[EM] Saari's Basic Argument

[Forest Simmons]

On Thu, 16 Jan 2003, Steve Barney wrote:

> Forest:
>
> In your example,
>
> >66 A>B>C
> >34 B>C>A
>
> If you give second preferences any more than 16/33 of the weight which you
> give to the first prefs, the winner is B; since:

No need of giving weights to see all the mischief that could come from
giving the win to B.

Assuming the rankings are sincere, we see that A has clear majority
support.

If Borda is used to decide the election, 66 percent of the voters will
regret having ranked B and C sincerely.

That majority could defend themselves by running a clone D of their own:

66 A>D>B>C
34 B>C>A?D

It wouldn't matter if the BC faction voted A over D, or D over A, Borda
would give the win to A.

So Borda encourages a "race to the bottom" in cloning.

Forest

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