Multi-winner Condorcet, vs STV

Ian Jackson ijackson at
Fri Dec 11 15:07:51 UTC 2009

Barak A. Pearlmutter writes ("Re: Multi-winner Condorcet, vs STV"):
> Having studied this a bit, I would suggest that the best currently
> available multiwinner election system for our purposes here, i.e., for
> proportional representation, is Reweighted Range Voting, see

I'm strongly opposed to range voting.  Range voting means you need to
know where the likely controversies are to effectively cast your vote.
This is because you need to know how other people are likely to vote
to know where to "spend" your influence.

So the extra expressiveness (being able to weight some preferences as
more important than others) is not a benefit in this case; it is a
hindrance because the appropriate way to vote so as to maximise the
desired outcome becomes hard to discover and compute.

Or to put it another way: range voting inherently implies making
tactical voting important.  Eliminating the need for voters to vote
tactically rather than honestly should be high up on our list of
desirables for a voting system.

Hence my suggestion that we should use STV.  STV does have some edge
cases and problems but they're rare and largely theoretical.  With STV
voters can just rank their candidates and can safely do so without
considering the behaviour of the other voters, and the results are
reasonably proportional and rarely anomalous.


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