On 11/11/2022 20:49, Forest Simmons wrote:
Since almost all RCV implementations limit the number of candidates
that can be ranked on a ballot, the simplest decent RCV method is ...
Elect the uncovered candidate that is unranked on the fewest ballot
Does anyone know why this truncation is imposed? If it’s to limit the
amount of work needed to count the ballots, wouldn’t it make sense for
Condorcet supporters to advocate a method which was countable in linear
time? In practice this would presumably be Sequential Pairwise
Elimination with an FPTP pre-ranking. If you insist on a quadratic time
method and accept the corollary of ballot truncation, I don’t imagine it
will work very well. Or am I missing something?
CJC
Evidently the IRV proposers hacve had to settle for ránking only there or
tour candidateson each ballot ... better than nothing.
One pass through the ballots to get the pairwise information and the number
of truncations for each candidate ... the exact same work as the SPE method
you propose ... but an agenda of first place votes breeds lots of vote
splitting unless you expect the voters to have lots of equal first rankings
... not a good idea.
Electing the uncovered candidate unranked on the fewest ballots is a
simpler Condorcet method than SPE ... and it is guaranteed to elect an
uncovered member of the Smith Set.
But SPE is also good ... if the agenda is clone independent, like implicit
approval.
-Forest
On Fri, Nov 11, 2022, 5:26 PM Colin Champion colin.champion@routemaster.app
wrote:
On 11/11/2022 20:49, Forest Simmons wrote:
Since almost all RCV implementations limit the number of candidates
that can be ranked on a ballot, the simplest decent RCV method is ...
Elect the uncovered candidate that is unranked on the fewest ballot
Does anyone know why this truncation is imposed? If it’s to limit the
amount of work needed to count the ballots, wouldn’t it make sense for
Condorcet supporters to advocate a method which was countable in linear
time? In practice this would presumably be Sequential Pairwise
Elimination with an FPTP pre-ranking. If you insist on a quadratic time
method and accept the corollary of ballot truncation, I don’t imagine it
will work very well. Or am I missing something?
Election-Methods mailing list - see https://electorama.com/em for list
info
I cannot comment on all implementations, but I do know that when STV-PR (RCV) was introduced for City council elections in Minneapolis a few years ago, voters were restricted to marking only three preferences because the tally machines used in the precincts for the precinct counts could tally only three columns.
James Gilmour
Edinburgh, Scotland
-----Original Message-----
From: Election-Methods [mailto:election-methods-
bounces@lists.electorama.com] On Behalf Of Colin Champion
Sent: Saturday, November 12, 2022 2:26 AM
To: election-methods@lists.electorama.com
Subject: Re: [EM] Easy fix to Alaska's ranked-choice voting
On 11/11/2022 20:49, Forest Simmons wrote:
Since almost all RCV implementations limit the number of candidates
that can be ranked on a ballot, the simplest decent RCV method is ...
Elect the uncovered candidate that is unranked on the fewest ballot
Does anyone know why this truncation is imposed? If it's to limit the amount
of work needed to count the ballots, wouldn't t it make sense for Condorcet
supporters to advocate a method which was countable in linear time? In
practice this would presumably be Sequential Pairwise Elimination with an
FPTP pre-ranking. If you insist on a quadratic time method and accept the
corollary of ballot truncation, I don t imagine it will work very well. Or am I
missing something?
Election-Methods mailing list - see https://electorama.com/em for list info
On 12.11.2022 02:26, Colin Champion wrote:
On 11/11/2022 20:49, Forest Simmons wrote:
Since almost all RCV implementations limit the number of candidates
that can be ranked on a ballot, the simplest decent RCV method is ...
Elect the uncovered candidate that is unranked on the fewest ballot
Does anyone know why this truncation is imposed? If it’s to limit the
amount of work needed to count the ballots, wouldn’t it make sense for
Condorcet supporters to advocate a method which was countable in linear
time? In practice this would presumably be Sequential Pairwise
Elimination with an FPTP pre-ranking. If you insist on a quadratic time
method and accept the corollary of ballot truncation, I don’t imagine it
will work very well. Or am I missing something?
Forced ballot truncation clearly makes every voting method fail clone
independence, so no, it's not just you.
As an extension of my Friendly Cover/Voting caveat (where it's difficult
to call a winner because first preferences are all distributed among
nobodies), forced ballot truncation probably also implies ISDA failure.
Perhaps even Smith failure, or Condorcet in pathological cases.
-km
Dare I say this easy fix needs a little "lateral thinking." I wrote of the monarchic hang-over, because single members offer the least choice of representation and present the greatest desire for rejection. (HG Wells, 1912: We no longer have elections, only Rejections. -- Like Hilary and Donald.) More seats per district make election more important than rejection; exclusion becomes less important with STV/PR in multi-member districts.
