Mixed Condorcet-Plurality (fwd)

Forest Simmons fsimmons at pcc.edu
Wed Apr 11 16:07:36 PDT 2001

One thing I forgot to mention. In Smith/Approval (Approval as a Condorcet
completion method) there are various options.

One of these is to use (lack of) Approval to eliminate candidates one by
one until the Smith Set reduces to one candidate.

Another simpler method is to just take the most approved member of the
original Smith Set as the winner.

There are other variations, too.


---------- Forwarded message ----------
Date: Wed, 11 Apr 2001 15:21:52 -0700 (PDT)
From: Forest Simmons <fsimmons at pcc.edu>
Reply-To: election-methods-list at eskimo.com
To: martin at myreddice.co.uk
Cc: election-methods-list at eskimo.com
Subject: Re: Mixed Condorcet-Plurality
Resent-Date: Wed, 11 Apr 2001 15:22:48 -0700
Resent-From: election-methods-list at eskimo.com

On Wed, 11 Apr 2001, Martin Harper wrote:


> I would call your suggestion "Smith//Plurality" - the Smith Set is the smallest
> possible set of candidates such that all members of the Smith Set pairwise beat
> all non-members.
> I *think* it's monotonic, but I'm not sure: Plurality itself is monotonic, as is
> Smith, so it ought to be. On the other hand, it definately isn't immune to
> clones, so there may be issues of vote-splitting. Whether these problems
> manifest themselves often enough to be a concern is less certain. If simplicity
> and transparency is important, then I might prefer this method over the more
> complex Condorcet variants.

Forest says ...

It seems to me that plurality completion encourages insincere voting of
one's compromise above one's favorite in a close race because the first
place counts so much in the cycle breaking method, i.e. if the cycle
breaking method suffers from "spoilage" then so does the

That's why I advocate "Smith/Approval" which simply requires an extra mark
to indicate the Approval cutoff on each ballot. When the mark is omitted,
then the truncation point can be taken as the cutoff.

Remember that Nader's supposed spoilage of Gore's chances is the biggest
impetus to IRV support among North American progressives. How ironic!

Because I put a high premium on the Favorite Betrayal Criterion my main
interests are in studying and promoting Approval and its possible
generalizations or applications. One neglected application is as a
completion method for Condorcet.


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