[EM] IRV vs Plurality

[Terry Bouricius]

Response to Robert's statement...
"I guess I still haven't heard a good justification for why the Condorcet winner, if one exists, should *ever* be rejected as the elected winner."
...

Imagine this scenario. ..

A highly polarized electorate with a three candidate race. Only two candidates are seen by the media and the public as viable, with 49% favoring candidate A and 46% favoring B, and 5% favoring C slightly over A. Most voters don't know much about C, but C has carefully avoided alienating any constituency by only stressing his likeability, rather than issues. However while the supporters of both A and B don't think much of C they rank C second because they subscribe to the "anybody but X" notion. The A supporters all rank A>C>B, while the B supporters all rank B>C>A and the C voters all rank C>A>B

49 A>C>B
46 B>C>A
  5 C>A>B

In a traditional runoff or IRV, A would win over B, after C's elimination by 54 to 46. I think that is a reasonable expression of "the public will" though not the only possible one.

With Condorcet, 
C would defeat A by 51 to 49
and C would defeat B by 54 to 46

Thus C is the Condorcet winner. 

It is certainly justifiable to argue that C is the "rightful" winner. But it is not unreasonable to say that C is not the "rightful" winner, since 95% of the voters are highly dissatisfied with C being elected. This is where the Range voting utility advocates enter the fray. My point is merely that the Condorcet-winner criterion is desirable in most cases, but not the only legitimate, nor ultimate criterion.

Terry Bouricius
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