So, it doesn't matter that STV/PR has an irrational exclusion count, a sort of Last Past The Post exclusion procedure. A good century of experience shows that large majorities of first preferences get elected. Even in Ireland after the seat numbers were whittled down by the largest party to over-represent itself, perhaps two-thirds the voters would elect their first preferences, and high order preferences elect the rest.
My suggested Senate two-member STV/PR was only a step in the right direction (easy fix) within the constraints of the Senate two-member system. Except for Hawaii 50, sibling states could pair into 4-member districts, which would be tolerably democratic.
There are two issues to this easy fix. A single-member district is as much a rejection as an election, and a rejection cannot be an election. Hence, go to STV/PR.
The worlds election systems do not have a rational exclusion count. Binomial STV remedies that defect, even in single-member districts, but single-member districts are "only half a democracy" (Robert Newland).
Regards,
Richard Lung.
Re below: They should have had you, there, James!
[from James Gilmour]
I cannot comment on all implementations, but I do know that when STV-PR (RCV) was introduced for City council elections in Minneapolis a few years ago, voters were restricted to marking only three preferences because the tally machines used in the precincts for the precinct counts could tally only three columns.
James Gilmour
Edinburgh, Scotland
On 12 Nov 2022, at 12:16 pm, Kristofer Munsterhjelm km_elmet@t-online.de wrote:
On 12.11.2022 02:26, Colin Champion wrote:
On 11/11/2022 20:49, Forest Simmons wrote:
Since almost all RCV implementations limit the number of candidates that can be ranked on a ballot, the simplest decent RCV method is ... Elect the uncovered candidate that is unranked on the fewest ballot
Does anyone know why this truncation is imposed? If it’s to limit the amount of work needed to count the ballots, wouldn’t it make sense for Condorcet supporters to advocate a method which was countable in linear time? In practice this would presumably be Sequential Pairwise Elimination with an FPTP pre-ranking. If you insist on a quadratic time method and accept the corollary of ballot truncation, I don’t imagine it will work very well. Or am I missing something?
Forced ballot truncation clearly makes every voting method fail clone independence, so no, it's not just you.
As an extension of my Friendly Cover/Voting caveat (where it's difficult to call a winner because first preferences are all distributed among nobodies), forced ballot truncation probably also implies ISDA failure. Perhaps even Smith failure, or Condorcet in pathological cases.
Election-Methods mailing list - see https://electorama.com/em for list info
Q&D was the simplest way to always get the same result (when the Smith set
was four or fewer members) as Implicit Approval Chain Climbing ... a
monotonic, clone free, burial resistant, Banks efficient method ... as
simple as possible for a method with those criteria compliances ....
compliances that no other method on record could truthfully claim.
So why did it get no traction?
According guys "in the trenches" it has to be an elimination method with
vote transfers between steps.
No such method is monotonic, but the next best thing is Yee/Bolson
monotonic.
That method is Gross Loser Elimination (GLE).
The Gross Loser of a Round Robin tournament is the player whose worst score
(for any of her matchups) is worse than anybody elses's ... we could call
her the MinMin loser.
GLM is the elimination method that at each stage eliminates the gross loser
of the remaing candidates ... after the gross losers from the previous
stages have already been removed. The last candidate standing is the
winner.
As a reminder, the gross loser is the candidate with the worst worst score.
Each candidate has several scores ... one against each of the other
players. The worst of these is that candidate's worst score. The candidate
whose worst score is worse than anybody elses's worst score is the gross
loser. That is the one to be eliminated in the first step.
In the second step each candidate has a worst score in any of its matchups
with the remaining candidates. The candidate whose worst score is worse
than any other remaining candidate's worst score is the gross loser of that
stage. That's the one to be eliminated at that stage.
For example suppose that in 10th stage there are only four candidates left
... candidates A B,C,&D with respective worst matchup scores of 15, 13, 28,
and 35. Which one do you think would be eliminated at that stage?
If you guessed candidate B, you guessed right: B's worst score (13) at this
stage is worse (smaller than) any of the other three scores 15, 28, or 35.
Each elimination step is that simple!
Where do the matchup scores come from? In a sports tournament it is obvious
because each matchup is a completion for points.
In an election each matchup is also a competition for points ... in the
form of ........ (you guessed it) votes!
The scores we've been talking about are the votes in the head-to-head
matchups.
The beauty of RCV ballots is that for each matchup you can figure out the
scores for both candidates from the RCV ballots.
Suppose the matchup in question is between candidates X and Y.
Separate the ballots into three stacks.
Pretend that all of the other candidates are out of the picture so that all
votes are transferred to X and Y. How many votes would X get? That is X's
score for this matchup.
