(Replying farther down)

On Oct 5, 2016 11:13 AM, "Markus Schulze" <
markus.schulze@alumni.tu-berlin.de> wrote:

(endquote )

The MAM winner has no defeats that aren't  nullified by being the weakest
defeat in a cycle whose other defeats are affirmed.

...and those affirmed stronger defeats are affirmed because that can't be
said of them.

Additionally, I remind you that our topic is MAM vs Schulze. Therefore the
pairwise comparison most relevant here is the pairwise comparison between
MAM & Schulze.    ...a comparison which MAM wins several times more often
than Schulze does.

Michael Ossipoff

http://lists.electorama.com/pipermail/election-methods-electorama.com/2000-November/069868.html

https://www.mail-archive.com/election-methods-list@eskimo.com/msg02310.html

https://groups.yahoo.com/neo/groups/election-methods-list/conversations/topics/5948

http://lists.electorama.com/pipermail/election-methods-electorama.com/2004-May/078166.html

https://groups.yahoo.com/neo/groups/election-methods-list/conversations/messages/14251

https://services.math.duke.edu/~bray/Courses/49s-GTD/Senior%20Theses/Barry%20Wright/Barry%20Wright's%20Thesis.pdf

Marcus,

In the 3-candidate case, how can "Least Worst Defeat" (aka MinMax ?) and
Schulze ever disagree?

As I understand it, Schulze and MAM  and  River and Smith//MinMax can
only ever give different winners when
there are more than three candidates in the Smith set.

That chance of that happening in a real public election is close enough
to zero, so therefore "MAM versus Shulze"
strikes me as pointless.

And if it didn't I wouldn't find the argument that one's winner pairwise
beats the other's a small proportion  of times more
than vice versa very compelling.

Chris Benham

On 10/6/2016 4:43 AM, Markus Schulze wrote:

No, it wasn't the polygamy poll that I looked at. It only has 5
alternatives.

It was one of the others. I don't know which one.

Michael Ossipoff
On Oct 6, 2016 9:33 AM, "Michael Ossipoff" email9648742@gmail.com wrote:

It was probably my 23-candidate, 19-party 2016 presidential poll.

By the way, without Bernie, Jill Stein is CWv, beating everyone by  a large
factor.

Trump finished at bottom among the original candidates (the two write-ins
were too recent to have a chance to get much support).

Jill beat Donald by a factor of several to one.

The lowest-finishing socialist best Trump by a factor of 2 to 1.

The lowest finishing socialist beat the highest-finishing Republican by a
factor of 1.5 to 1.

Sampling bias? With Jill finishing 1st & Donald finishing last, will you
say that sampling bias justifies saying that Trump might beat Stein in an
honest election with honest media? That would take rather a lot of sampling
bias.

:^)

...because only some have computers? People who have more money are known
to be more conservative.

Yes, some polls show Hillary beating Jill. In my poll, Hillary finished 5th.

Drastic differences like that must result from different electorates.
..the poll being announced to different people.

...to partisan organizations in particular.

My poll was announced only at the polling website (CIVS), and at Democracy
Chronicles.

...not to any partisan organizations.

Michael Ossipoff
On Oct 6, 2016 10:22 AM, "Michael Ossipoff" email9648742@gmail.com wrote:

Mike,

As far as I can tell, for all intents and purposes  MAM,  Schulze, River
and  Smith//MinMax (wv)  are all just different wordings
of the same method.

If you think that MAM  is better than Shulze, then what criterion (that
we might care about) is met by MAM and not Shulze?

Or perhaps you have some example in mind where you think the MAM winner
is much prettier than the Schulze  winner?

C: Is that definition fully adequate?  It doesn't tell you where to start.

C: Recently you accepted that  Winning Votes  is at best "maybe a bit
questionable", so why do you think that we should "propose" either?

If  you want a Condorcet method that meets  Chicken Dilemma then I
prefer both "Benham"  and  Losing Votes (erw) Sorted Margins Elimination.

If you want a method that (like WV) meets Minimal Defense then I prefer
Forest's  "Max Covered Approval"  (which would nearly always be equivalent
to Smith//Approval, which I also like.)

Chris  Benham

On 10/7/2016 3:03 AM, Michael Ossipoff wrote:

On 10/08/2016 03:06 PM, C.Benham wrote:

I'm not Mike (and I don't see his posts), but I would probably say LIIA
for MAM and IPDA/ISDA for River. Those criteria probably only become
relevant (that is, failed by Schulze) when the Smith set size is large,
however, so whether you consider them important would depend in part on
whether you think large Smith sets may occur in real elections. On the
one hand, they haven't so far; on the other, adoption of a Condorcet
method might lead to a richer political landscape where they could.

