[EM] IRV vs Plurality

[Stéphane Rouillon]

Mr. Bristow-Johnson is right.
I made a mistake. IRV did *not* produce the same result that FPTP (with 
identical sets of preference) would have in Burlington..
I meant they both did not elect the most popular winner as he elegantly 
wrote.

But I would underline the fact that my observations, that go without 
saying according to Mr Bristow-Johnson,
("I can observe that IRV allows more often to obtain a Condoret winner 
when plurality fails, than plurality finds a Condorcet winner when IRV 
fails.")
seem to be contradicted by Mr Lomax own data....

S. Rouillon.

robert bristow-johnson a écrit :
>
> On Jan 10, 2010, at 1:57 PM, Stéphane Rouillon wrote:
>
>> from the data you produce, I agree that for the Burlington election, 
>> IRV did produce the same result
>> FPTP would have produced.
>
> it's *not* the same result.  it is a worse result if you force the 
> majority to vote strategically (which is what FPTP would do) than if 
> you punish a minority for not voting strategically (which is what IRV 
> did).  FPTP would have elected Kurt Wright to the dismay of 66% while 
> IRV elected Bob Kiss to the dismay of far fewer because the Dems in 
> Burlington like Progs more than they like GOPs.
>
>> However, nobody can generalize this perticular case to any election.
>
> but it *does* serve as a useful object lesson.
>
>> I can observe that IRV allows more often to obtain a Condoret winner 
>> when plurality fails, than plurality finds a Condorcet winner when 
>> IRV fails.
>
> well, that goes without saying.
>
>> So I claim IRV is more reliable than plurality.
>
> it saved Burlington from electing the 3rd most popular candidate and 
> elected the 2nd most popular candidate.  the candidate preferred by 
> the majority of voters (and thus would beat any other candidate in the 
> final round had he been it the final round) was eliminated before the 
> IRV final round.
>
> it's a mixed result for the majority of Burlington voters.  but it's 
> still better than Plurality or the Delayed-Runoff (which is what would 
> happen if the old law was in force).
>