You don't have to actually deface the ballots by crossing out the
irrelevant candidates to find X's vote totals. Just count the number of
ballots on which candidate X outranks candidate Y.
This can be done for each of X's matchups, giving a complete set of matchup
scores for X.
Similarly we can get a completes set of matchup scores for each of the
other candidates.
And the one whose worst score is worse than anybody elses's worst score is
the Gross Loser.
So, to recap the method ... in the very first step eliminate the Gross
Loser. In the next step eliminate the Gross Loser from among the remaining
candidates, those who were not eliminated in the first step.
In all subsequent steps where more than two candidates remain, eliminate
the Gross Loser from among those remaining candidates.
When it gets down to two candidates eliminate the Gross Loser, the one
with the lowest score, i.e. the one with the fewest votes, i.e. elect the
one with the most votes in this final matchup.
This spells it out as plainly as I can do in the abstract. But what we all
know is children do not learn how to play a game by reading the
instructions on the inside cover of the box. They learn by playing with
friends who already know the rules.
This little card game (ballot counting game) is much simpler than Monopoly,
Poker, Uno, Clue, etc that kids feel pretty confident with after a couple
of dry runs with their friends.
A YouTube video is the second best way to teach it.
An EM text message is the worst way to teach it ... but you guys pick
things up faster than average!
-Forest
On Thu, Nov 10, 2022, 9:07 AM Toby Pereira tdp201b@yahoo.co.uk wrote:
So do you have a nice and simple definition of this method that anyone can
understand?
Where do you now stand on your Quick and Clean Burial Resistant Smith
method? At the time, it seemed to be the best thing since sliced bread, but
amongst all the posts, it now it appears not to have resisted, er, burial.
Toby
On Wednesday, 9 November 2022 at 22:07:53 GMT, Forest Simmons <
forest.simmons21@gmail.com> wrote:
I forgot to mention that Gross Loser Elimination is just as burial
resistant and Chicken resistant as IRV, and is less susceptible to
compromise than IRV, because unlike IRV, it has no Central Squeeze
pathology.
Imagine candidates X and Y close to the left and right of Center Z. Under
sincere ranked ballots Z will have few first choice votes compared to X and
Y, so it will be eliminated, unless one of the factions compromises and
votes its second choice Z over its favorite.
Which one would benefit by that insincere order reversal?
Answer: the pairwise loser in the final runoff step between X and Y.
A note on counting GLE.... a rectangular table of pairwise counts is
projected on the screen in the public counting room.
The k_th entry in the j_th row of the table is the number of ballots on
which the j_th candidate out ranks the k_th candidate.
As the ballots are opened and the candidate rankings carefully compared
one-by-one, the respective table entries for row j are incremental for each
candidate k that candidate j outranks on that ballot.
When the ballots have been fully tabulated, the elimination steps begin.
At each step the smallest entry in the table is circled. All viewers must
agree that it is indeed the smallest entry before continuing the step.
Once all observers are in agreement that the smallest entry is the k_th
entry of row j, then candidate j is declared to be the Gross Loser of this
step, and so is eliminated by crossing out both the j_th row and the j_th
column of the table.
The remaining table has one fewer row and one fewer column.
Find the Gross Loser of this smaller table by identifying which row has
the smallest entry, etc.
The last candidate standing is the GLE winner.
If you want the frosting on the cake, have a representative for each
candidate announce if they claim to have the highest uncovered candidate in
the finish order.
Process these claims in the reverse order, beginning with the GLE winner,
then the runner up, etc until either a claim is verified, or all have been
checked and refuted.
To check a claim X, those who challenge X must produce a candidate Y who
beats X, but is not at the end of a two step beat path from X to Y.
If the challengers cannot successfully refute the claim in this manner,
then the claim stands approved, and X is the winner.
In other words, elect the candidate with the first unrefutted claim in the
order of claim processing ... which (as we have already specified) is the
reverse of the elimination order.
Anybody have a better suggestion?
Nobody?
OK, then...how do we get the proposal ball rolling?
-Forest
On Wed, Nov 9, 2022, 8:50 AM Forest Simmons forest.simmons21@gmail.com
wrote:
This same simple tweak works on any method with a built in finish order,
including any one-at-a-time elimination method like IRV, BTR-IRV, Baldwin,
etc:
Elect the uncovered candidate highest in the finish order.
Why does our suggested tweak say to elect the highest uncovered candidate
in the finish order, instead of the highest unbeaten candidate in the
finish order?
Answer: because sometimes there is no unbeaten candidate, but there is
always an uncovered candidate.
The simplest and best one-by-one elimination method is Gross Loser
Elimination.
