[EM] One pager about what happened in Vermont

robert bristow-johnson rbj at audioimagination.com
Sat Mar 6 16:16:52 PST 2010

On Mar 6, 2010, at 4:18 PM, Rob Lanphier wrote:

> The key insight I had was to break the electorate up by their first  
> preference, and then do Schulze-wv tallies on each subset of  
> ballots.  That yielded a reasonably realistic way to lay out the  
> candidates in a 2D spatial representation.

Schulze?  For the viewer who might have trouble visualizing IRV  
(despite your quite good layout, i really like what you're doing)?

listen the Condorcet result of the 2009 election is unambiguous.  it  
gets ordered [M]ontroll 1st, [K]iss, [W]right, [S]mith, and [H] 
Simpson last.  every candidate ordered higher beats any candidate  
ordered lower in a head-to-head race. i think there are 10 head-to- 
head pairings.

  M 4064
  K 3477

  M 4597     K 4313
  W 3664     W 4061

  M 4570     K 3944     W 3971
  S 2997     S 3576     S 3793

  M 6263     K 5515     W 5270     S 5570
  H  591     H  844     H 1310     H  721

i like a triangle instead of a defeat matrix, at least if it can be  
ordered so nicely. "H" is for "Homer".  notice how well he does  
against Wright.  what does that tell us about Wright's "negatives"?   
and Wright *barely* beast Smith (and Independent with no party  
backing).  i just can't believe the New North Enders, who were  
primarily behind the repeal movement, think that Wright was the guy  
who was robbed, because he had the plurality of first-choice votes.

anyway, i would be representing your groups of people in terms the  
number pairs above.  at least in terms of the pairs on top of the  
columns.  and you can note that the K 4313 W 4061 pair is the same  
pair that we see in the IRV final round.  or maybe the pairs in the  
first column are the salient groups to portray.

so, my suggestion is, since there was no Condorcet cycle anywhere in  
that ordered triangle, why not depict Condorcet as the method that  
chooses the candidate that each majority agrees is the preferred  
candidate?  i wouldn't mess around with Schulze or any method that  
really exists as a meaningful and fair approach to deciding a winner  
if there is no Condorcet winner.  i mean, do what you wanna do, but  
if i were to use 2009 Burlington as a case study for what happened  
with IRV and what would have happened if some other method (like  
Condorcet or Plurality), i would depict the Schulze method in an  
"advanced" slide.  2009 Burlington doesn't need it.

and i think it would be important to compare Kiss-Wright pair (the  
IRV final round) to the Montroll-Kiss pair as a visual for why the  
IRV might have picked a dubious result.

> Everything discussed above is available from this page:
> http://wiki.electorama.com/wiki/ 
> 2009_Burlington,_Vermont_Mayoral_Election

my numbers come from the files from the clerk's office.  do check out  
Warren's page at http://rangevoting.org/Burlington.html .  there are  
small discrepancies, but no more than 5 votes.

i mean, you could make for nice diagrams for how the Condorcet winner  
is kept out of the final round, and then if 372 out of 1513 W>M>K  
voters vote strategically and rank Montroll above Wright, they can  
prevent Kiss from winning.  those people aren't happy that casting  
their primary vote for Wright actually caused Kiss to be elected.

and you can show how if 744 Wright voters (comes out of the 495 W>K>M  
and no more than 589 of the 1289 W voters) actually changed their  
mind on the way to the polls and decided that they liked Bob Kiss  
better than Wright.  then, by changing their vote primary vote to  
Kiss, they actually cause Kiss to lose.

i mean, if i wanted to see, in a nutshell, what happened, what went  
wrong, what could have gone wronger with IRV.

this looks very cool, Rob.


r b-j                  rbj at audioimagination.com

"Imagination is more important than knowledge."

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