[EM] TACC (total approval chain climbing) example

[C.Benham]

Kristofer,

> Is UMDT incompatible with mono-raise?

I don't know.

> Is UMDT incompatible with {mono-raise + Condorcet}?

Probably.

> If so, do you have a proof of this? 

No.

Chris Benham



On 4/22/2014 4:17 PM, Kristofer Munsterhjelm wrote:
> On 04/21/2014 11:39 PM, C.Benham wrote:
>> Forest,
>>
>>> 48 C
>>> 27 A>B
>>> 25 B
>>
>>> Borda, TACC, and IRV based methods like Woodall and Benham elect C.
>>>
>>> But Borda is clone dependent, and the IRV style elimination based
>>> methods fail monotonicity.  So TACC is a leading contender if we
>>> really take the Chicken Dilemma seriously.
>>
>> Benham and Woodall are a lot more resistant  to Burial than TACC (and
>> other Condorcet methods that meet mono-raise, aka monotonicity) because
>> they meet
>> "Unburiable Mutual Dominant Third" that says that if a set S of
>> candidates are all voted together on top of more than a third of the
>> ballots (i.e. on more than a third of the ballots no other candidates
>> are voted between or above them) and all the members of S pairwise beat
>> all the non-member candidates, then the winner X must come from S  (so
>> far the MDT criterion); and if some of the ballots that vote any Y above
>> X are altered by further lowering X then if the winner is changed it
>> can't be to Y.
>
> Is UMDT incompatible with mono-raise? Without thinking too much about 
> it, I'd expect some of the descending coalitions methods to pass it.
>
> Is UMDT incompatible with {mono-raise + Condorcet}? If so, do you have 
> a proof of this?
>