Difference between revisions of "FBPPAR"

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The following system is called FBPPAR voting, for "Favorite-Betrayal-Proof Prefer Accept Reject". It is a version of [[PAR voting]], with an extra "stand aside" option in order to pass the [[favorite betrayal criterion]] (FBC).
 
The following system is called FBPPAR voting, for "Favorite-Betrayal-Proof Prefer Accept Reject". It is a version of [[PAR voting]], with an extra "stand aside" option in order to pass the [[favorite betrayal criterion]] (FBC).
  
# Voters can Prefer, Accept, or Reject each candidate. Default is "Reject" for voters who do not explicitly reject any candidates, and "Accept" otherwise.
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Here's the procedure. Note that the two steps with extra indentation (1.1 and 3.1) only rarely matter, so it's best to understand the system without them first.
## For any preferred candidate, voters may also check "stand aside". (This is rarely useful; it is only worthwhile if they think that the candidate might become the leader in step 3 and stand in the way of a stronger compromise leader.)
 
# Candidates get 1 point for every ballot that prefers them.
 
# Candidates with over 25% Prefer, and less than 50% Reject, are called viable. If there are any candidates who would still be viable if all "prefer/stand aside" votes were counted as "reject", the one of those with the most preferences is designated the leader.
 
# Viable candidates get 1 point for every ballot that accepts them and does not prefer the leader.
 
# Winner is the highest score.
 
  
This is largely a theoretical proposal. In real-world elections, the "compromise" option would probably never be useful.  
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# '''Voters Prefer, Accept, or Reject each candidate.''' On ballots which don't explicitly use "Reject", blanks count as "Reject"; otherwise, blanks count as "Accept".
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## For candidates a voter prefers, they may also mark a "stand aside" option. This has no effect when combined with "accept" or "reject". It is useful for those rare cases when you prefer a candidate, and think they would be the leader in step 2, but do not think they can actually win; so that you think you'd be better off if voters like you compromise more.
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# '''Candidates with at least 25% Prefer, and no more than 50% reject, are "viable"'''. The most-preferred viable candidate (if any) is the leader.
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## When designating the leader (including who counts as "viable" for that purpose only), all "prefer/stand aside" votes count as if they were "reject".
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# Each "prefer" is worth 1 point. For viable candidates, each "accept" on a ballot which doesn't prefer the leader is also worth 1 point. '''Most points wins.'''
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This is largely a theoretical proposal. In real-world elections, the "stand aside" option would probably almost never be useful enough to justify the extra complexity.
  
 
For instance, consider the voting scenarios which meet the following restrictions:
 
For instance, consider the voting scenarios which meet the following restrictions:

Latest revision as of 12:07, 13 November 2016

The following system is called FBPPAR voting, for "Favorite-Betrayal-Proof Prefer Accept Reject". It is a version of PAR voting, with an extra "stand aside" option in order to pass the favorite betrayal criterion (FBC).

Here's the procedure. Note that the two steps with extra indentation (1.1 and 3.1) only rarely matter, so it's best to understand the system without them first.

  1. Voters Prefer, Accept, or Reject each candidate. On ballots which don't explicitly use "Reject", blanks count as "Reject"; otherwise, blanks count as "Accept".
    1. For candidates a voter prefers, they may also mark a "stand aside" option. This has no effect when combined with "accept" or "reject". It is useful for those rare cases when you prefer a candidate, and think they would be the leader in step 2, but do not think they can actually win; so that you think you'd be better off if voters like you compromise more.
  2. Candidates with at least 25% Prefer, and no more than 50% reject, are "viable". The most-preferred viable candidate (if any) is the leader.
    1. When designating the leader (including who counts as "viable" for that purpose only), all "prefer/stand aside" votes count as if they were "reject".
  3. Each "prefer" is worth 1 point. For viable candidates, each "accept" on a ballot which doesn't prefer the leader is also worth 1 point. Most points wins.

This is largely a theoretical proposal. In real-world elections, the "stand aside" option would probably almost never be useful enough to justify the extra complexity.

For instance, consider the voting scenarios which meet the following restrictions:

  1. Each candidate either comes from one of no more than 3 "ideological categories", or is "nonviable".
  2. No "nonviable" candidate is preferred by more than 25%.
  3. Each voter rejects at least one of the 3 "ideological categories" (that is, rejects all candidates in that category), and accepts or prefers all candidates in some other category.
  4. No honest Condorcet cycles.

If the above restrictions hold, then the "compromise" option would never be strategically favored, and so simple PAR voting would meet FBC. It is arguably likely that real-world voting scenarios will meet the above restrictions, except for a negligible fraction of "ideologically atypical" voters. Thus, as a real-world proposal, PAR voting's greater simplicity makes it better than FBPPAR.