[EM] Clarification of AERLO & Strong FBC

[MIKE OSSIPOFF]

Sorry, I was in a hurry when I wrote my most recent reply about that.

Say the method is ERBucklin(whole), with AERLO, and you rank X in 1st place, 
and Y in 2nd place.  And say you make your automatic equal ranking line 
somewhere below Y.

That ballot votes X over Y by the definitions of that term that have been 
posted here. And that ballot votes X over Y in the meaningful sense of the 
term: If it turns out to be between X & Y, and if it's close enough, then 
your ballot (especially combined with another X>Y ballot) could change the 
winner from Y to X.

If no one above your AERLO line wins, then Y and everyone else above that 
line are automatically promoted to 1st place, with X. But that doesn't 
change the fact that you're meaningfully voting X over Y.

So, the that ballot's voter isn't ranking voting anyone equal to hir 
favorite.  Strong FBC isn't violated by the fact that AERLO could promote Y 
to 1st place if needed.

So the answers to question 2 are:

Butcklin needs equal ranking because it doesn't meet Strong FBC. But with 
equal rankings, and with AERLO added, the resulting method meets Strong FBC 
(unless I've overlooked something, of course).

The voter doesn't need to rank anyone equal to his favorite, in the sense 
that, for any outcome (outcome 1) that s/he could get by doing that, there's 
an outcome to which that voter doesn't prefer outcome 1. In other words, an 
outcome just as good as outcome 1, as judged by that voter.

I use the word "prefer", because we've discussed its meaning here.

AERLO might rank someone equal the that voter's favorite, but the voter 
needn't do so. If that sounds like a mere evasion, then I repeat that the 
voter who voted the ballot described above has voted X over Y in the most 
accepted, meaningful sense of the term.

Mike Ossipoff

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