[EM] clone proofing Copeland

Chris Benham chrisjbenham at optusnet.com.au
Wed Jan 3 23:32:35 PST 2007

Simmons, Forest wrote:

>In view of comments and suggestions from Chris, Warren, Markus, and all (for which I thank you all warmly) I would like to suggest that this attempt at clone proofing Copeland be used in a three slot setting.
>I'll restate it for the record:
>For each candidate X let p(X) be the probability that a candidate chosen by random ballot(s)*  is pairwise defeated by X.
>Elect the candidate with the highest value of p(X).
>*Note that with three slots you cannot expect a single random ballot to single out a candidate.  Further random ballots are usually needed to narrow it down.  A Markov process can be used to calculate the probabilities.
34: A>E
33: B>E
33: C>E

How does the "Markov process" work to elect the Condorcet winner E in 
this example?

Chris Benham

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