[EM] Re: Chris: Approval vs IRV

[Chris Benham]

Mike,
I  had written:

One of my fundamental standards is that a method should perform reasonably 
when all the voters vote sincerely (taking no account of how any other voters might vote).

To which you replied:

>IRV fails your standard in the most flagrant and ridiculous ways. This has 
>been very well-described on EM, even in recent weeks, and so don't ask me to 
>repeat the examples. Aside from the recently-posted example, there's also 
>the absurd nonmonotonicity of IRV, even when people vote sincerely.
>
>Actually, IRV is at its very worst when people vote sincerely. Often the CW 
>can be saved only be the extreme insincere strategy of favorite-burial.

CB: At least IRV has some appearance of TRYING to meet this standard.
"Electing the CW" is far from the only interpretation  of "performing reasonably". As Marcus S.
has explained to you before: "The aim of IRV is not to elect the sincere Condorcet winner. The 
aim of IRV is to elect the sincere IRV winner." 

I had continued:
A method should be able to cope with insincerity, but to perform reasonably it definitely shouldn't
DEPEND on insincerity.

You replied:

>Like when, in IRV, the election of a CW depends on voters insincerely voting 
>the CW in 1st place, over their genuine favorite?

CB: In Australia and doubtless many other countries, almost none of the voters have a concept of the
"CW", let alone worry about how they are going to strategise to elect that candidate. So what concepts
do they have? They have the concept that political parties that win single-seat elections are those
that get lots of votes, including lots of first-preference ("primary") votes. They have the concept
that the winner definitely should never be the Majority Loser. They have the concept that votes for
losing  candidates should not be avoidably completely "wasted". They have a concept that elections
are not purely about who wins, but also about things like identity, self-expression, political 
principles and  (sometimes class-based)party-loyalty. Very few voters in Australia are remotely
interested in strategising, and in (at least)some countries that even use Plurality, surprisingly
few are.
So instead of "elect the CW", and apart from (the admittedly somewhat circular) "elect the sincere
IRV winner", what do I mean by "perform reasonably"? The method chooses the winner in a (somewhat)
intuitive and orderly manner,without appearing to "waste" more than half the votes, and thus picks
a winner which is widely accepted (by the supporters of the losing candidates) as "legitimate".

There are many quite intelligent and thoughtful voters in Australia, to whom it has never occured
that there might be any better single-winner election method. They have failed to notice IRV's
"absurd non-monotonicity", and they have no concept of the "CW". They have heard of, and recoil
in horror at Plurality ("First-past-the-post"). They would laugh at Approval.

I think in many countries, even the US, voters and political parties would hate approval. If I
were to be persuaded to drop my Clone Independence standard and take a limited-slot method seriously,
I would go for one of Kevin Venzke's 3-slot methods, like "Withdrawable Approval".
As it is, I think most promising-looking for public political elections is probably something from
the "automated approval" family (which uses ranked ballots).

Chris Benham