2010-05-18

New Scientist: Why democracy is always unfair

Toby at work sent me an interesting New Scientist article on voting systems.

Entitled 'Electoral dysfunction: Why democracy is always unfair', it argues that due to Arrow's Impossibility Theorem, you can never have a perfect voting system. The problem with this argument is that Arrow's Theorem only applies to voting systems where the candidates are put into an ordered list.

Under the range voting system, the voter gives each candidate points out of 10 (or some other number). All the points for each candidate are added up, and the candidate with the highest number of points is the winner. Since range voting doesn't require an ordered list, Arrow's Theorem doesn't apply.

3 comments:

  1. There was a piece on the voting system on yesterdays material world, bbc r4.

    I didn't manage to listen to it all, so can't comment on it. But you can get the pod cast, or listen again.

    ReplyDelete
  2. Yeah, the author didn't include Score Voting. He replied to me:

    New Scientist asked me to write a piece on the mathematical
    paradoxes associated with elections. I had 1500 words to
    play with. Many items were passing references
    to alert readers to interesting related topics. I wasn't
    writing a technical treatise.

    Any interested reader can
    get the full story from the Internet. Readers
    should also understand that the tone of the piece was not
    a scholarly critique of electoral systems, but a bit of fun
    with some maths in the context of a coming election.

    They will also understand, I would hope, that subeditors
    at magazines like to spice up the narrative a little, and
    that the extent to which the various systems are 'unfair'
    is often minor - as the examples show.

    ReplyDelete
  3. New Scientist asked me to write a piece on the mathematical
    paradoxes associated with elections. I had 1500 words to
    play with. Many items were passing references
    to alert readers to interesting related topics. I wasn't
    writing a technical treatise.

    Any interested reader can
    get the full story from the Internet. Readers
    should also understand that the tone of the piece was not
    a scholarly critique of electoral systems, but a bit of fun
    with some maths in the context of a coming election.

    They will also understand, I would hope, that subeditors
    at magazines like to spice up the narrative a little, and
    that the extent to which the various systems are 'unfair'
    is often minor - as the examples show.

    ReplyDelete