[EM] So I got an email...

robert bristow-johnson rbj at audioimagination.com
Sun Apr 10 11:52:09 PDT 2022


But it's *because* of the Condorcet failure that the IIA failed. The Condorcet winner (if one exists) must be kept out of the final round.  The candidate that loses in the final round and displaces the CW from the final round is the spoiler. Then voters for the spoiler who ranked the IRV winner lowest are punished for not betraying their favorite.But I think Precinct Summability is what's getting the most scrutiny here.  We look at Maine who had to haul 600,000 ballots from every corner of the state and didn't have an outcome for 4 days.Powered by Cricket Wireless------ Original message------From: Richard, the VoteFair guyDate: Sun, Apr 10, 2022 1:34 PMTo: election-methods at lists.electorama.com;Cc: Subject:Re: [EM] So I got an email...This discussion about IRV and FairVote (not VoteFair) is motivating me 
to point out my different perspective of the Burlington VT mayoral 
election result.

IMO the biggest failure in the Burlington was an IIA -- independence of 
irrelevant alternatives -- failure.  Not the Condorcet failure.

If the Republican candidate had not been in the race, the Democrat would 
have won instead of the Progressive.  That didn't happen because the 
Republicans voted sincerely.  If they had voted tactically by ranking 
the Republican after the Democrat and before the Progressive, their 
ballots would not have gotten "stuck" supporting the Republican during 
the top-three counting round where the Democrat was eliminated.

Of course the major weakness of IRV is that the counting does not look 
deeply into all the marks on all the ballots.

This weakness can be reduced by removing any clearly unpopular 
candidates, such as the Republican in the Burlington election.  I 
suggest eliminating the "pairwise losing candidate" -- which is the 
"Condorcet loser" among the remaining candidates.

When the FairVote folks defend the Burlington result they spin it to be 
a Condorcet failure and point out that a candidate who is second-ranked 
on all the ballots doesn't really deserve to win.  That's somewhat 
reasonable.

But their only defense against the IIA failure criticism might be that 
it rarely happens.  OK, but it does happen.  And it happens because the 
method does not look deeply enough into all the marks on all the 
ballots.  And that's an obvious flaw in IRV.

Many fans of STAR voting initially supported IRV until this flaw (and 
another one I'll introduce below) became obvious.  Alas, instead of 
choosing to support a better way to count ranked ballots, the STAR fans 
created their own kind of ballot that isn't compatible with anything 
else.  Now that STAR voting momentum is slowing down, it's time to 
consider resolving the conflicts between IRV, STAR, and better 
ranked-choice ballot methods.

That's why I recently suggested a way to improve the Ranked Robin method 
that some STAR fans created.

Yet ultimately what's needed is for Rob Richie -- the leader of the 
FairVote organization -- to admit that IRV and STV are not acceptable as 
they are currently counted, yet can be improved in simple ways to make 
them widely acceptable.

The other flaw in IRV is that the FairVote counting method does not 
allow a voter to mark two or more candidates at the same preference 
level.  This is easy to fix (as I've discussed here before).

These simple improvements to IRV and STV would yield a compromise that I 
believe would be acceptable to STAR fans, math-savvy Condorcet fans, the 
FairVote organization, and me, the VoteFair guy.

Richard Fobes
The VoteFair guy


On 4/9/2022 6:49 PM, robert bristow-johnson wrote:
> ... from Rob Richie.  I am trying to be nice (because I'm in the last throes of my struggle to keep Vermont from repeating a mistake) and I saw a small numerical error in the FV page at https://www.fairvote.org/research_rcvwinners  regarding non-monotonicity (and Burlington 2009).  So I wrote him (the first time since 2017) and he wrote back.  That's a lot better than I can say for Aaron Hamlin.
>
> Anyway, in our friendly back-and-forth, Rob brought up a contrived example of an election where they purport that Hare works better than Condorcet.  In this rhetorical example there is a dead-tie symmetry.  And Rob suggested that it gets resolved with "RCV - Jump ball" or "jump ballot".  What, exactly, is "jump ballot"?  Is it drawing a ballot out of the entire pile at random?  Like sortition?
>
> FYI This is the context:
>
> ___________________________
>
>
> A and B, polarizing candidates
> C is Condorcet candidate in third
>
> 1st choices
> A - 40%
> B - 40%
> C - 20%
>
> Preferences (honest)
> ACB - 40%
> BCA - 40%
> CAB - 10%
> CBA - 10%
>
> RCV - Jump ball
> Condorcet - C wins 60%-40% over both A and B
>
> BUT... polls show this to be the case, and backers of A and B both know the only way they can win is to keep C out of it. So their backers bury C
>
> Preferences (strategic, both major campaigns)
> ABC - 40%
> BAC - 40%
> CAB - 10%
> CBA - 10%
>
> C is no longer the condorcet winner, as both A and B seem to defeat C by 8-020.  The winner will be decided by a jump ballot tally between A and B. Strategy worked
>
> Let's suppose only one side decides to do this. It probably backfires, but still gives them a chance depending on the tiebreaker., So you might get:
>
> Preferences (strategic, only 1 major campaign - backers of B)
> ACB - 40%
> BAC - 40%
> CAB - 10%
> CBA - 10%
>
> Condorcet:  C over B 60-40  but A over C 80-20 and jump ball with A and B. So B voters may end up helping A win if they lose the jump ballot, they create a cycle and then win an IRV tiebreaker if they win the tiebreaker between A and B.
>
> ___________________________
>
>
> I don't mind hearing opinions from anyone on the list about this scenario, but what I most want is a good understanding of exactly what Rob means by "jump ballot".  (And I know I could ask him, but I wanna ask you dawgs instead.)
>
> I told Rob about my paper about Burlington 2009. https://tinyurl.com/2tety9tj  I dunno if that was a mistake or not.
>
> About my struggle in Vermont: I have gotten the attention of several legislators in Vermont.  Several RCV bills have stalled and languished in committee and will die when this legislative session ends at year's end.  But the Burlington RCV charter change has been revived and has passed the Vermont House (but they took out the specific language of exactly how the RCV election method will work, bumping that back to Burlington city council).  It's going before the Vermont Senate Government Operations Committee in the near future and I expect to be visiting the state capitol again to lobby.
>
> I thank y'all.
>
> robert
> --
>
> r b-j . _ . _ . _ . _ rbj at audioimagination.com
>
> "Imagination is more important than knowledge."
>
> .
> .
> .
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