Talk:Condorcet method/Archive 1

There's a good website on Condorcet's method. I forget the link.

One important point is to mention Arrow's Theorem. There is a weaker verison of Arrow's conditions that the Condorcet method does satisfy.

Probably referring to http://electionmethods.org . There's a redefinition of Independence from Irrelevant Alternatives Criteria whereby "Irrelevant" is redefined. Basically, under the weaker version, candidates locked in a circular tie aren't considered "irrelevant". Condorcet can meet that criteria because it's only the tie-breaker that gets you in trouble, not the core method.

This weaker criterion is called Local Independence of Irrelevant Alternatives.

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Condorcet vs. IRV

On the other hand, the Condorcet winner could be a candidate with very weak core support, raising questions about that winner's legitimacy.

What is this "core support" that the Condorcet winner might lack? This needs to be explained or I'm going delete or majorly rework this comment. -- AdamRaizen 21:01, 2003 Aug 20 (UTC)

I didn't make this comment and I wouldn't make this argument. But I believe the arguments goes something like this: suppose you have preferences as follows:

47% A > B > C
46% C > B > A
4% B > A > C
3% B > C > A

In IRV, it would be clear that very few people actually support B as a real choice, only as a fallback. Therefore, B would be eliminated, and one of the two candidates with "core" (first-place) support would win. Even clearer, we could use a payoff matrix:

    A  B  C
47% 8  2  1
46% 1  2  8
 4% 2  8  1
 3% 1  8  2

DanKeshet 21:11, Aug 20, 2003 (UTC)

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I added some objections to Condorcet being used in "serious" elections. Before I get roasted as a Condorcet basher, let me put in the record that I would love for Condorcet to be the way we vote. But I've been an agent, a poll clerk, and a deputy returning officer in enough elections and watched enough debacle in the US with its blackbox machines to have decided, regretfully, that the Condorcet ideal is very unlikely to be implemented in a way most electors could ever trust. Whether they were stupid/paranoid electors, or thinking electors. As flawed as our (Nova Scotia) methods are, it's very hard to jigger them without someone seeing it. Kwantus (2003 Aug 30)

OK, here is your roasting:

in the procedure. (Even assuming the code is publically available, as in Australia but not in the USA, there is no way to prove to an elector that a results computer has been loaded with that code, nor that the machine is operating correctly even assuming its design is perfect.)

That's an issue independent of the voting system.

Not if the system is so complex as to make mechanical counting tempting. The way we do an election is open at every stage and simple enough no mechanical aid beyond a simple calculator is necessary. I grant that our elections are non-Condorcet ... but I believe elector trust in a nonCondorcet system is better than rampant distrust in a Condorcet system.

The transparency of the complex Australian IRV count is less often questioned than that of the heavily automated USA plurality elections.

You missed the point. The distinction I'm after is that Australia puts the code for its voting machines on a website for public inspection whereas in the USA that code is a trade secret which the public is expressly FORBIDDEN to inspect. The former system certainly engenders more voter faith than the latter; regardless, in neither case can a skeptical elector or even a poll official satisfy himself that the machine is running the proper code.

BTW the use of IRV in Australia refutes your argument, since it seems to be aimed more at the complexity of ranked methods in general than anything particular to Condorcet.

No, again, what it shows is that there's more confidence in the Australian technology than the American -- the American system is pretty blatantly riggable. But the confidence in the Australian system is still misplaced (unless they revert to a paper backup in disputed cases -- i don't know).

Another is division of labour; counting cannot be distributed to the workers in individual polls

I don't see why not.

Because the time to communicate the count to the returning office would be large fraction of or even more than the time it'd take the RO to count the ballots itself. (Unless you use digital methods, which cannot be inspected.)

. In Nova Scotia, a poll usually handles about 400 electors, and in a recent election there were 7 candidates in one riding. That means there 5040 ways of marking a full-ranking ballot. The ballot of every elector in a poll, indeed a dozen polls, could be unique. (Even assuming a few favourite candidates, there's a lot of wiggleroom.) The present method of counting ballots in the poll and telephoning the tallies to the returning office cannot be adapted; the polls in such a riding could easily have dozens of numbers to call in, requiring.

Exactly 49 numbers. Managable by phone I would have thought.

hmm...y'okay, I guess the pairwise counts are enough (tho 49 is still a long list to transfer accurately verbally). But if you want to audit to the number of ballots cast, you then have to insist all ballots are marked with a full ranking else the pairwise counts won't share their total. <suddenly i'm not sure they would even then, i'll have to cipher> (There's nothing deeply wrong about such insistence but there'd be lots of electors who'd mark their ballot in the old way…follow instructions? ha!—and either that can be accomodated…there's a quite reasonable interpretation of a mark-yer-X-type ballot—at the expense of being able to check the pairwise totals against each other, or it can be a lot of rejected ballots.)

<PS: actually i guess you can make that work for only those two kinds of ballots—no trying to handle partial orderings. Otherwise you lose the cross-checking, and converting about 400 7-candidate ballots into 42 or 49 numbers is hairy enough you want the cross-checking.>

--pm67nz