[EM] RCV in SF Mayoral election
Christopher Colosi
colosi at gmail.com
Mon Jun 11 08:45:37 PDT 2018
How is the ballot image file laid out? It seems like a horrible choice for
formatting. Is there any delimiter between ballots, or is this just one
gigantic string of numbers?
On Sun, Jun 10, 2018 at 10:42 PM robert bristow-johnson <
rbj at audioimagination.com> wrote:
>
>
>
>
> boy this is embarrassing. i didn't realize they were still counting and
> that the lead has changed. looks like London Breed is ahead and will
> likely win the STV contest.
>
> and, from Brian's initial analysis, it doesn't look like the Condorcet
> Winner will be different from the STV winner. so no Burlington 2009
> situation.
>
> L8r,
>
> r b-j
>
>
>
> ---------------------------- Original Message ----------------------------
> Subject: Re: [EM] RCV in SF Mayoral election
>
> From: "robert bristow-johnson" <rbj at audioimagination.com>
> Date: Sun, June 10, 2018 10:23 pm
> To: "EM" <election-methods at lists.electorama.com>
> Cc: "Brian Olson" <bql at bolson.org>
> --------------------------------------------------------------------------
>
>
>
> >
> >
> >
> > Thank you Brian for doing this. Looks like Leno is the legit winner and
> STV and Condorcet agree.
> > However, the Leno-Breed pair wise tally in the defeat matrix should be
> exactly the same as the STV final round result. So something is wrong
> somewhere.
> > But thanks for doing this. I was about to code up a MATLAB program to
> parse and count this thing.
> >
>
> > --r b-j rbj at audioimagination.com
>
>
> > "Imagination is more important than knowledge."
> >
> >
> >
> >
> > -------- Original message --------
> >
> From: Brian Olson <bql at bolson.org>
> > Date: 6/10/2018 7:46 AM (GMT-08:00)
> > To: EM <election-methods at lists.electorama.com>
> > Subject: Re: [EM] RCV in SF Mayoral election
> >
> > Ok, a few lines of Python poking the raw data shows I must have some bug
> in my Condorcet implementation. Digging into that...
> > On Sun, Jun 10, 2018 at 10:08 AM, Greg Dennis <
> greg.dennis at voterchoicema.org> wrote:
> > Brian, how is it possible that those differ? Since all the other
> candidates are eliminated in the final round, shouldn't that necessarily be
> the same as the pairwise contest between those two?
> >
> > On Sun, Jun 10, 2018, 9:46 AM Brian Olson <bql at bolson.org> wrote:
> > I processed the latest data (2018-06-09) and posted the results of the
> SF Mayor election using a few algorithms:
> https://bolson.org/~bolson/2018/SF_Mayor_20180605.html
> >
>
> > The Condorcet win is now 97436 to 91740 for Leno over Breed.The IRV
> final round is still just 94783 to 94393.
>
>
> >
> > I'm using my software posted at https://github.com/brianolson/voteutil
> > commands (needs maven installed for compiling Java, and needs Python3):
>
> > curl -O
> http://www.sfelections.org/results/20180605/data/20180609/20180609_ballotimage.txtcurl
> -O
> http://www.sfelections.org/results/20180605/data/20180609/20180609_masterlookup.txt
> > (mkdir -p ~/psrc && cd ~/psrc && git clone
> https://github.com/brianolson/voteutil.git && cd ~/psrc/voteutil/java &&
> mvn package)python3 ~/psrc/voteutil/python/rcvToNameEq.py -m
> 20180609_masterlookup.txt -b 20180609_ballotimage.txt -o
> 20180609_%s.nameqjava -jar ~/psrc/voteutil/java/target/voteutil-1.0.0.jar
> --rankings --full-html --explain -i 20180609_Mayor.nameq >/tmp/a.html
>
>
> >
> > On Sat, Jun 9, 2018 at 9:33 PM, Greg Dennis <
> greg.dennis at voterchoicema.org> wrote:
> > I quickly looked at the vote data and saw that lots of ballots are
> categorized as "Exhausted by Over Votes" and "Under Votes," but there is no
> data indicating exactly how those ballots were marked, so we lack enough
> information to be sure of final results.
> > Actually, all the data you need is available from that page. The "Ballot
> Image" file will give you the full cast vote record of every individual
> ballot, and the "Master Lookup" is the legend that tells you what each
> number means. If you have trouble interpreting the numbers, just ping me!
> >
> > On Sat, Jun 9, 2018 at 4:36 PM, VoteFair <electionmethods at votefair.org>
> wrote:
> > On 6/9/2018 6:25 AM, Greg Dennis wrote:
> >
> >> San Francisco always make the cast vote record public:
> >
> >>
> https://sfelections.sfgov.org/june-5-2018-election-results-detailed-reports
> >
> >
> >
> > I quickly looked at the vote data and saw that lots of ballots are
> categorized as "Exhausted by Over Votes" and "Under Votes," but there is no
> data indicating exactly how those ballots were marked, so we lack enough
> information to be sure of final results.
