2010/4/28 Juho <juho4...@yahoo.co.uk> > On Apr 28, 2010, at 9:19 PM, Peter Zbornik wrote: > > Hello, > > I have some catching up to do here. > I need to think more about some of the different methods and the proposals > I have gotten. > Some of the methods are new to me. > As I am a layman it takes time to understand them. > > Condorcet methods have not been used in politics yet, I think. > Are there by any chance other methods to elect centrist presidents? > > > The most common single-winner methods (plurality, top-two runoff, IRV) are > known not to be "centrist oriented". For example in the quite common set-up > where we have two extremists and one centrist with slightly less support > they all elect one of the "extremists". >
That's with honest votes. Of course, voters can strategize to counteract the system's tendency. In the US-2000 election, some Gore ("center-left") voters had a slogan that "a vote for Nader ("left") is a vote for Bush (we all know how he turned out)." This slogan encapsulates the perverse strategy incentives of an "extremist oriented" system like Plurality, or, to a slightly lesser extent, IRV. > > Approval and Condorcet are more centrist oriented. They are both also old > and well tested methods although they have not been widely used in public > political elections. > > One problem with Approval (that was not mentioned yet) is the limited > expressive power of the Approval vote and resulting problems in choosing the > right strategy, e.g. when there are three leading candidates and one should > approve either one or two of them. That is problematic e.g when left wing > has 2 candidates and is is bigger than right wing that has 1 candidate. (In > Approval voters are generally assumed to vote strategically and not just > sincerely list candidates that they consider "approvable".) > This is exactly the problem that Bucklin is intended to solve. Bucklin is essentially multi-round approval using one ballot. It's not as theoretically clean as many methods, so there are some desirable criteria that it doesn't strictly satisfy; but it's a simple, practical method, both for voting and for counting. (Of course, as always, I'm referring to the equal-rankings-allowed versions of Bucklin.) Of course, the issue with Bucklin is that it uses a different (simpler) balloting style than STV or Condorcet. So if you used Bucklin for the single-winner method, you'd either need to take two ballots, take a combined ballot (with some ficticious "cutoff" candidates - possibly hard to understand), or use a proportional method like RBV which is based on Bucklin ballots. JQ
---- Election-Methods mailing list - see http://electorama.com/em for list info