> you wrote > > If a majority has a 100% chance of getting their candidate elected, > > then there is no incentive for them to trade.? If the voters are 100% > strategic, they will know this. > > Yes, although some Range Voting supporters try hard to convince us of > the opposite, it seems.
Well, your example is under the assumption of perfect information. I think in the near perfect balance of your example and without perfect information, range or approval would probably elect the compromise as a reasonably large number of voters would approve the compromise as well as their favourite instead of risking their hated candidate wins. As the majority for A gets larger (say >55%), A's supporters would be advised to switch to bullet voting just for A. I think that approval is a good and practical voting method. However, the ideal method is one that gives people an incentive for honest ratings and elects the candidate that is socially optimal, i.e a candidate who would be a 'Kaldor-Hicks optimal' candidate. If there is more than one optimal, then use random ballot to decide which one, but a tie isn't that likely. One issue with random processes is that they don't work well for a legislature. A majority would just keep asking that the vote be repeated until they win it. Saying that a re-vote cannot occur unless the situation changes would require that a definition of a change in the situation be decided. Also, people have a certain level of distrust for random processes. I don't think people would accept a President who was elected even though he only had a 1% chance of winning. I am not sure what the threshold is before it would be acceptable (some people would object to a 49% candidate winning instead of a 51% candidate). > > Optimal utility via trade requires that voters have something to > > trade, and fractions of a win probability seems to be quite a > > reasonable solution. > > I cannot really imagine any other thing unless we consider money > transfers... There is a method called CTT voting where money is used and in theory, it provides an incentive for everyone to be honest. However, it requires each voter to act completely independently. Also, it weakens the secret ballot. Also, it only requires payment in a small number of cases, where the result is close. In a landslide, nobody has to pay. http://rangevoting.org/CTT.html It would probably not work in practice, especially for large elections. Most of the issues are listed on the linked page. For a legislature, you could trade future votes instead of money. One issue is that it needs to be a secret ballot for CTT to work, (otherwise parties can control the votes by disciplining party members who vote the 'wrong' way after the vote is completed and made public). However, it needs to be a public ballot so that the voters know if their legislator is voting in their best interests. In Germany, motions of no confidence in the Chancellor (head of government) are handled by a secret ballot that requires an absolute majority of their legislature to pass. This is used to change the head of government, so I guess not all legislatures have public votes for everything. Raphfrk -------------------- Interesting site "what if anyone could modify the laws" www.wikocracy.com ________________________________________________________________________ AOL's new homepage has launched. Take a tour at http://info.aol.co.uk/homepage/ now.
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