> >
> >
> >
> > Converting instant-runoff counts into pairwise counts might be (probably
> is?) possible, but I don't have time to do that analysis.
> >
> >
> >
> >> The probability of IRV not elected the Condorcet winner appears to be
> >
> >> exceedingly low in practice. We're up to about ~200 IRV elections
> >
> >> conducted nationwide since 2004 and Burlington 2009 is the only
> >
> >> case so far.
> >
> >
> >
> > Yes, circular ambiguity -- in which there is no Condorcet winner -- is
> rare when the number of ballots exceeds a few hundred.
> >
> >
> >
> >> On Sat, Jun 9, 2018 at 2:07 AM, robert bristow-johnson
> >
> >> <rbj at audioimagination.com <mailto:rbj at audioimagination.com>> wrote:
> >
> >> the limitation to only three levels of ranking is a problem. if
> >
> >> someone ranked all three levels and none of the candidates ranked
> >
> >> were either London Breed nor Mark Leno, that voter was effectively
> >
> >> "disenfranchised" by being unable to weigh in on the final choice of
> >
> >> choosing the mayor.
> >
> >
> >
> > Based on a very quick guesstimate it looks like about 30 or so ballots
> had this issue. Right?
> >
> >
> >
> > That's not a big number, but a fair counting method -- such as pairwise
> counting -- would not have to discard any ballots.
> >
> >
> >
> > The bigger number is "under votes" and admittedly pairwise counting
> cannot compensate for a voter saying "here is the only acceptable choice"
> (or two choices in this case).
> >
> >
> >
> > It's great that these results are getting analyzed by people who do not
> drink the FairVote kool-aid.
> >
> >
> >
> > In haste,
> >
> > Richard Fobes
> >
> > "The VoteFair guy"
> >
> >
> >
> >
> >
> > On 6/9/2018 6:25 AM, Greg Dennis wrote:
> >
> >
> > San Francisco always make the cast vote record public:
> >
> >
> https://sfelections.sfgov.org/june-5-2018-election-results-detailed-reports
> >
> >
> >
> > Based on the most recent analysis of these numbers that I saw, Leno was
> >
> > indeed the Condorcet winner, and if Breed were to beat Leno in the final
> >
> > round, she would then necessarily be the Condorcet winner. The
> >
> > probability of IRV not elected the Condorcet winner appears to be
> >
> > exceedingly low in practice. We're up to about ~200 IRV elections
> >
> > conducted nationwide since 2004 and Burlington 2009 is the only case so
> far.
> >
> >
> >
> > On Sat, Jun 9, 2018 at 2:07 AM, robert bristow-johnson
> >
> > <rbj at audioimagination.com <mailto:rbj at audioimagination.com>> wrote:
> >
> >
> >
> >
> >
> > Richard, a few points:
> >
> >
> >
> > the limitation to only three levels of ranking is a problem. if
> >
> > someone ranked all three levels and none of the candidates ranked
> >
> > were either London Breed nor Mark Leno, that voter was effectively
> >
> > "disenfranchised" by being unable to weigh in on the final choice of
> >
> > choosing the mayor. however, i think the news media made it clear
> >
> > that the race was really gonna be between Leno, Breed, and Kim, so
> >
> > these fringe voters might have a chance to insincerely mark either
> >
> > Leno or Breed as their 3rd choice and betray their *true* third
> >
> > choice and, in doing so, have an effect in the final round.
> >
> >
> >
> > ignoring the problem of only 3 ranking levels, it is not possible
> >
> > that London Breed is the Condorcet Winner (a.k.a. "pairwise
> >
> > champion"). it might be the case that Mark Leno or Jane Kim is the
> >
> > Condorcet Winner and if the latter is the case, this is another real
> >
> > indictment against STV or IRV as a method of tallying RCV. and your
> >
> > reverse namesake, FairVote, is partially (or mostly) to blame.
> >
> >
> >
> > i wonder if the City of SF has a file of all of the cast and scanned
> >
> > ballots and the full ranking for each. if so, and if they release
> >
> > it to the public, we can investigate if there is a Condorcet Winner
> >
> > and if that CW is or is not Mark Leno. this would be interesting.
> >
> >
> >
> > L8r,
> >
> >
> >
> >
> >
> >
> >
> > r b-j
> >
> >
> >
> >
> >
> >
> >
> > > On 6/8/2018 6:24 PM, Christopher Colosi wrote:
> >
> > > > ... She stated “This is the system we are working with. That’s
> >
> > > > a discussion we can have at a later time. For now, we’re stuck
> >
> > with it.”
> >
> > > > - insinuating it is not fair. I was quite bothered to have a Dem
> >
> > in a
> >
> > > > progressive city insinuate that first past the post is more
> >
> > fair. ...
> >
> > >
> >
> > > This remark does not imply support for first past the post (FPTP,
> >
> > a.k.a
> >
> > > plurality counting).
> >
> > >
> >
> > > There are other ways to count the preference marks on
> "ranked-choice"
> >
> > > ballots. In particular, pairwise counting could be used instead of
> >
> > > instant-runoff counting, and that is fairer than FPTP.
