[EM] Condorcet cyclic drop rule

[MIKE OSSIPOFF]

Craig wrote:

It is worth noting, too, that defeat support is more likely to
>punish a voter for truncating a vote.

It doesn't punish the voter for truncating. It merely doesn't reward
him by letting him thereby steal the election from a sincere CW.

But I assure you that, no matter what the method is, refusal to support
a needed compromise will worsen the outcome for you. Every voting system
punishes truncation, except for Plurality, which has no truncation,
because you're only allowed to vote for 1. But even with Plurality
you can regret not helping a needed compromise.

>For some time I thought this was an
>advantage of defeat support (in that it encourages full rankings, and
>therefore political participation), but I no longer believe that this is 
>the
>case.

The purpose of Condorcet's SFC property isn't to encourage people
to not truncate because they won't thereby steal the election from
a sincere CW. A way that Condorcet encourages sincere voting is:

If no one falsifies a preference, and if a majority of the voters
prefer the sincere CW to Jones, and if they vote sincerely, then
Jones won't win. Guaranteed.

That means that the members of that majority are free to vote sincerely,
and needn't worry about strategy.

More generally:

If no one falsifies a preference, and Smith, a member of the sincere
Smith set, is preferred to Jones by a majority, and if no one
falsifies a preference, and if Jones isn't in the sincere Smith set,
then the members of that majority can ensure that Jones won't win
merely by voting sincerely. They don't need strategy.

Those are SFC & GSFC. Under plausible conditions, that majority
doesn't need strategy in Condorcet, and has no strategic need to
strategize. Why don't you consider that an advantage?

Mike Ossipoff


>

_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com