[EM] Scott--BeatpathWinner & CSSD

Scott Ritchie scott at open-vote.org
Fri Jun 3 00:04:17 PDT 2005

On Fri, 2005-06-03 at 04:55 +0000, MIKE OSSIPOFF wrote:
> On Thu, 2005-06-02 at 05:40 +0000, MIKE OSSIPOFF wrote:
> >BeatpathWinner and CSSD, though they're equivalent, are completely
> >different algorithms
> You replied:
> what
> I reply:
> BeatpathfWinner and CSSD are two different count rules, implemented via 
> different algorithms.
> But they always give the same results as eachother, so they're said to be 
> equivalent.

If they're exactly equivalent, why even care about the less simple

f(x) = e^(2*ln (x)) and g(x) = x^2 are seemingly different algortihms,
yet they're exactly equivalent too - hence, they're actually the same
algorithm, and indeed the same function.

> Let me define them here:
> (snip)
> As I said, BeatpathWinner and CSSD always give the same result as eachother, 
> and so they're said to be equivalent.
> The BeatpathWinner algorithm is much simpler and briefer, but the CSSD 
> algorithm seems more naturally and obviously motivated and justified.
> I often refer to BeatpathWinner and CSSD as one method, by calling it 
> BeatpathWinner/CSSD. I've been recommending it for committees, 
> organizations, and meetings.

Forgive me for not using a 9 syllable phrase to describe something that
appears to be exactly equivalent to what's also being called Shulze's
method.  I don't mean to intrude on this contest you two seem to be in
(the internet, after all, is serious business), but for brevity's sake I
hope you don't mind if I use the term that might help with my

> I've been recommending SSD for public elections. In public elections, where 
> there are no pairwise ties, SSD and CSSD give the same results. In small 
> committees, SSD isn't clone-independent, and CSSD is. But in public 
> elections they both are.
> For public proposals, SSD is my favorite of the best wv methods, because its 
> definition doesn't refer to cycles or beatpaths, directly or indirectly. 
> There has been good reason to believe that that makes SSD more acceptable to 
> people.

Cool stuff.

> More recently I"ve heard tha MMPO meets FBC (with AERLO, it meets Strong 
> FBC). Also, MMPO is much briefer and simpler to define and propose, because 
> it doesn't need the list of preliminary definitions that the wv methods 
> need. So MMPO has become my favorite public proposal.
> I hadn't considered whether MMPO is a better proposal for committees, 
> organizations and meetings too, but it probably is. Especially since the 
> most valuable thing about electoral reform in committees, organizations and 
> meetings is that it provides experience and precedent for public proposals.
> Mike Ossipoff

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