Tideman Definition Different?

[David Marsay]

Mike may have been referring to my letter of 6 Jan 1998 'Re: 
Condorcet sub-cycle rule'.

I tend to regard variations on Condorcet as being more or less 
successful at defining the 'one true' method, not attempts to be 
distinctive. Thus I lump all there support together, while tending to 
ignore their flaws!

> From:          Mike Ositoff <ntk at netcom.com>
> Subject:       Tideman Definition Different?

> In the archives of this list, I ran across a letter which,
> if I remember correctly, quoted an article written or co-written
> by Tideman himself. The letter quoted a passage that defined
> Tideman's method (probably not calling it that).
> 
> The point of the person who posted the quoted passage was that
> the original definition didn't say to "skip" a defeat, and
> leave it skipped and ignored for the rest of the count, which
> is what the description in the _Journal of Economic Perspectives_
> article (Winter '95) seems to suggest doing.
> 
> The crucial phrase in the quotation was "...while preserving
> all pair orderings with greater majorities". As opposed to
> all greater defeats that haven't been skipped. So previously-
> skipped defeats _aren't_ subsequently ignored.
> 
> ***
> 
> So then, defined that way, Tideman's method wouldn't have the
> problem that I posted here a few days ago. Provided that
> it uses votes-against, I don't know that it has any problem
> that prevents it from being as good as EM's best. Admittedly,
> I don't know what it's properties are, though it does seem
> promising at first glance.
> 
> The person who posted the quoted passage also said that,
> when defined that way, Tideman is equivalent to Schulze. 
> Is that correct? I don't know which other method, if any,
> it's equivalent to.
> 
> But, if it is the same as Schulze, that's good, because
> it means that a method has been proposed in journal articles
> which (if modified to use votes-against) is the same as the
> best simple count rule we know of.
> 
> That's encouraging, just as it's encouraging that one of the
> academic authors had a guest-editorial published in the Washington
> Post, on June 21, '22, describing Plurality, IRO, Borda, &
> Condorcet, and saying that the aurhor preferred Condorcet.
> That's encouraging, because, with the use of votes-against,
> Condorcet is one of the best methods--even if better ones have
> now been found.
> 
> If it turns out that Tideman, by that better definition, 
> _isn't_ equivalent to one of our known best methods, it
> still appears promising. I don't want to appear to want to
> bash new methods that might be better. I welcome better ones,
> and if there's another one that's better than Smith//Condorcet(EM),
> then good--the more excellent methods the better.
> 
> Mike Ossipoff 
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