No other one-at-time elimination method can improve on it, much less the
uncovered version:
Elect the uncovered candidate highest in the Gross Elimination finish
order.
Like IRV it is clone free. Unlike IRV it is precinct summable on one pass
through the ballots at each precinct.
Wouldn't that have been nice last night at the midterm election count?
Like IRV it is non monotonic, but unlike IRV it is Yee/Bolson monotonic:
the win regions are convex, not pathological fractals. [I almost wrote
Bolsonaro instead of Bolson ... sorry Brian!]
Pick any method X, and pair it with Gross Loser Elimination ... uncovered
version or not ... and do a pairwise runoff between the two winners.
Not only will Gross Loser Elimination almost always come out ahead, the
people who do the experiment will come away saying, "Why do we even bother
with method X? GLE is so much more simple and effective."
GLE is already Smith efficient without the uncovered tweak ... that's just
optional frosting on the cake.
It is the simplest Smith efficient method that does not require computing
pairwise wins or losses. No need to mention Smith or Condorcet or pairwise
defeats.
It automatically eliminates the Condorcet Loser at any stage when there is
one, because when there is a Condorcet Loser, it will also be the Gross
Loser.
The Gross Loser is the candidate with the fewest ballots preferring it
over any other candidate. In a tournament, it is the candidate with the
single most embarrassingly low score.
In fact, unlike IRV, Gross Loser Elimination can be used to get a finish
order for a Round Robin Tournament, so the uncovered tweak can be applied
to it if so desired.
Suppose when there are only three uneliminated teams, team Rock's scores
against the other two teams stand at 60 and 40, while team Paper's scores
are 45 points against one team, and 72 against the other, and finally team
Scissors' scores stand at 35 and 90.
Which team will be eliminated at this stage of GLE?
Answer ... Scissors, because no other team scored as low as 35.
Note that we did not even need to know who the other team was that skunked
Scissors, or how much it scored in that game to know that Scissors was the
Gross Loser of that round.
Now tell me, who was the IRV loser of that round?
Answer: impossible to know, because IRV makes no sense in a tournament
context, unless it is a superficial popularity contest of some kind.
Is this the best RCV public proposal?
No other Universal Domain method this simple is anywhere near as good.
How about outside the UD? Do you think STAR is a better proposal? If so
why?
-Forest
On Wed, Nov 9, 2022, 12:05 AM Forest Simmons forest.simmons21@gmail.com
wrote:
In this context the most relevant question is what do we mean by
"uncovered", since that's the word used in the method definition ...
Repeatedly eliminate the (remaining) candidate with fewest votes until
there remains only one uncovered candidate to elect.
No need to know what covering means, although you can figure it out
indirectly from the definition of "uncovered:"
A candidate is uncovered iff it has a beatpath of only two steps to each
candidate (if any) that beats it.
Any candidate X who complains that they should have won because they beat
the winner W pairwise will get this truthful and obviously relevant
rejoinder:
When you were eliminated, you had fewer transferred votes than I.
I fact, I beat every candidate pairwise that was not already eliminated
(like you) on the basis of two few (transferred) votes.
It is very easy to discern if some candidate X is uncovered:
Just check each candidate Y that beats it (X) to see if it has a two step
beatpath via some Z, back to Y:
X beats Z beats Y
Only Smith candidates can be uncovered because only Smith candidates have
beatpaths back to the candidates that beat them. So the candidates you have
to check are the Smith candidates ... at most three, and rarely more than
one, in a public election.
If you want, you can run IRV all the way through ... then if the IRV
winner is uncovered, you are done. If not, back up until you cone to an
uncovered candidate ... that's your winner!
It's just a matter of doing regular IRV, and backing up (if necessary)
until you get to an uncovered candidate.
Forest
On Tue, Nov 8, 2022, 11:18 AM Kristofer Munsterhjelm km_elmet@t-online.de
wrote:
On 08.11.2022 18:02, Richard, the VoteFair guy wrote:
Forest, what do you mean by "covered"? Is there a Wikipedia or
Electowiki article (or section of an article) that explains it? Or is
there a dictionary reference you can point to?
Yes, you've used the words "covered" and "uncovered" many times but I
don't recall ever seeing a clear explanation of what you mean. I
presume it involves pairwise counts, but that's as far as I can guess.
The short answer is: A covers B if A pairwise beats everybody B pairwise
beats and then some.
An uncovered candidate is someone who is not covered by anyone else.
This definition works when there are no pairwise ties. Things get
trickier with pairwise ties, as I found out when generalizing Friendly
Cover.