MAM and River may also be simpler to explain than Schulze, since a brief
description of beatpaths require recursion, and recursion is a tricky
concept to get if you haven't already been exposed to it.

How about, for MAM:

Sort defeats in order from strongest to weakest. Going from strongest to
weakest, affirm a defeat unless it forms a cycle with earlier affirmed
defeats. The candidate who isn't beaten in any affirmed defeat wins.

Schulze:

A has a beatpath to B if A beats B or A beats someone who has a beatpath
to B. The strength of a beatpath is defined by the strength of its
weakest defeat. The candidate who, for every other candidate has a
stronger beatpath to that candidate than that candidate has to him, wins.

Neither definition goes into the subtlety of tiebreakers (random voter
hierarchy for MAM) nor margins vs wv.

If you had to pick a method passing Minimal Defense but not using
Approval information, which would it be? (That is, do you have any
favorites in that category, and if so, which?)

On Oct 8, 2016 6:06 AM, "C.Benham" cbenham@adam.com.au wrote:

and  Smith//MinMax (wv)  are all just different wordings

No. They sometimes choose different winners.

we might care about) is met by MAM and not Shulze?

Sometimes they choose the same, sometimes they don't.

When they don't, the MAM winner is publicly preferred to the Schulze winner
several times more often than vice-versa.

(It seems to me that it might have been something like 4 to 1, or 5 to 1.
Steve Eppley would be the one to ask.)

So: Choose in keeping with public preference, or contrary to it. Your choice

MAM's brief, natural & obvious definition is the opposite of the arbitrary
definition of Schulze or CSSD.

MAM's definition clearly is the one that doesn't unnecessarily disregard a
defeat.

It disregards a defeat only it's the weakest in a cycle with defeats for
which there  isn't
justification to disregard them.

And, as I said, it's no surprise when unnecessarily disregarding defeats
results in a winner to whom the public prefer the MAM winner.

is much prettier than the Schulze  winner?

Publicly-preferred is prettier.

Minimally disregarding defeats only with obviousl, strong justification,
never unnecessarily disregarding a defeat--That's prettier.

other defeats are affirmed.

Yes.

You wrote:

It doesn't tell you where to start.

It isn't a procedural definition or a count-instruction. It's a brief
recursive definition.

Given a set of rankings, it fully and definitely specifies a set of
affirmed defeats, & a set of not-affirmed defeats.

...and fully specifies the winner.

For a procedure:

Write down the strongest defeat.

Below it, write down the next strongest defeat.

Below that, write down the next strongest defeat, if it doesn't cycle with
defeats already written down.

Repeat the paragraph before this one, until all the defeats have been
considered as described in that paragraph.

A candidate wins if s/he has no written-down defeats.

(end of count instruction)

propose the more complicatedly-worded, elaborately- worded one?

questionable", so why do you think that we should "propose" either?

(endquote)

I said they might be iffy or questionable. I didn't say they're ruled out.

For that questionable-ness, you get a chance for much better strategy.

...at the cost of the possibility of the strategic mess of the
perpetual-burial fiasco.

I'd say that MAM, Smith//MMPO, & plain MMPO are worth a try.

They should be included in a proposal that lists a number of suggested
methods.

In particular, for an unlimited-rankings method, Plain MMPO offers the
most, for current conditions.

both "Benham"  and  Losing Votes (erw) Sorted Margins Elimination.

(endquote)

They're far too vulnerable to truncation & burial.

In WV & MMPO, truncation just doesn't work. The CWs still wins.

The strategy situation of the methods you listed isn't as good as Bucklin.

Surely the purpose of a pairwise-count method is to improve on Bucklin.

In Bucklin & Approval, the CWs's preferrers can protect hir win by plumping.

In Benham, Woodall, & Margins-Sorted LV Elimination, the best they can do
is:

Say it's Worst (W), Middle (M), & Favorite (F).

M is the middle CWs.

The M voters could estimate or look up the expected sizes of the W & F
factions.  ...& rank one over the other probabilistically, so that each
one's probability of pair-beating the other is 50%.

...so that burial has a 50% chance of backfiring.

In Bucklin, WV or MMPO, they need merely to plump.

Or the F voters could rank M alone in 1st place. That would work in IRV too
(nothing else would).

As I said, surely the purpose of a pairwise-count method is to improve on
Bucklin.

Forest's  "Max Covered Approval"  (which would nearly always be equivalent

Smith//Approval shares the great vulnerability to truncation & burial.

Michael Ossipoff

larger Smith set.

fails MAM's criteria will never happen.

people in Burlington.

than 3 candidates, that we speak of how MAM & Schulze differ.

propose the more complicatedly-worded, elaborately- worded one?

other defeats are affirmed.

farther down in the finishing order.

laws for bigamy.

cycle was far down in the finishing order).

assumption doesn't hold for low finishing positions.