> >
> > >
> >
> > > > 1. May not elect majority candidate
> >
> > > > ...
> >
> > > > Is this common? This is
> >
> > > > probably an abnormally close race. Thoughts?
> >
> > >
> >
> > > I doubt the voters would regard this as a close race if they had
> been
> >
> > > able to fully rank all the choices. The 3-choice limitation is
> >
> > > simplistic, and complicates the counting.
> >
> > >
> >
> > > Pairwise counting does not result in any exhausted ballots.
> Unmarked
> >
> > > choices are an indication that the choices are equally disliked.
> And
> >
> > > multiple candidates being marked at the same preference level is
> >
> > also no
> >
> > > problem.
> >
> > >
> >
> > > In other words, the ballots contain enough information that they
> >
> > can be
> >
> > > counted in other ways, besides instant-runoff counting. Those
> >
> > alternate
> >
> > > counting methods could reveal a clearer outcome.
> >
> > >
> >
> > > In haste,
> >
> > > Richard Fobes
> >
> > >
> >
> > >
> >
> > > On 6/8/2018 6:24 PM, Christopher Colosi wrote:
> >
> > >> Curious to hear people’s thoughts on some issues.
> >
> > >>
> >
> > >> 1. May not elect majority candidate
> >
> > >> In SF, we restrict to 3 choices to simplify the process. As the
> vote
> >
> > >> currently stands, 144 votes separate the top two candidates
> >
> > (<0.1%) and
> >
> > >> over 16,000 ballots have been exhausted (all 3 choices
> eliminated).
> >
> > >> About 9% of voters have been removed from the pool. It is very
> >
> > possible
> >
> > >> that the result would have shifted if they had the opportunity to
> >
> > rank a
> >
> > >> 4th candidate, and therefore, it is possible that we won’t elect
> the
> >
> > >> person who truly represents the majority. Is this common? This is
> >
> > >> probably an abnormally close race. Thoughts?
> >
> > >>
> >
> > >> 2. What are your thoughts on London Breed’s response to being
> >
> > asked if
> >
> > >> RCV is fair? She stated “This is the system we are working with.
> >
> > That’s
> >
> > >> a discussion we can have at a later time. For now, we’re stuck
> >
> > with it.”
> >
> > >> - insinuating it is not fair. I was quite bothered to have a Dem
> in a
> >
> > >> progressive city insinuate that first past the post is more fair.
> It
> >
> > >> also felt divisive. If Leno wins, will her supporters feel that
> >
> > >> democracy prevailed, or that the election was stolen? She also
> >
> > presents
> >
> > >> herself as a minority candidate and it is my understanding that
> RCV
> >
> > >> gives minority candidates better chances and causes all
> >
> > candidates to be
> >
> > >> more likely to campaign to minority communities. Am I mistaken?
> Are
> >
> > >> there any legitimate arguments that FPTP can be more fair?
> Thoughts?
> >
> > >>
> >
> > >> Regards,
> >
> > >> —Chris
> >
> > >>
> >
> > >>
> >
> > >>
> >
> > >> ----
> >
> > >> Election-Methods mailing list - see http://electorama.com/em for
> >
> > list info
> >
> > >>
> >
> > > ----
> >
> > > Election-Methods mailing list - see http://electorama.com/em for
> >
> > list info
> >
> > >
> >
> >
> >
> > --
> >
> >
> >
> > r b-j rbj at audioimagination.com
> >
> > <mailto:rbj at audioimagination.com>
> >
> >
> >
> > "Imagination is more important than knowledge."
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > ----
> >
> > Election-Methods mailing list - see http://electorama.com/em for
> >
> > list info
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > --
> >
> > *Greg Dennis, Ph.D. :: Policy Director*
> >
> > Voter Choice Massachusetts
> >
> >
> >
> > e :: greg.dennis at voterchoicema.org <mailto:greg.dennis at voterchoicema.org
> >
> >
> > p :: 617.863.0746 <tel:617.863.0746>
> >
> > w :: voterchoicema.org <http://voterchoicema.org/>
> >
> >
> >
> > :: Follow us on Facebook
> >
> > <https://www.facebook.com/voterchoicema> and Twitter
> >
> > <https://twitter.com/voterchoicema> ::
> >
> >
> >
> >
> >
> > ----
> >
> > Election-Methods mailing list - see http://electorama.com/em for list
> info
> >
> >
> >
> >
> > ----
> >
> > Election-Methods mailing list - see http://electorama.com/em for list
> info
> >
> >
> > ----
> >
> > Election-Methods mailing list - see http://electorama.com/em for list
> info
> >
> >
> >
> >
> > ----
> >
> > Election-Methods mailing list - see http://electorama.com/em for list
> info
> >
> >
> >
> >
> > ----
> > Election-Methods mailing list - see http://electorama.com/em for list
> info
> >
>
> --
>
> r b-j rbj at audioimagination.com
>
> "Imagination is more important than knowledge."
>
>
>
>
>
>
>
> ----
> Election-Methods mailing list - see http://electorama.com/em for list info
>
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