[EM] Unranked IRV versus Approval - divergent winners exist!

[MIKE OSSIPOFF]

>Because there IS no best that will be agreed by all.

But presumably there are some methods that seem to _you_ to be better
than others. So why should you advocate less.

Majority rule is not a
>well defined concept with 3 or more choices.

...certainly not by IRVies. There are 2 definitions of majority--the
universal definition, and the IRVie definition.

What does majority mean, no matter how many candidates there are?
More than half of the voters.

What does majority rule mean, no matter how many candidates there are?
A majority getting its way. With nearly all single-winner methods
(but maybe not with Borda), a majority can always get its way.
If it wants to elect someone, that's easy. It also has the power to
ensure that a certain candidate _won't_ win. If we were to just say
that majority rule means a majority getting its way, and not qualify
that, then, no how many or how few candidates there are, majority rule
would be a useless standard, since all methods meet it.

So how about a majority getting its way by sincere voting? That's
something that the majority defensive strategy criteria measure, and
IRV fails all of those criteria. Condorcet's method meets all of them.
Approval meets one of them, WDSC, in addition to the additional
defensive strategy criterion FBC.



Approval and Condorcet are
>not single votes - they are N and N*(N-1)/2 elections which must be merged
>somehow to pick a winner.

It isn't clear why you think that Approval is about N elections.

Mike Ossipoff


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