[EM] Fwd: Is Condorcet The Turkey?

[Kevin Venzke]

> Hello List
> 
> Recently there have been a large number of postings regarding something 
> called the turkey problem- indifferent/poor candidates winning as the least worst 
> choice in a condorcet ballet.

Yes, but I think we all still like Condorcet.

> Due to the nature of the Condorcet method- which considers lower preferences 
> before the fate of higher preferences is decided- condorcet would appear to me 
> to be a turkey electoral system.

How about "system with potential to elect turkeys."

> The fundamental difference as regards the results between condorcet and 
> irving is that  condorcet allows the election of candidates of candidates with 
> little or no first or higher preference support. It is these candidates who are 
> likely to be the turkeys.

Yes, but IRV is an extreme solution to this.  Plurality would plug the hole,
too.  There are plenty of ways to address Condorcet's turkey problem, if
it is perceived to be a problem: "None of the Below" option, approval cutoff
and threshold, limited ranks (e.g., with three ranks, it is guaranteed that a
CW was at least ranked in the middle by some people), count first-place
rankings (or those above an approval divider) as double opposition in the 
pairwise matrix...

> Candidate C does nothing, says nothing and offends nobody.

If C is basically invisible, I don't think the number of people voting
C>Worst will match the number of people voting "Worst is best."

> It occurs to me that the best way to win a single seat condorcet election is 
> to stand on a platform of bland, vague and generalised policies that nobody 
> could disagree with or be offended by.
> 
> Politics is fundamentally about disagreement, about different people 
> supporting positions and policies that are different to each other and often in 
> opposition to each other. Compromise and consensus are good things but not at any 
> cost.Condorcet appears as a ' compromise at any cost' electoral system. It will 
> elect candidates whose only merit is that they offend no-one.

In other words, campaigns become about personality instead of policy.  I
don't think that's necessarily a bad thing.  Whatever policies the elected
representatives enact, they still need to get reelected.

I think "compromise at any cost" is a good strategy for electing the members
of a legislature.  Policies supported by a majority vote of compromises should
be pretty reasonable.  But if you elect lop-sided candidates, chances are you
will get lop-sided results.  That is what I want to avoid "at any cost," and
compromise at the election level appears to be the solution.

> Irving also elects compromise candidates, however under irving a candidate 
> must get a reasonable proportion of first/higher preference support to reach 
> next stage of the election and win. A candidate cannot win by being everybody's 
> last preference.

If IRV elects "compromise" candidates, then so does Plurality.  They both
elect candidates from the big, entrenched parties.  It's very hard for an
independent to win, even if a majority actually likes him best.

Regarding your last sentence, of course that can't happen in Condorcet,
either.

> Compromise candidates who attract a reasonable level of higher preference 
> support are probably good people to elect. They have said or done something to 
> make people positively support them. Compromise candidates who attract little or 
> no higher preference support, who have said and done nothing and whose sole 
> merit is that they offend and upset nobody are probably not good people to 
> elect.
> 
> Irving elects the first type of compromise candidate but not the second, 
> condorcet elects both. This is why irving is better than condorcet.

I do not believe IRV elects the first type, either, unless you think the
major two parties' candidates actually count as "compromise candidates."

Now I will offer reasons why Condorcet is better than IRV.
1. You can generally vote sincerely.  In IRV, you have to keep in mind
that you cannot support a candidate after he's been eliminated.
2. Condorcet elects candidates who pairwise are preferred to every other
candidate.  That's what a legislature would do.  Imagine if a legislature
used IRV: "No, it doesn't matter how many people want to support X now.
X didn't have first-place support, so it's eliminated."
3. A candidate can win even if he isn't believed to be viable.  This has
to do with the "manipulation by bad info" topic that Forest brought up.

Actually, let me give an example of that.  Say there are three candidates
in an IRV election: the entrenched Left, the entrenched Right, and some
popular Independent.  Even if you like the Independent the best, it is
possible that ranking him #1 will cause your second-choice to be eliminated
first.  You have no guarantee that supporters of your second choice
want to transfer their votes to Independent.  Thus by ranking Independent
first, you could cause your least favorite to win.  So there is incentive
to up-rank your preferred entrenched candidate, because it is risky
to put Independent first.


IRV would be somewhat better if you could support multiple candidates at
the same time.  That would take some of the guessing out of it.


Kevin Venzke
stepjak at yahoo.fr


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