Kevin Venzke wrote:
Hi Kristofer,

Here's an attempt at a more concrete example:

A     3
ABCD  13
ACBD  1
ACDB  5
ADBC  5
BACD  16
B     3
BCDA  5
CDAB  20
DBCA  24
total 95

(...)

A does have two tied margins; I'm unsure if they make a difference, or
if it can be easily fixed if they do. But it doesn't seem like they
should make a difference (i.e. for checking Ext-Minmax) because those
margins are relatively weak.

I just checked it with my Ext-Minmax implementation, and it still works (that is, fails the criterion). The debug data I get from Ext-Minmax is:

For the first scenario:

After sorting: 0        6   6   1
After sorting: 1        16   0   0
After sorting: 3        31   0   0
After sorting: 2        40   0   0

For the second scenario:

After sorting: 0        8   0   0
After sorting: 1        9   0   0
After sorting: 3        31   1   0
After sorting: 2        47   1   0

Plain Minmax consistently elects A here, which is no problem for plain Minmax (or Ext-Minmax for that matter), but the Smith restriction causes trouble.

Back to the drawing board, I guess! Do you think the compliance could be salvaged by using Smith,Minmax(PO) instead -- or, more strictly, by disallowing trunaction? Either might lead closer to a method that passes Smith and mono-add-top...

Worse is the fact that my program didn't find a compliance disproof even though I now know there to be one. I'll have to find out why; one possibility is that the failures are exceedingly uncommon and it simply can't stumble upon one by brute force.
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