[EM] More thoughts on approval margins

[Monkey Puzzle]

I think I'm getting the sieve idea into better focus now.  Is the
following method is equivalent to Approval Sorted Margins?

Ranked ballots with approval cutoff.

Strong defeat = pairwise defeat by higher-approved candidate

Strong losers = set of all strongly defeated candidates

Provisional set = set of non-strongly-defeated candidates
   Each provisional winner defeats all higher-approved members of the set.
   This is Forest's "P" set.  Convenient that Provisional starts with
P, isn't it? ;-)

Marginal defeat:  Pairwise defeat of provisional candidate X by strong
loser Y under these conditions:
    (1)    Z = the least-approved provisional winner who strongly defeats Y.
     (2)   Approval(X) - Approval(Y) < Approval(Z) - Approval(X)
     TODO:  Need a more succinct description of this.

Marginal losers = set of all marginally defeated candidates

Strong set = set of candidates neither strongly nor marginally defeated.

The least-approved member of the strong set defeats all
higher-approved strong candidates and wins the election.

The approval winner and the highest-approved member of the Smith set
are always strong candidates.

I think a good name for this method would be Marginal Ranked Approval
Voting (MRAV).

I've created a page for it here:
   http://wiki.electorama.com/wiki/Marginal_Ranked_Approval_Voting 

One interpretation of the marginal defeat is that a marginal loser
doesn't have enough approval "buoyancy" to rise above the
strong-defeated candidates, and is peeled off of the edge of the
provisional set.

Strategy should be similar to Approval Margins and identical in
3-candidate cases.

The MRAV strong set could be used for a DFC-like random ballot method.

Suggestions?  Discussion?
-- 
araucaria dot araucana at gmail dot com