(n)}.
Then A(1) wins after.

Markus Schulze

Hallo, I recommend the following formulation for the fourth category: Suppose A won before cloning. Suppose A is cloned to A(1),...,A(n). Suppose A(1) wins when the used election method is applied only to {A(1),...,A(n)}. Then A(1) wins after. Markus Schulze
V
VoteFair
Fri, Jul 2, 2021 12:32 AM

On 6/27/2021 11:15 AM, Markus Schulze wrote:

Hallo,

I recommend the following formulation for the fourth category:

Suppose A won before cloning.
Suppose A is cloned to A(1),...,A(n).
Suppose A(1) wins when the used election method is applied only to
{A(1),...,A(n)}.
Then A(1) wins after.

Markus Schulze

I am not understanding what you are suggesting.

It sounds like you want to sub-divide the fourth category into these two
sub-categories:

  • A wins before cloning, A(1) wins after cloning, and A(1) wins if only
    the clones participate.

  • A wins before cloning, A(1) wins after cloning, but A(1) does not win
    if only the clones participate.

Do we need to distinguish between these two cases?

It seems to me that any of the clones winning instead of the original
similar candidate is a case of the clone displacing the original candidate.

Richard Fobes

On 6/27/2021 11:15 AM, Markus Schulze wrote: > Hallo, > > I recommend the following formulation for the fourth category: > > Suppose A won before cloning. > Suppose A is cloned to A(1),...,A(n). > Suppose A(1) wins when the used election method is applied only to > {A(1),...,A(n)}. > Then A(1) wins after. > > Markus Schulze I am not understanding what you are suggesting. It sounds like you want to sub-divide the fourth category into these two sub-categories: * A wins before cloning, A(1) wins after cloning, and A(1) wins if only the clones participate. * A wins before cloning, A(1) wins after cloning, but A(1) does not win if only the clones participate. Do we need to distinguish between these two cases? It seems to me that any of the clones winning instead of the original similar candidate is a case of the clone displacing the original candidate. Richard Fobes
KM
Kristofer Munsterhjelm
Fri, Jul 2, 2021 1:40 PM

On 02.07.2021 02:32, VoteFair wrote:

On 6/27/2021 11:15 AM, Markus Schulze wrote:

Hallo,

I recommend the following formulation for the fourth category:

Suppose A won before cloning.
Suppose A is cloned to A(1),...,A(n).
Suppose A(1) wins when the used election method is applied only to
{A(1),...,A(n)}.
Then A(1) wins after.

Markus Schulze

I am not understanding what you are suggesting.

It sounds like you want to sub-divide the fourth category into these two
sub-categories:

  • A wins before cloning, A(1) wins after cloning, and A(1) wins if only
    the clones participate.

  • A wins before cloning, A(1) wins after cloning, but A(1) does not win
    if only the clones participate.

Do we need to distinguish between these two cases?

It seems to me that any of the clones winning instead of the original
similar candidate is a case of the clone displacing the original candidate.

It looks like he's suggesting a related criterion (call it "independence
of non-clone alternatives") that is failed if A1 wins the ordinary
election (after clones have been added), but A2 wins when everybody but
the clones are eliminated.

That may be a desirable criterion, but if A won before the cloning
happened, I don't think it's a failure of the independence of clones
criterion.

-km

On 02.07.2021 02:32, VoteFair wrote: > On 6/27/2021 11:15 AM, Markus Schulze wrote: >> Hallo, >> >> I recommend the following formulation for the fourth category: >> >> Suppose A won before cloning. >> Suppose A is cloned to A(1),...,A(n). >> Suppose A(1) wins when the used election method is applied only to >> {A(1),...,A(n)}. >> Then A(1) wins after. >> >> Markus Schulze > > I am not understanding what you are suggesting. > > It sounds like you want to sub-divide the fourth category into these two > sub-categories: > > * A wins before cloning, A(1) wins after cloning, and A(1) wins if only > the clones participate. > > * A wins before cloning, A(1) wins after cloning, but A(1) does not win > if only the clones participate. > > Do we need to distinguish between these two cases? > > It seems to me that any of the clones winning instead of the original > similar candidate is a case of the clone displacing the original candidate. It looks like he's suggesting a related criterion (call it "independence of non-clone alternatives") that is failed if A1 wins the ordinary election (after clones have been added), but A2 wins when everybody but the clones are eliminated. That may be a desirable criterion, but if A won before the cloning happened, I don't think it's a failure of the independence of clones criterion. -km