[EM] Is there a PR voting method obeying "participation" criterion?

[Warren Smith]

This seems to be an open question at present.  But it might be pretty
easy to prove or disprove.

A multiwinner voting method "obeys participation" if an extra voter,
by voting honestly, cannot make the election result worse (in her
view) than if she had not voted.
(If you remove a winner and replace it with somebody that voter considers
better, the winner set got better. Any change in the winner set not arising
from a finite sequence of such improvement steps, is a "worsening" in the view
of some voter.)

It is "fair" if symmetric under permuting the candidates and voters.

Conjecture: there does not exist a fair multiwinner proportional representation
voting method obeying participation.


-- 
Warren D. Smith
http://RangeVoting.org  <-- add your endorsement (by clicking
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and
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