New pairwise tie-breaker (was Re: Various Condorcet Tie Breakers

[Mike Ossipoff]

The suggested modification of Young's method would probably
give the same results as Young's method. Because: If Young
elects the alternative that can beat everything by ignoring the
fewest pairwise preference votes--then ignoring a preference
vote for A over B has the same effect, for getting rid of
a defeat, as changing an A=B ballot to B>A.

A trouble with Young's method is that, though there's a majority
against Dole, and not against anyone else, that doesn't mean
that Clinton beats Dole by a wide margin. That could still be
the narrowest margin, even though it's the biggest vote-against,
and the only majority defeat, and Dole is the only majority-rejected
candidate.

That's a reason why Young can't have Condorcet's
properties or meet the criteria that Condorcet meets.

Even if it's a fairly good size margin for Clinton > Dole,
maybe Dole voters' truncation makes Clinton beaten by a huger
margin, and Dole voters outnumber Nader voters well enough
that (majority-rejected) Dole's marging of defeat, though
not small, is still the smallest.

The LO2E criteria & the IME criterion depend on GMC. To meet
those criteria, a method mustn't elect a candidate with a
majority against him unless everyone has a majority against him.


Mike


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