Condorcet is in the business of finding the best liked candidate, just as Plurality is.
Often one candidate is truly much the best liked, Plurality will have no problem, and Condorcet will agree since most voters will rank that candidate as their first choice.
Toward the other extreme, three candidates can be about equally best liked, Plurality may declare any of them the winner (near a tie) and the voters can make life hard for the vote counters by not ranking a single best liked candidate:
A preferred over each other candidate except B
B preferred over each other candidate except C
C preferred over each other candidate except A
Here we say the top candidates in such an election form a cycle - each is liked better than the others by many voters and each candidate outside the cycle is liked less than any cycle member. Now if A is liked much better than B and C liked much better than A, while B is only liked a bit more than C, we ignore B>C and declare C the winner.
MAJOR point is that all the members of the cycle got there by nearly equal backing by voters and, while we must pick a winner, it is most important that we have a rule that picks from the cycle members, while different counters might write different rules.
There could be more than three candidates in a cycle - IF - voters choose such ranking. This does not change the concept.
Likewise, IRV can suffer spoilers, a problem Condorcet avoids by reading all the ranking in each ballot.
==========================
For example: 3 ABC 4 BCA 5 CAB
counts as: 8 A>B, 4 B>A 7 B>C, 5 C>B 9 C>A, 3 A>C
Here we gave a cycle of A/B/C with 9 of 12 voters agreeing C is better than A, and C winning under Condorcet.
Also, with permitted truncation for IRV or Condorcet: 6 A 5 CB 4 B
Condorcet will see that C is not liked enough to win, and 9 B wins over 6 A. IRV would discard the 4 B, and the 6 A would win, for IRV would not notice the 9 B represents stronger liking by a majority (even though 5 of them liked C better).
On Wed, 13 Oct 2004 14:42:14 +0000 MIKE OSSIPOFF wrote:
Someone wrote:
However, the lack of any real world implementations to point to, and the difficulty of explaining the tie-breaker make it very difficult to explain to voters.
I reply:
How difficult is it to explain this:
If no one is initially unbeaten, drop the weakest defeat. Repeat till someone is unbeaten.
[end of PC definition]
Or:
If no one is unbeaten, drop the weakest defeat that's in a cycle. Repeat till someone is unbeaten.
[end of SD definition]
Mike Ossipoff
-- [EMAIL PROTECTED] people.clarityconnect.com/webpages3/davek Dave Ketchum 108 Halstead Ave, Owego, NY 13827-1708 607-687-5026 Do to no one what you would not want done to you. If you want peace, work for justice.
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