[EM] A few strategy details

[Michael Ossipoff]

First, I take it back: MJ doesn't meet Woodall's Majority for Solid
Coalitions.

MJ fails Majority for Solid Coalitions, in addition to failing MMC.

Depending on whether you Approval vote, MJ is either expensive Approval or
bad Bucklin.

Comparison of the best methods--CD Approval:

3-Slot ICT, U/P, & TTR MGR meet CD.

3-Slot ICT & TTR MGR have an additional deluxe advantage:

At least with 3 candidates, if a majority faction mistakenly approve the
middle candidate, they don't thereby give away the election. The majority
candidate still wins.

3-Slot ICT is simpler than TTR MGR. Is there a situation that justifies the
extra complexity?

So far, 3-slot ICT looks like the best method.  ...for when people don't
demand or need unlimited ranking, with the attendant loss of CD, & lowering
of Pt (probability of electing from the top-set), for voters not
majority-favored.

Ranking could be needed by seriously overcompromising voters, or by voters
whom rivalry  prevents from equal-ranking close candidates.

Strategy in common:

CWs means sincere CW.

CWse means expected CWs.

Defensive strategy is very similar in Approval, Bucklin, & MAM.

In Approval, as an individual, of course just approve your top-set.

But say it's a 1-dimensional political spectrum & you're not
majority-favored. The CWse is at the bottom end of your top-set.

Hir voters prefer the candidates you like less than hir to those you like
more. Maybe some of them are in those voters' top-set.

You want them to not approve those worse candidates

Maybe an agreement would be collectively desirable, not to vote past the
CWse, even if it means not approving all of our top-set.

A bonus for the CWs' voters is that they elect the best candidate they can.

In Bucklin too, if everyone is ranking, & you aren't majority-favored,
you'd like people to not rank last the CWse.

In MAM, burial is deterred if the CWse's voters plump.

But, in Approval, Bucklin, & MAM,  there's another way you can protect the
CWse: Top-voted hir. In Approval you'd be voting hir equal to your
favorite.

In Plain Bucklin
or MAM,  vote hir alone at top.

(In MAM that prevents a strategic cycle. In Plain Bucklin, it gives hir
your vote before hir voters give it away).

But then you're doubly helping hir against your favorite.

Also, it goes against the reason why one would want rankings ...to rank in
sincere order.

So let's say CWse-protective favorite-burial is out.

Then, if you aren't majority-favored , you're really counting & depending
on other voters to protect the CWse.

...more than in in Approval.

...& your Pt is lower.

This posting is long. I'll stop here for now.

Michael Ossipoff
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