Election-Methods mailing list - see https://electorama.com/em for list
info
Election-Methods mailing list - see https://electorama.com/em for list
info
Ken Bearman (who is unable to post to this list) sent some further info:
"At least here in Minneapolis and doubtless the other MN cities using
IRV/STV, too, I believe the limit on the number of candidates a voter
can rank is due to software limitations. There's also the issue of
certification of hardware. I don't know why nothing has progressed here
on those things."
He adds: "I've never learned exactly which level of government
(city, count, or state) has to do the work to get anything certified."
CJC
On 11/12/22 21:13, Forest Simmons wrote:
Q&D was the simplest way to always get the same result (when the Smith
set was four or fewer members) as Implicit Approval Chain Climbing ... a
monotonic, clone free, burial resistant, Banks efficient method ... as
simple as possible for a method with those criteria compliances ....
compliances that no other method on record could truthfully claim.
So why did it get no traction?
According guys "in the trenches" it has to be an elimination method with
vote transfers between steps.
No such method is monotonic, but the next best thing is Yee/Bolson
monotonic.
Just for fun, here's an elimination method that's monotonic:
Let the score in favor of A be A's number of first preferences after all
but one other candidate is eliminated in such a way as to maximize this
score.
Elect the candidate with greatest score in favor.
Of course, this is just maxmax in disguise (elect the candidate whose
greatest pairwise victory is greatest). But it's a fun joke :-)
A more difficult question: suppose that at no point is eliminating the
current first preference winner allowed - i.e. the chain of eliminations
can't eliminate, from a round, the pairwise winner of that round. Is the
method still monotone? (I think so, but I'm not sure.)
Or if only below-average fpp candidates can be eliminated - vaguely
reminiscent of Carey?
-km
(I'm creating a new thread title because Forest is using the previous
title for a different purpose.)
On 11/11/2022 5:26 PM, Colin Champion wrote:
Does anyone know why this truncation is imposed?
I suspect it's because the director of the FairVote organization (Rob
Richie) doesn't realize it's easy to count multiple marks in the same
"choice" column. He may be thinking that since he hasn't seen it done
that it can't be done.
Or he might assume the only way to do it would involve fractions or
decimal numbers. Yet of course that's not needed.
Here's a simple way to explain how to count multiple marks in the same
"choice" column without using fractions or decimal numbers:
When the counting reaches two ballots that top-rank the same two
remaining candidates, one of those two ballots is transferred to one of
the two candidates, and the other ballot is transferred to the other
candidate. This approach also works with a larger number of top-ranked
candidates.
The following code demonstrates the details of how this counting is done.
https://github.com/cpsolver/VoteFair-ranking-cpp/blob/master/rcipe_stv.cpp
Here are some relevant comments from this code:
// For all these calculations, ballots on which a
// voter marks more than one candidate at the
// same preference level are counted instead of
// being discarded.
//
// When shared preference levels are encountered,
// the ballots are transfered in "whole" numbers,
// not by splitting a ballot into fractional or
// decimal portions. For example, during a
// counting cycle, if there are two ballots that
// rank candidates numbered 1 and 2 at the same
// highest ranking level, one of the ballots will
// transfer to candidate 1 and the other ballot
// will transfer to candidate 2.
If you care about the algorithm, you can think of it this way: A ballot
that's transferred to candidate 1 goes into array position 1, ..., a
ballot for candidate 12 goes into array position 12, a ballot equally
marked for both candidate 11 and candidate 12 goes into array position
1112, a ballot equally marked for candidates 7, 14, and 23 goes into
array position 071423, etc. (The sequence of candidate numbers in the
encoded number has to be consistent.)
In the real code, instead of multiplying by 100 for each offset, a
smaller number is used. On this basis, as I recall, a 16-bit integer
can hold up to five equal-ranked candidates. If there are more than
five, that voter deserves to have their ballot ignored until only five
of their equal-ranked candidates remain (after elimination).
(Earlier we had a discussion in which we concluded that even though IRV
data is not precinct summable, it can be compressed and transmitted so
fast that there is no excuse for claiming the extra marks would take too
long to upload to the central counting location.)
It continues to surprise me that the FairVote-promoted "RCV" (IRV and
STV) certified software is so primitive.
For example, that software discards a ballot the moment the counting
detects multiple marks in the same choice column -- even if all but one
of those marks are for candidates who have already been eliminated!
FairVote terminology refers to an "overvote" as if it's a voter mistake
to mark multiple candidates at the same choice level.
Yet ranking multiple candidates at the same choice level is NOT a voter
mistake!!! It's a software designer's mistake!
Let's fix it for the benefit of the many more voters who will soon be
marking ranked choice ballots.
It's much easier to "teach" software to count any ballot marking pattern
than to teach voters to constrain their marks to what some poorly
designed, primitive software is capable of counting.
