[EM] Three suggestions for rank methods and options

[MIKE OSSIPOFF]

1. AERLO:

I proposed this some time ago, but I’d like to mention it again:

It’s an option to be added to a rank method:

Automatic Equal Ranking Line Option (AERLO):

The voter may specify an AERLO line in hir ranking, indicating that if, in the first count, no candidate above that AERLO line wins, then all of those above-line candidates are to be moved to equal top ranking, for the second count.

So, the first count uses the rankings as-is. For the 2nd count, for each ballot for which no above-line candidates won in the 1st count, that ballot moves its above-line candidates up to equal-top.

[end of AERLO definition]

AERLO makes it safe to sincerely rank one’s favorites, or one’s acceptable candidates in a u/a election, instead of starting with them all ranked equal-top. 

Of course, often, promising proposals turn out to have some sort of problem (sometimes an FBC violation), and turn out to be too good to be true. AERLO sounds too good to be true, but I haven’t noticed a problem with AERLO. But of course this proposal is tentative.

It's been said that MMPO is vulnerable to burying, but a majority's mutually top-ranked candidates are safe from burying. AERLO brings that protection even when sincerely
ranking one's favorite or acceptable candidates.

MMPO and MMABucklin (defined below) are among the rank methods that could benefit from AERLO.

2. MMABucklin:

Bucklin is a sort of stepwise Approval, a ranking generalization of MTA. Might it not benefit from the mutuality requirement of MMT and GMAT? Or MTAOC?

So far, this is just a suggestion, and not necessarily a finished proposal.

Mutual-Majority-Approval-Bucklin (MMABucklin):

ABucklin is another name for the ER-Bucklin defined in the electowiki.

MMABucklin is ABucklin, except that for the purpose of finding a majority win, mutual majority sets are looked for.

A 1st choice vote that a ballot gives to a candidate corresponds to a top-rating in MMT. Any other vote that a ballot has given
to a candidate (as of the completion of any particular vote-assignment round) is counted as a "middle" or "coalition-accept" rating. 
As with MMT, top ratings and middle ratings are counted as "above-bottom". A mutual majority set is defined as in MMT's
definition.

As soon as, after a  round of vote-assignments, one or more mutual majority sets (as defined for MMT) are found, the winner is the most
top-rated candidate who is in a mutual majority set. 

[end of MMABucklin definition]

MMABucklin, like ABucklin and MMPO, could benefit from AERLO.

3. In principle, MMT or GMAT, or MMT and MMABucklin with AERLO, could be offered as voting options in an Approval election:

Since MMT, GMAT and MMABucklin  are all closely related to Approval, they seem compatible as voting options in an Approval election, as do MMT
and MMABucklin offered together as options in an Approval election. 

When offering MMABucklin and MMT together as options in an Approval election, wait till MMABucklin finds one or more mutual majority sets (or fails to) before looking for the
most top-rated candidate who is in a mutual majority set. 

For that candidate to beat the Approval winner, s/he would have to:

(I don't know which would be better)

1. have more top ratings than the Approval winner has approvals.

...or 

2. be in a mutual majority set that has more mutual above-bottom ratings than the Approval winner has approvals. Then,
the winner would be the most top-rated candidate in a mutual majority set that has more mutual above-bottom ratings than the Approval winner has
approvals. If there's no such mutual majority set, then the Approval winner wins.

I don't know whether #1 or #2 would be better. Maybe #2 is a better match with Approval.

Mike Ossipoff



 		 	   		  
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