[EM] full ranks in MDDA (not)

[Warren Smith]

Ossipoff made the good point that me objecting to MDDA or ICA bad behavior
(i.e. that ties can be common) if all votes are full rankong
- was a silly objection by me because
1. just rank all but last candidate (then last not "approved" then approval counts not tied)
2. if this really were to happen then voters would have strategic incentive to break ties
by ranking only 1 or a subset.

These are good points but
A. I would prefer it if MDDA actually forbids approving everybody e.g. by saying
"if you rank them all, then the last is automatically disapproved."  Then we are
sure and do not have to depend on this assumption.
B. If last-not-approved-only behavior is very common then the result will be
"AntiPlurality voting" to do the approvals.  AntiPlurality voting is a very bad system
in which with strategy a "dark horse" always wins.  So this gives me bad vibes.
Seem to me this might happen in a substantial subclass of elections - then things
could still be bad, albeit in a different way.
C. Point (2) impresses me the most.
But I still feel unhappy about the whole idea (which I think Rob L is also
unhappy about) that in these systems voters (i) have incentive to truncate their
ballots (ii) have incentive not to, and they have to tradeoff these two strategic
incentives.  It would be better if voter always has incentive to give more
info.  I mean, for all we currently seem to know, it might even be that the
best voter strategy in these sysems is actually just to plurality-vote,
in which case these systems might act just like the plurality system with
strategic voters - just like now! - which is not so wonderful.  I am not saying this
is true, but I am saying it isn't currently clearly extremely not true.

wds