Richard Fobes
On 11/11/2022 5:26 PM, Colin Champion wrote:
On 11/11/2022 20:49, Forest Simmons wrote:
Since almost all RCV implementations limit the number of candidates
that can be ranked on a ballot, the simplest decent RCV method is ...
Elect the uncovered candidate that is unranked on the fewest ballot
Does anyone know why this truncation is imposed? If it’s to limit the
amount of work needed to count the ballots, wouldn’t it make sense for
Condorcet supporters to advocate a method which was countable in linear
time? In practice this would presumably be Sequential Pairwise
Elimination with an FPTP pre-ranking. If you insist on a quadratic time
method and accept the corollary of ballot truncation, I don’t imagine it
will work very well. Or am I missing something?
Election-Methods mailing list - see https://electorama.com/em for list info
I tried to state the most understandable description possible of Gross
Loser Elimination ... is the following version an improvement? Anybody have
a simpler or clearer description?
Suppose there are seven candidates. Each candidate gets six cards with
their name at the top and one of the other candidate names just below it.
Each card is given to a different election worker.
Pretend you are in charge of the card with Diane at the top and Jenny just
below it.
As the ballots are slowly opened one by one in a public ceremony so that
everybody can see each ballot on an overhead projector screen, you put a
hash mark on your Diane/Jenny card every time a ballot is opened that shows
a vote for Diane over Jenny.
After the ballots have been tallied in this way, you total the votes, and
put that vote total to the left of her name on the top left of your card.
This is the total of her votes in her matchup against one of the other
candidates, namely Jenny.
Then you hand in your card to the head vote counter, who sorts the cards in
order of the vote totals in the upper left corner of each card.
Now the Elimination steps:
Remove the card from the bottom of the stack, the one with the smallest
vote total next to the name at the top of that card. That name identifies
the Gross Loser. Eliminate all of the cards that have that name anywhere on
it. That concludes one step of GLE, Gross Loser Elimination.
Now remove the card from the bottom of the remaining deck. The name at the
top of that card is the Gross Loser name for this step.. Eliminate all of
the cards that have that name anywhere on it. That concludes another step
of GLE, Gross Loser Elimination.
Now remove the card from the bottom of the remaining deck. The name at the
top of that card is the Gross Loser name for this step.. Eliminate all of
the cards that have that name anywhere on it. That concludes another step
of GLE, Gross Loser Elimination.
Continue in this manner until all cards but two have been eliminated.
Eliminate the bottom of these two, and elect the candidate whose name is at
the top of the remaining card. This is the only candidate that was never at
any stage the worst of the worst ... i.e. never the Gross Loser.
-Forest
On Sat, Nov 12, 2022, 12:13 PM Forest Simmons forest.simmons21@gmail.com
wrote:
Q&D was the simplest way to always get the same result (when the Smith set
was four or fewer members) as Implicit Approval Chain Climbing ... a
monotonic, clone free, burial resistant, Banks efficient method ... as
simple as possible for a method with those criteria compliances ....
compliances that no other method on record could truthfully claim.
So why did it get no traction?
According guys "in the trenches" it has to be an elimination method with
vote transfers between steps.
No such method is monotonic, but the next best thing is Yee/Bolson
monotonic.
That method is Gross Loser Elimination (GLE).
The Gross Loser of a Round Robin tournament is the player whose worst
score (for any of her matchups) is worse than anybody elses's ... we could
call her the MinMin loser.
GLM is the elimination method that at each stage eliminates the gross
loser of the remaing candidates ... after the gross losers from the
previous stages have already been removed. The last candidate standing is
the winner.
As a reminder, the gross loser is the candidate with the worst worst
score. Each candidate has several scores ... one against each of the other
players. The worst of these is that candidate's worst score. The candidate
whose worst score is worse than anybody elses's worst score is the gross
loser. That is the one to be eliminated in the first step.
In the second step each candidate has a worst score in any of its matchups
with the remaining candidates. The candidate whose worst score is worse
than any other remaining candidate's worst score is the gross loser of that
stage. That's the one to be eliminated at that stage.
For example suppose that in 10th stage there are only four candidates left
... candidates A B,C,&D with respective worst matchup scores of 15, 13, 28,
and 35. Which one do you think would be eliminated at that stage?
If you guessed candidate B, you guessed right: B's worst score (13) at
this stage is worse (smaller than) any of the other three scores 15, 28, or
35.
Each elimination step is that simple!
Where do the matchup scores come from? In a sports tournament it is
obvious because each matchup is a completion for points.
In an election each matchup is also a competition for points ... in the
form of ........ (you guessed it) votes!
The scores we've been talking about are the votes in the head-to-head
matchups.
The beauty of RCV ballots is that for each matchup you can figure out the
scores for both candidates from the RCV ballots.
