Re: Range Voting - the simpler better alternative to Condorcet voting

[Ian Jackson <ian@davenant.greenend.org.uk>]

Barak A. Pearlmutter writes ("Re: Range Voting - the simpler better alternative to Condorcet voting"):
> So (aside from calling me names) it seems like your argument boils
> down to the idea that somehow Range Voting causes voters to be less
> honest than they are with Condorcet?  [...]

Your fundamental fallacy is that you treat `the voters' as a unified
entity - which they are not.  In particular, the situation you fail to
cover in your `exhaustive' list is the one where _some_ of the voters
vote tactically[1]; in that situation tactical voters do better than
non-tactical ones.  That is unfair and perverse.

The difficulty that Steve is pointing out is that one cannot give
honest and straightforward instructions to the voter.  Specifically,
the instructions to the voter must either
 - describe how they should best vote tactically depending on
   the various situations that the voter thinks are likely to
   arise (ie, be tactically complex)
or
 - give advice which is not in the best interests of the voter
   to which it is addressed (ie, be actively dishonest)
or
 - fail to usefully convey to the voter what the likely effect of
   their vote is (ie, be dishonest by omission)

Condorcet (and indeed conventional STV) do not suffer from this
problem and this fact is one of their chief advantages.  It's a
special case of the general property of being `gaming-resistant' - ie,
we want the game implied by the voting system to be one where the most
effective strategies are the ones which are the ones we want the
players to adopt.

With range voting, each individual voter's interests are best served
if they only use the extremes of the scoring range.  The only respect
in which this is different from approval voting is that the naive
voter is given the false impression that they might usefully give some
candidates middling scores.  So approval voting is strictly superior
to range voting - why aren't you plugging it ?

Ian.

[1] Voting tactically is what you call `dishonestly' but I don't agree
    with that value judgement.  A voter is not dishonest when they
    vote tactically; they're merely playing the game as it has been
    set up so as best to achieve their aims - which are often as much
    to do with moral and philosophical ideas as to do with their
    personal benefit.

[2] When we compare strategies for voting in a voting system, to `do
    better' is to be more likely to get a situation one prefers.