Let M be the matrix whose row i column j element M(i,j) is the number of 
ballots on which i is ranked 
strictly above j plus half the number of ballots on which neither i nor j is 
ranked.

In particular, for each k the diagonal element M(k , k) is half the number of 
ballots on which candidate k 
is unranked.

Now think of M as the payoff matrix for the row player in a zero sum game.

Elect the candidate that would be chosen by the optimal strategy of the row 
player.

[End of Method Definition]

Remarks:

If there is a saddle point (i, j) such that the element M(i,j) in that position 
is the lowest in its row and the 
highest in its column, then the game is deterministic, and the winner is 
candidate j.  

In this case candidate j is the same as the MMPO winner under the Symmetric 
Completion Bottom rule, 
i.e. the Least Resentment Voting (LRV) winner.

However in general the optimal strategies are mixed, which means that the 
players' moves are 
determined by probability distributions or "lotteries."  In this case, the 
column player's optimal lottery is 
used to pick the winner.

By definition this method chooses the winner in a way that minimizes its 
expected opposition, so on 
average it accomplishes more completely the heuristic justification of LRV than 
LRV itself does.

In other words use of this method will (on average) distress the opposition 
less than any other method.

So let's call it the Least Expected Umbrage method or LEU.

We need to check that it passes all of the tests and satisfies all of the 
properties that we think are most 
important.

I know that most people are prejudiced against chance, so determinism is high 
on their list of 
importance. But I hope that future generations will be more enlightened on this 
score, and embrace the 
judicious use of chance.

When they look back and see that we anticipated some of their ideas, they might 
forgive us for some of 
our other oversights.

Forest

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