Suppose the matchup in question is between candidates X and Y.
Separate the ballots into three stacks.
Pretend that all of the other candidates are out of the picture so that
all votes are transferred to X and Y. How many votes would X get? That is
X's score for this matchup.
You don't have to actually deface the ballots by crossing out the
irrelevant candidates to find X's vote totals. Just count the number of
ballots on which candidate X outranks candidate Y.
This can be done for each of X's matchups, giving a complete set of
matchup scores for X.
Similarly we can get a completes set of matchup scores for each of the
other candidates.
And the one whose worst score is worse than anybody elses's worst score is
the Gross Loser.
So, to recap the method ... in the very first step eliminate the Gross
Loser. In the next step eliminate the Gross Loser from among the remaining
candidates, those who were not eliminated in the first step.
In all subsequent steps where more than two candidates remain, eliminate
the Gross Loser from among those remaining candidates.
When it gets down to two candidates eliminate the Gross Loser, the one
with the lowest score, i.e. the one with the fewest votes, i.e. elect the
one with the most votes in this final matchup.
This spells it out as plainly as I can do in the abstract. But what we all
know is children do not learn how to play a game by reading the
instructions on the inside cover of the box. They learn by playing with
friends who already know the rules.
This little card game (ballot counting game) is much simpler than
Monopoly, Poker, Uno, Clue, etc that kids feel pretty confident with after
a couple of dry runs with their friends.
A YouTube video is the second best way to teach it.
An EM text message is the worst way to teach it ... but you guys pick
things up faster than average!
-Forest
On Thu, Nov 10, 2022, 9:07 AM Toby Pereira tdp201b@yahoo.co.uk wrote:
So do you have a nice and simple definition of this method that anyone
can understand?
Where do you now stand on your Quick and Clean Burial Resistant Smith
method? At the time, it seemed to be the best thing since sliced bread, but
amongst all the posts, it now it appears not to have resisted, er, burial.
Toby
On Wednesday, 9 November 2022 at 22:07:53 GMT, Forest Simmons <
forest.simmons21@gmail.com> wrote:
I forgot to mention that Gross Loser Elimination is just as burial
resistant and Chicken resistant as IRV, and is less susceptible to
compromise than IRV, because unlike IRV, it has no Central Squeeze
pathology.
Imagine candidates X and Y close to the left and right of Center Z.
Under sincere ranked ballots Z will have few first choice votes compared to
X and Y, so it will be eliminated, unless one of the factions compromises
and votes its second choice Z over its favorite.
Which one would benefit by that insincere order reversal?
Answer: the pairwise loser in the final runoff step between X and Y.
A note on counting GLE.... a rectangular table of pairwise counts is
projected on the screen in the public counting room.
The k_th entry in the j_th row of the table is the number of ballots on
which the j_th candidate out ranks the k_th candidate.
As the ballots are opened and the candidate rankings carefully compared
one-by-one, the respective table entries for row j are incremental for each
candidate k that candidate j outranks on that ballot.
When the ballots have been fully tabulated, the elimination steps begin.
At each step the smallest entry in the table is circled. All viewers must
agree that it is indeed the smallest entry before continuing the step.
Once all observers are in agreement that the smallest entry is the k_th
entry of row j, then candidate j is declared to be the Gross Loser of this
step, and so is eliminated by crossing out both the j_th row and the j_th
column of the table.
The remaining table has one fewer row and one fewer column.
Find the Gross Loser of this smaller table by identifying which row has
the smallest entry, etc.
The last candidate standing is the GLE winner.
If you want the frosting on the cake, have a representative for each
candidate announce if they claim to have the highest uncovered candidate in
the finish order.
Process these claims in the reverse order, beginning with the GLE winner,
then the runner up, etc until either a claim is verified, or all have been
checked and refuted.
To check a claim X, those who challenge X must produce a candidate Y who
beats X, but is not at the end of a two step beat path from X to Y.
If the challengers cannot successfully refute the claim in this manner,
then the claim stands approved, and X is the winner.
In other words, elect the candidate with the first unrefutted claim in
the order of claim processing ... which (as we have already specified) is
the reverse of the elimination order.
Anybody have a better suggestion?
Nobody?
OK, then...how do we get the proposal ball rolling?
-Forest
On Wed, Nov 9, 2022, 8:50 AM Forest Simmons forest.simmons21@gmail.com
wrote:
This same simple tweak works on any method with a built in finish order,
including any one-at-a-time elimination method like IRV, BTR-IRV, Baldwin,
etc:
Elect the uncovered candidate highest in the finish order.
Why does our suggested tweak say to elect the highest uncovered candidate
in the finish order, instead of the highest unbeaten candidate in the
finish order?
