[EM] Condorcet vs Approval

[LAYTON Craig]

Joe wrote (in relation to Forest's Condorcet//Approval compromise):

>I like it - was considering the same thing myself (Smith//Approval, I 
>guess it'd be called). If there's only strategy in Condorcet methods if 
>there's a tie, then it'd make sense to resolve the tie using methods 
>which have sincere strategies, rather than ones which could encourage 
>insincerity...

I also think it is good.  My only concern is the complexity of the
instructions, and the requirement to truncate your vote.  I can imagine a
great deal of outrage from voters who look forward to the oppourtunity to
put a particular party last at an election, even to the point of caring more
about this than who they put first.  This isn't a slight on the system - I
think it's great, but it would require an intensive public education scheme.

>Strategy would seem to be quite complex for deciding where to draw the 
>line, though... You're looking at the probability, given that there's a 
>first place tie in approval ratings amongst the members of the Smith Set 
>(which necessarilly means that there's a Condorcet Cycle), that said tie 
>is between I and J.

I think that it's an advantage that the strategy is complex - there would be
few voters who would use strategy, and the approval line would be closer to
strategy-free (zero info) approval.

I've been thinking about insincerity and reversing preferences in voting,
and I've come to the conclusion that it isn't a relevant consideration in
itself.  Why isn't plurality a good system?  With accurate polling
information and strategic voters, the consensus (Approval winner and/or
Condorcet winner and/or utility maximising candidate) should win.  If this
was the case, it wouldn't really matter if people had to reverse
preferences.  But, it isn't the case, because many people use strategy and
many people do not.  There are two obvious solutions - encourage almost all
voters to use strategy, or almost none.  This is the basic divide between
Approval (which tries to do the former) and Condorcet (which tries to do the
latter).  Without proper information on voter behaviour, it is difficult to
predict which will be more successful, but I have maintained that Condorcet
is more likely to be.  As a few of you have pointed out, Condorcet does have
some additional disadvantages vis a vis Approval, particularly the possible
election of a low utility or unknown Condorcet winner.  A compromise method
might be the answer, if its complexity wasn't a problem.