[EM] Sports and "The Condorcet Mindset"

[Alex Small]

I know that IRV has been debated ad nauseum, but since a new member raised
the subject it may be worth flogging that dead horse again.

Donald Davison contends that Condorcet and Approval advocates want to help
candidates with no chance of winning.  He's only right to the extent that
we want to see more than 2 competitive options, and plurality voting makes
it impossible for more than 2 parties to remain competitive over time. 
The goal is not to give crutches to lame candidates, but rather to force
complacent duopolists to show their mettle if a new challenger decides to
enter the ring.  So, in that sense, any person who wants a method other
than plurality suffers from Donald's so-called "Condorcet Mindset."

However, Donald's contention seems to be that IRV forces candidates to
compete and excel, while Approval and Condorcet are similar to the Special
Olympics athletes who helped a fallen comrade make it to the finish line. 
I suppose it all depends on what your favorite sport is.

To make imperfect sports analogies, IRV is like a post-season tournament,
where teams and players qualify by doing well during the regular season
and procede through a series of eliminations.  Condorcet is more like
boxing, where a person only keeps the title by being undefeated (cycles
are deadlocks where NO person is undefeated).  Approval Voting is like
gymnastics, where each candidate is judged independently.

Would Donald suggest that the world heavyweight champion is a bad athlete
because he won through one-on-one fights?  Of course not.  Would Donald
suggest that an Olympic gold medalist in gymnastics is a bad athlete
because the judges scored him or her independently of the other
candidates?  Of course not.

So, why would Donald say that the candidate who systematically defeated
every other opponent one-on-one is a weak candidate?  Why would he say
that the candidate who got more yes votes than any other is a weak
candidate?

The fact is that IRV, Approval, and Condorcet all have respectable
criteria from the standpoint of requiring excellence.  IRV forces
candidates to compete for votes all at once, systematically eliminating
candidates until one has sufficient votes.  Approval places the candidates
before the voters one at a time, to be rated on their performance. 
Condorcet forces them to go head-to-head in pairs.

To me, the biggest problem with IRV is the many perverse incentives for
insincerity.  All methods are manipulable, but some are more manipulable
than others.  In non-monotonic situations, where a candidate actually goes
from defeat to victory because some voters ranked him lower, IRV's
emphasis on excellence is perversely undermined.

Also, IRV can be manipulated by the addition of new candidates.  A
candidate can go from defeat to victory when a new candidate is added to
the mix, even though that new candidate failed to win and never could have
defeated the previous winner in direct competition.  By contrast, adding a
new candidate to a Condorcet election only changes the result if the new
guy can defeat the old winner in direct competition, and it never changes
an Approval election unless the new guy himself wins.

So, we aren't looking to race wheelchairs here.  We are looking for
competitions with fewer loopholes that a weak candidate can use to slip
by.

Finally, to make a few more bad sports analogies, Donald Saari's favorite
sport must be synchronized swimming, because it respects symmetry (that's
about the only merit to the Borda count, which really does put lame
candidates on crutches).  Alan Natapoff doesn't give a damn about sports,
he just likes to place bets (and what could be more random and chaotic
than our electoral college?).



Alex


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