[EM] Truncation

[Elisabeth Varin/Stephane Rouillon]

The methods J and K described (maybe not in a very good way)
under the electoral_systems_designers single winner contest as

J)Ranked pairs using relative margins, sequential dropping and
residual approval weights
http://groups.yahoo.com/group/Electoral_systems_designers/message/77
(Stephane Rouillon)

 K)Alternative Vote (or IRV) using residual approval weights
http://groups.yahoo.com/group/Electoral_systems_designers/message/73
(Stephane Rouillon)

could both make the difference beetween the "respected (if
unglamorous) compromise middle" and the "hated (yet still) compromise
middle". The consequence is both extremes would agree on the respected
compromise candidate and take each there chance if it is a hated
compromise candidate. So a voter can rank disliked candidate
without approving any of them.

The idea is to distinguish from your ballot (using Demorep1's ballot)
between your actual preferred candidate and the last eliminated candidate
you would accept to approve. The elimination order is different for each
method (IRV or Condorcet (wv) or Condorcet (rm)).
They are not strategy-free, but from a voter point of view,
it feels like you can have an impact fitting your exact preference order
and approval limit...

Many other systems could be generalized this way I think.
And it allows the possibility to view a Condorcet final ranking
as an elimination process just like IRV...
Eliminating the last from the Condorcet ranking should not affect the
overall Condorcet ranking...

Steph.

Forest Simmons a écrit :

> On Wed, 18 Sep 2002, Adam Tarr wrote in part:
>
> > [Bart wrote in part]
> > >  But then I don't see truncation as necessarily a bad thing. If
> > > truncation can defeat a "hated middle" candidate, it addresses my main
> > > misgiving about the Condorcet methods.
> >
> > Much in the same way that we can't differentiate between the indifferent
> > voter and the lazy voter, we cannot distinguish between the "respected (if
> > unglamorous) compromise middle" and the "hated (yet still) compromise
> > middle".  Smart CBA voters in an approval election will still approve B, to
> > defeat A, anyway.  What method would actually prevent B from winning when
> > the voters act in a logical manner?  Even plurality and IRV encourage CBA
> > voters to dump C for B if they have perfect information.
> >
>
> Relative to the "hated compromise."
>
> In a zero information election Approval would give a better result.
>
> In a perfect information election Approval would pick the CW.
>
> So in a partial information election (somewhere in between the above two
> cases) why would we expect Condorcet to give a result so superior as to
> justify the added complexity of the method?
>
> Forest
>
> ----
> For more information about this list (subscribe, unsubscribe, FAQ, etc),
> please see http://www.eskimo.com/~robla/em

----
For more information about this list (subscribe, unsubscribe, FAQ, etc), 
please see http://www.eskimo.com/~robla/em