[Election-Methods] When Voters Strategize, Approval Voting Elects Condorcet Winners but Condorcet Methods can Elect Condorcet Losers

[Abd ul-Rahman Lomax]

At 02:56 PM 8/5/2007, Peter Barath wrote:
> From your words I guess you propose a real runoff in a later
>time, when the results of the first round are already known.
>
>Is this real and principal decision, or only practical?
>Would it be possible either in Range or in Approval to
>gain this pairwise comparison information from the
>already cast votes? Maybe by Condorcet-style votes
>or something? (People don't like to vote twice.)

Of course they don't. However, if you choose the pairwise winner, you 
might as well use a Condorcet method, but you'll lose the 
optimization of overall satisfaction. And if you choose the Range 
winner, you are failing to respect the principle of majority consent. 
Unless you make the consent explicit.

That's possible. However, voters, when they consent, would not know 
exactly what they were consenting to. It's problematic.

When you realize that runoffs would be relatively rare -- the Range 
winner is usually also the pairwise winner -- and if the office being 
filled by the election is important, then the inconvenience of a 
runoff is minor compared to the value.

Plus the trouble it is to vote again is actually a test of the 
preference strengths expressed in the Range election.

To understand this, consider the scenario that there *is* a pairwise 
winner who is beaten in the Range vote. It must be that more people 
preferred one over the Range winner, but only weakly.

If they were accurate in expressing this, they don't need to bother 
voting in the runoff! They actually will get a good result (not 
necessarily the best, from their point of view, but good) by staying home.

Whereas the Range winner, in this context, was supported by people 
with stronger preferences. Okay, prove it by showing up to vote!

It's quite fair! But it also will detect errors in the process.

>The second question:
>
>As far as we understand, Steven Brams and Peter Fishburn can be
>considered as foundig fathers of proposing Approval vote
>in modern days (Wikipedia - Voting system says it was in use
>in Venice in the 13th century!).
>
>Who can be honoured as proposer of Approval+2 and Range+2?
>Do they have the same origin?

No. Range+2 was tested by Warren, but his +2, I believe, was a runoff 
between the top two Range winners. As to pairing off the Range winner 
and preference winner, that is, I believe, my own suggestion, I did 
not see it anywhere else. I then suggested that the same idea could 
be applied to Approval, and as part of this, even if there is no 
preference indicator in the Range election, holding a runoff under 
some circumstances made sense to me, so I suggested it. Again, I 
didn't see this anywhere.

However, I came to this idea partly by seeing that Approval was being 
proposed in a place which already had a top two runoff for Plurality, 
when no candidate gained a majority. So it was simply a matter of 
extending existing practice into the new method.

It gets better, I think, if there *is* preference indication in 
Approval or other low resolution Range methods, because then we have 
a clear indication of true, not forced, majority acceptance of a winner.

In pure deliberative process, whatever process is used for election, 
the result must be accepted by a majority before it is final. 
Democracy is work. It is not free.

>Peter Barath
>P.S.:
>For your interest: Mensa Hungary uses plurality to elect
>its leaders. Mensa International uses instant runoff for
>the same aim.

IRV is an idea which looks pretty good until one starts looking 
closely and considering alternatives. Once you are using a full 
ranked ballot, you might as well go in one of two directions: ranked 
methods, which would presumably be Condorcet compliant (always 
electing a pairwise winner if one exists), or range methods, which 
are more likely to choose someone who will be maximally acceptable, 
even if not the first preference of most.

But Mensa really should look at the whole concept of democratic 
structure. It's possible to have a large-scale democracy *without* 
elections at all. See http://beyondpolitics.org/wiki.

And this is an idea which could actually change the world, gently but rapidly.