[EM] The good counter-example

[Blake Cretney]

On Thu, 2002-09-19 at 20:42, Adam Tarr wrote:
> Blake just chimed in with another example, but it has seven or eight 
> factions rather than five, so I'm not going to try to get inside that 
> one.  As an aside, Blake, haven't you said in the past that you would 
> recommend that voters in winning votes methods should randomly complete 
> their ballots it they have no sincere lower preference?  This would seem to 
> be bad advice for the Al supporters above.  Honestly, this argument of 
> yours was one of the reasons I made the claim in the first place; it seemed 
> to logically follow from your argument.  I'd guess your response would be 
> that random completion would not _consistently_ hurt your candidate, even 
> if some of the votes were counter-productive.

Exactly.  But are you saying that you would prefer a method where
partial ranking sometimes hurts, but never helps, the chances for the
ranked candidates?  How is that different from penalizing people for
partial rankings?

But if that's what you want, it seems to be possible to construct a
method that does this, but not one that is consistent with the Condorcet
criterion.  However, if you weaken the Condorcet criterion to say only
that a candidate must win if it gets a majority of the total ballots in
every pairwise comparison (not just a majority of those participating in
that pairwise contest), then it becomes possible.  The method I
mentioned in my previous email passes this weakened Condorcet criterion,
as well as never rewarding truncation. 

---
Blake Cretney
http://condorcet.org


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