FW: [EM] Responses to some of Forest's ideas

[LAYTON Craig]

Forest wrote:

>Personally, I have little sympathy with these kinds of regrets.

They're fantastic examples.  You make quite a persuasive argument.

>Does anybody have an example in which reasonable strategy would tend to
>make the Approval winner definitely less desirable than the Condorcet
>Winner?

"Reasonable strategy" is a fairly loose term.  In an electorate with very
innacurate polling information, reasonable strategy could result in a pretty
bad outcome.  I can give you an example with zero info strategy;

10 A>B>C>D : 100>30>1>0  Approval vote A
40 B>D>A>C : 100>52>51>0 Approval vote BDA
40 C>B>A>D : 100>95>66>0 Approval vote CBA
10 D>C>B>A : 100>60>50>0 Approval vote DC

A is the Approval winner with 90% approval (compared to 80% for B)
B is the Condorcet, Borda, IRV and Cardinal Ratings winner, based on sincere
ballots.
B is the SU winner over A by 275 (av. 69) to 217 (av. 54).  90% of voters
prefer B to A.

It would be difficult to argue that A is the deserving winner here.

The vague notion that attracts Condorcet advocates (what Rob termed
"stability") is a consistency criterion. The idea being that, with the same
group of voters with the same preferences, and the same field of candidates,
the same candidate should win every time.  This will happen much more often
in Condorcet than in any other method.  Rules should be generally designed
to apply in every situation evenly.  It is arguable that this property is
more important than what outcome the rules actually achieve.

Craig