[EM] Ranking unacceptable candidates.

Michael Ossipoff email9648742 at gmail.com
Thu Oct 17 18:10:08 PDT 2013

 That's strategically safe in IRV, because of IRV's Later-No-Harm compliance.

But, with most rank methods, including Benham and Woodall, it would be
a strategically-bad idea, because it could increase the probability of
electing an unaccetable.

You might say that, if you don't know which unacceptables are more
iikely to win as CW, then it's harmless to rank them. But, if you
think some unacceptables are worse than others, and if others are at
all likely to tend to share your preferences among them, then when
you're ranking U1 over U2, you're voting against a defeat of the one
(U1) who is more ilkely than the other U2) to win as CW. If there's a
tendency for that to be so, for the unacceptable candidate-pairs in
your ranking, then you're increasing the pobability that an
unacceptable will win--as compared to if you didn't rank any

I guess that problem could be fixed by adding a count-rule saying
that, for any candidate you rank below your "unaceptable" mark,
ranking U1 over U2 shall not be counted toward keeping U2 from
pair-beating U1. But it is counted in determining if U1 pair-beat U2.

If I refer to that again, I'll call it "harmless ranking". I only
suggest it for candidates whom you rank below your "unacceptable"

Symmetrical ICT used "power truncation", whereby not ranking X  and Y
counts toward making X beat Y, and toward making Y beat X. SICT was
intended to be Appoval-like, for current-conditions, but maybe power
truncation wouldn't be desirable for Benham and Woodall.

But harmless-ranking might be a good idea, for methods that don't meet
Later-No-Harm. Especially if it's known that some people will insist
on ranking candidates who are unacceptable to them.

But it would also be fine to, instead, just warn voters that it's
better to not rank unacceptable candidates if you feel that your
higher-ranked ones are likely to be more popular with others, as they
might well be, if other voters are anything like you.

I like the expressiveness of he balloting system suggested by Juho, in
which a voter can indicate a point above which candidates are
"Favorites" (even if they aren't all top-ranked, and a point below
which candidate are "Unacceptable", and a point below which candidates
are "Entirely, Abominably, Unaccepable".

Since that would, without question, encourage people to rank
candidates they consider unacceptable, then it should be accompanied
by, at least, harmless-ranking.

Michael Ossipoff

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