fsimm...@pcc.edu wrote:
As I remember it, when Toby settled on CSSD, we made a huge
psychological mistake: we got bogged down in the description of the
CSSD algorithm for the public proposal. I think that was a fatal
mistake, and I would like to propose a strategy for avoiding that
mistake in the future.
It was a mistake because it gave the impression that to understand
the proposal, you have to understand a detailed algorithm.
Here’s an analogy:
Complicated Version of the law of refraction: Snell’s law says that
the ratio of the signs of the angles of incidence and refraction are
equal to the ratios of the speeds of light in the respective media at
the interface where the refraction takes place. This is way too
technical for the average man on the street.
Simple version of the law of refraction: Fermat’s Principle's says
that light takes the path of least time. The man on the street can
understand this. Snell’s law gives a way of finding that path of
least time for the technician.
What is analogous to Fermat’s principle in the context of CSSD?
Answer: the beatpath winner idea. We elect the alternative A with
the strongest beatpaths to the other alternatives. This means that
for each alternative B, alternative A has a stronger beatpath to B
than B does to A. Once the concept of a beatpath is explained (and
that its strength is that of the weakest link) then the man on the
street can understand this definition of the method. The CSSD
algorithm is the technical part like Snell’s law,that the man on the
street doesn’t have to worry about.
So perhaps something like:
An indirect defeat of B by A is one where A beats B, or A beats someone
who indirectly beats B. An indirect defeat is a chain made of direct
defeats, each of whose strength is equal to the number of voters
preferring the winner. The strength of the indirect defeat itself is
equal to the strength of the link of least value[1].
When direct defeats contradict themselves, indirect defeats give a claim
as to whether one candidate is better than another. Therefore:
Elect the candidate that, no matter what other candidate you compare it
to, the former more strongly indirectly defeats the latter than vice versa.
-
It could be interesting to try to make short descriptions of various
Condorcet methods. The above is quite a bit longer than descriptions of,
say, Minmax or FPC, but the Schulze method also passes criteria the
other two don't.
[1] Or perhaps "closest to being overturned". Should one mention that if
there are more than one such chain, the strongest one counts?
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