[EM] Criteria reply

Markus Schulze markus.schulze at alumni.tu-berlin.de
Wed May 18 02:46:45 PDT 2005


Dear Mike Ossipoff,

you wrote (18 May 2005):
> At that time I thought that BeatpathWinner was your method, not
> realizing at that time what "Schulze's method" actually means.
> And, as I said yesterday, and as I said last month, in reply to
> the same repeated statement, I, at that earlier time, carelessly
> said that SSD is equivalent to BeatpathWinner, because it's
> equivalent to BeatpathWinner when there are no pairwise
> ties. When there are pairwise ties, SSD is not equivalent to
> BeatpathWinner. CSSD is equivalent to BeatpathWinner, but SSD
> is not. I've admitted that error last month, and yesterday,
> but you keep repeating that quote. I knew of BeatpathWinner
> when I and Eppley devised SSD. I at that time thought that
> BeatpathWinner was you rmethod, because at that time I didn't
> realiize that, as you said last month,  "Schulze's method"
> means something different. I didn't know of your CSSD
> definition, because I hadn't read those postings, and didn't
> know what count rule they described. At that time I mistakenly
> believed that 'Schulze's method" meant the count rule that I
> call "BeatpathWinner". I've only explained that about five
> times in the last 24 hours, and at least a dozen times last
> month.

Well, although you have been pointed to this error dozens of
times in the last 5 years and although you have admitted this
error several times, you keep on using this error as an argument.

Russ Paielli proposed "Ranked Approval Voting" (RAV). Then he was
pointed to the fact that presumably this method had already been
proposed by Kevin Venzke. Russ Paielli immediately stopped claiming
that he had invented RAV. Russ Paielli didn't say something like:
"I hadn't read Kevin's proposal when I proposed RAV. Therefore,
I can rightly claim that I invented RAV."

On the other side, you keep on using your claim, that you hadn't
completely understood the Schulze method when you proposed SSD,
as an argument to claim that you "devised" SSD.

By the way: Already in 2001, Norman Petry complained that you try to
take credit for this method. He wrote (6 Feb 2001):

> Regardless of what names we use when referring to these methods during
> our committee discussions, I think it is appropriate that if one of
> these variants is recommended to Debian that it be named SCHULZE'S
> METHOD.  This is because:
>
> 1. Schulze, version 1: The 'Beat-Or-Tie-path' method was first proposed by
> Markus Schulze on Sat, 4 Oct 1997 (see EM Archives, "Re: Condorect sub-cycle
> rule").  Unfortunately, eGroups has not archived this message, but it can
> be found at Rob's site, in this text file (but mistakenly referred to there
> as "Tideman's Method"): http://www.eskimo.com/~robla/em/archive/em.97q4
>
> 2. Schulze, version 2: The 'Schwartz Sequential Dropping' (SSD) method was
> first proposed by Markus Schulze on Mon, 10 Aug 1998.  His description can
> be found here:
> http://groups.yahoo.com/group/election-methods-list/message/673
>
> 3. Schulze, version 3: The 'Cloneproof SSD' method was first proposed by
> Markus Schulze on Sat, 14 Nov 1998.  See:
> http://groups.yahoo.com/group/election-methods-list/message/2291  As noted
> above, Markus' version of 'Cloneproof SSD' uses a slightly different (and
> imo better) tiebreaker than Mike's version, but the two methods are
> otherwise identical.
>
> 4. Beatpath Winner: This was not specifically proposed by Markus Schulze,
> but it is equivalent in terms of results to Cloneproof SSD.  It is the
> same as 'Beat-or-tie-path' winner, except that pairties in the matrix are
> zeroed out before paths are computed, so that tied values cannot be part
> of the paths used to determine the winner.
>
> Since Markus was the originator of the first three of these methods, and
> usually refers to all of them as "Schulze's Method", it seems appropriate
> to name them as he has done.

************

You wrote (17 May 2005):
> Where did SSD come from? In individual e-mail, Steve Eppley suggested a
> method that successively drops the weakest defeat among the smallest set
> of candidates that is unbeaten from without. SSD is an Eppley-Ossipoff
> method.

I wrote (17 May 2005):
> Please forward this communication between Steve Eppley and you. I would
> like to know why (although you considered neither independence of clones
> nor reversal symmetry important and although Steve Eppley decided to
> promote Tideman's ranked pairs method) you decided to promote SSD.

You wrote (18 May 2005):
> I don't save e-mail back to those days. But my mention of SSD on EM is
> in the EM archives. That's really all you need.

Well, the very first time that the term "Schwartz Sequential Dropping"
(SSD) was being used was on 18 Feb 2000 in a mail by you. In that mail,
you wrote that "SSD is equivalent to Schulze's method". Actually, the
fact that "SSD is equivalent to Schulze's method" was your main argument
for proposing SSD. Therefore, the EM archives don't support your claim
that "SSD is an Eppley-Ossipoff method".

You wrote (18 May 2005):
> You ask why I decided to promote SSD. Because it's clone-independent
> in public elections, and because it meets SFC, GSFC, WDSC, and SDSC.

Nope. You didn't consider independence of clones important when you
proposed SSD. Nor did you mention clones in that mail.

************

You wrote (18 May 2005):
> You seem surprised that I'd promote SSD when Steve prefers MAM.
> Why do you expect me to copy Steve on that? Actually, Ranked-Pairs
> has a very brief definition, if we ignore the rules for equal defeats.
> But those equal defeat rules can't be completely left out. And RP's
> definition, directly or indirectly, mentions cycles. So I consider
> SSD to be a better public proposal.
>
> In the matter of SSD vs RP, in terms of pure merit, in public
> elections, RP might very well be _very slightly_ more aesthetically
> appealing, because RP, unlike BeatpathWinner, CSSD, or SSD, never
> lets a nullilfied defeat participate in the nullification of other
> defeats.
>
> But I consider the merit differences between RP and SSD completely
> negligible in public elections. That's where Steve and I disagree.
> What's wrong with disagreeing?

You want to know what's wrong with that? Well, on the one side
you claim that you are having quite productive discussions with
other people off-list. And on the other side, you neither forward
nor save such discussions. Do you have some kind of politics
like "discuss in a constructive manner only off-list"?

Markus Schulze



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