Answer: because sometimes there is no unbeaten candidate, but there is
always an uncovered candidate.
The simplest and best one-by-one elimination method is Gross Loser
Elimination.
No other one-at-time elimination method can improve on it, much less the
uncovered version:
Elect the uncovered candidate highest in the Gross Elimination finish
order.
Like IRV it is clone free. Unlike IRV it is precinct summable on one pass
through the ballots at each precinct.
Wouldn't that have been nice last night at the midterm election count?
Like IRV it is non monotonic, but unlike IRV it is Yee/Bolson monotonic:
the win regions are convex, not pathological fractals. [I almost wrote
Bolsonaro instead of Bolson ... sorry Brian!]
Pick any method X, and pair it with Gross Loser Elimination ... uncovered
version or not ... and do a pairwise runoff between the two winners.
Not only will Gross Loser Elimination almost always come out ahead, the
people who do the experiment will come away saying, "Why do we even bother
with method X? GLE is so much more simple and effective."
GLE is already Smith efficient without the uncovered tweak ... that's
just optional frosting on the cake.
It is the simplest Smith efficient method that does not require computing
pairwise wins or losses. No need to mention Smith or Condorcet or pairwise
defeats.
It automatically eliminates the Condorcet Loser at any stage when there
is one, because when there is a Condorcet Loser, it will also be the Gross
Loser.
The Gross Loser is the candidate with the fewest ballots preferring it
over any other candidate. In a tournament, it is the candidate with the
single most embarrassingly low score.
In fact, unlike IRV, Gross Loser Elimination can be used to get a finish
order for a Round Robin Tournament, so the uncovered tweak can be applied
to it if so desired.
Suppose when there are only three uneliminated teams, team Rock's scores
against the other two teams stand at 60 and 40, while team Paper's scores
are 45 points against one team, and 72 against the other, and finally team
Scissors' scores stand at 35 and 90.
Which team will be eliminated at this stage of GLE?
Answer ... Scissors, because no other team scored as low as 35.
Note that we did not even need to know who the other team was that
skunked Scissors, or how much it scored in that game to know that Scissors
was the Gross Loser of that round.
Now tell me, who was the IRV loser of that round?
Answer: impossible to know, because IRV makes no sense in a tournament
context, unless it is a superficial popularity contest of some kind.
Is this the best RCV public proposal?
No other Universal Domain method this simple is anywhere near as good.
How about outside the UD? Do you think STAR is a better proposal? If so
why?
-Forest
On Wed, Nov 9, 2022, 12:05 AM Forest Simmons forest.simmons21@gmail.com
wrote:
In this context the most relevant question is what do we mean by
"uncovered", since that's the word used in the method definition ...
Repeatedly eliminate the (remaining) candidate with fewest votes until
there remains only one uncovered candidate to elect.
No need to know what covering means, although you can figure it out
indirectly from the definition of "uncovered:"
A candidate is uncovered iff it has a beatpath of only two steps to each
candidate (if any) that beats it.
Any candidate X who complains that they should have won because they beat
the winner W pairwise will get this truthful and obviously relevant
rejoinder:
When you were eliminated, you had fewer transferred votes than I.
I fact, I beat every candidate pairwise that was not already eliminated
(like you) on the basis of two few (transferred) votes.
It is very easy to discern if some candidate X is uncovered:
Just check each candidate Y that beats it (X) to see if it has a two step
beatpath via some Z, back to Y:
X beats Z beats Y
Only Smith candidates can be uncovered because only Smith candidates have
beatpaths back to the candidates that beat them. So the candidates you have
to check are the Smith candidates ... at most three, and rarely more than
one, in a public election.
If you want, you can run IRV all the way through ... then if the IRV
winner is uncovered, you are done. If not, back up until you cone to an
uncovered candidate ... that's your winner!
It's just a matter of doing regular IRV, and backing up (if necessary)
until you get to an uncovered candidate.
Forest
On Tue, Nov 8, 2022, 11:18 AM Kristofer Munsterhjelm <
km_elmet@t-online.de> wrote:
On 08.11.2022 18:02, Richard, the VoteFair guy wrote:
Forest, what do you mean by "covered"? Is there a Wikipedia or
Electowiki article (or section of an article) that explains it? Or is
there a dictionary reference you can point to?
Yes, you've used the words "covered" and "uncovered" many times but I
don't recall ever seeing a clear explanation of what you mean. I
presume it involves pairwise counts, but that's as far as I can guess.
The short answer is: A covers B if A pairwise beats everybody B pairwise
beats and then some.
An uncovered candidate is someone who is not covered by anyone else.
This definition works when there are no pairwise ties. Things get
trickier with pairwise ties, as I found out when generalizing Friendly
Cover.
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