Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?

2009-11-16 Thread Abd ul-Rahman Lomax
At 12:22 PM 11/8/2009, Terry Bouricius wrote: A somewhat more accessible (and available online for free) analysis of strategic vulnerability of various methods is in this doctoral paper by James Green-Armytage (Strategic voting and Strategic Nomination: Comparing seven election methods). He

Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?

2009-11-16 Thread Andrew Myers
Abd ul-Rahman Lomax wrote: Notice that the requirement of Arrow that social preferences be insensitive to variations in the intensity of preferences was preposterous. Arrow apparently insisted on this because he believed that it was impossible to come up with any objective measure of

Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?

2009-11-16 Thread Jonathan Lundell
On Nov 16, 2009, at 10:53 AM, Andrew Myers wrote: Abd ul-Rahman Lomax wrote: Notice that the requirement of Arrow that social preferences be insensitive to variations in the intensity of preferences was preposterous. Arrow apparently insisted on this because he believed that it was

Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?

2009-11-16 Thread Jonathan Lundell
On Nov 16, 2009, at 11:53 AM, Stéphane Rouillon wrote: Would this suggest it could be possible to overcome Arrow's theorem using range ballots? I do not want to say Arrow's theorem is false. All I ask is: Are prefential ballots one of the hypothesis used in Arrow's theorem proof? Because

Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?

2009-11-16 Thread Andrew Myers
Jonathan Lundell wrote: This is in part Arrow's justification for dealing only with ordinal (vs cardinal) preferences in the Possibility Theorem. Add may label it preposterous, but it's the widely accepted view. Mine as well. Arrow's Theorem seems like a red herring in the context of the

Re: [EM] Dectecting Clone Sets

2009-11-16 Thread Juho
How should we continue from this? Should we divide the seats proportionally at top level to the top level branches of the tree, and then repeat the process towards the leaves. What are the main differences between the tree if derived from the ballots using clone analysis vs. if given by

Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?

2009-11-16 Thread Jonathan Lundell
On Nov 16, 2009, at 2:15 PM, Andrew Myers wrote: Jonathan Lundell wrote: This is in part Arrow's justification for dealing only with ordinal (vs cardinal) preferences in the Possibility Theorem. Add may label it preposterous, but it's the widely accepted view. Mine as well. Arrow's Theorem

Re: [EM] Anyone got a good analysis on limitations of approvalandrange voting?

2009-11-16 Thread Terry Bouricius
Yes, Arrow's Theorem does assume ordinal ranking, since the whole goal of the decision process was to find a community-wide decision about how options should be placed in an order from favorite to least favorite (rather than just find a winner), and he expressly dismissed cardinal scores as

Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?

2009-11-16 Thread Andrew Myers
Jonathan Lundell wrote: I don't have his proof in front of me (I'm on the road), but I'm pretty sure that it assumes ordinal ranking. It seems fairly obvious that the theorem also holds for ratings, because ratings can be projected onto rankings without affecting any of Arrow's criteria.

Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?

2009-11-16 Thread Raph Frank
The theorem states (from wiki) that there is no method which has the following properties: * If every voter prefers X over Y, then the group prefers X over Y. * If every voter prefers X over Y, then adding Z to the slate won't change the group's preference of X over Y. * There is no

Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?

2009-11-16 Thread Kevin Venzke
Strictly speaking I don't think Range is an election method according to Arrow, because you can't determine the winner from the orderings. It would be hard to make statements about the effect of introducing candidate Z when you don't have an assumption about what the outcome is based on. You can

Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?

2009-11-16 Thread Jonathan Lundell
On Nov 16, 2009, at 4:58 PM, Raph Frank wrote: The theorem states (from wiki) that there is no method which has the following properties: * If every voter prefers X over Y, then the group prefers X over Y. * If every voter prefers X over Y, then adding Z to the slate won't change the

Re: [EM] Dectecting Clone Sets

2009-11-16 Thread Kristofer Munsterhjelm
fsimm...@pcc.edu wrote: Here's a suggestion for detecting clone sets based on Range Ballots: Define the distance between two candidates as the square root of the sum (over the ballots) of the squared diffference of their respective ratings. If the ballots are approval style, this becomes the