[EM] Catchpoles RC fails your IIAC

Markus Schulze markus.schulze at alumni.tu-berlin.de
Thu Jan 24 02:22:52 PST 2002

Dear Mike,

you wrote (24 Jan 2002):
> Markus wrote (21 Jan 2002):
> > It seems that you don't know what "e.g." means.
> > "E.g." means "exempli gratia" ("for example").
> Shouldn't that be "exempli gratiae", if we want the "for"
> to be expressed?

Nope! "Gratia" is already ablativus.


You wrote (24 Jan 2002):
> What you'd said was irrelevant, because I didn't say that you
> were wrong about RC passing IIAC because RC isn't a voting
> system. I merely said that RC isn't a voting system. That's
> something that I said last time, and which you seem to have
> missed.

The fact that you don't consider Random Candidate to be a
"voting system" doesn't mean that we have to stop doing
everything. When people still discuss methods and criteria,
then this doesn't mean that they "have missed" what you said
sometime or that everything they discuss was "irrelevant".


You wrote (24 Jan 2002):
> Say there are 2 voters who, being used to Plurality, believe that
> they need to move a pre-existing lesser-evil candidate up to 1st
> place when the new candidate is added. Before the new candidate is
> added, there were 2 candidates, and those lesser-of-2-evils voters
> had voted for X. When the new candidate, Z, is addedd, Z is their
> last choice. They think Y has a better chance of beating Z, and so,
> they move that lesser-evil Y up to 1st place.
> Y had previously lost to X by one vote. Y pairbeats Z. Due to
> how those 2 voters change their votes when Z is added, Y becomes
> BeatsAll winner. Other voters don't change how they vote between
> X & Y.
> Before Z is added, X pair-beats Y and is BeatsAll winner. At that
> time, Y's probability of winning is 1/3. But when we add Z, now
> Y's probability of winning is 2/4, because those lesser-of-2-evils
> voters have made Y into BeatsAll winner.
> Adding the new candidate has increased Y's probability of winning,
> given the voting strategy of those lesser-of-2-evils voters.
> David Catchpole's RC fails your IIAC.

Your example only suggests that David Catchpole's Random Candidate
is vulnerable to strategical voting. But it doesn't demonstrate that
it is vulnerable to strategical nomination.

Markus Schulze

More information about the Election-Methods mailing list