[EM] sequential dropping

[Markus Schulze]

Dear James Green-Armytage,

> Thank you Markus; that's good to know. However, I don't regard
> monotonicity to be an extremely important criterion.

However, I see the following problem: When someone promotes a
Condorcet method that violates monotonicity, then he cannot use
IRV's violation of this criterion as an argument against IRV.

*********

> I'm wondering: could you show an example with no pairwise ties
> where SD and beatpath give different results?

In situation 2 of my 12 July 2000 mail, beatpath chooses candidate F
while sequential dropping chooses candidate D. You can fill the
remaining pairwise defeats with arbitrarily chosen numbers. Then
this example could look e.g. as follows:

AB 21
BC 17
CD 15
DE 13
EF 18
FG 19
GA 14
DB 16
GE 20

AC  1
AD  2
AE  3
AF  4

BE  5
BF  6
BG  7

CE  8
CF  9
CG 10

DF 11
DG 12

Markus Schulze