[EM] "Unmanipulable Majority" strategy criterion

[Kevin Venzke]

Hi Chris,

--- En date de : Mer 26.11.08, Chris Benham <cbenhamau at yahoo.com.au> a écrit :
I have a suggestion for a new strategy criterion I might call  
"Unmanipulable Majority".
 
*If (assuming there are more than two candidates) the ballot 
rules don't constrain voters to expressing fewer than three 
preference-levels, and A wins being voted above B on more 
than half the ballots, then it must not be possible to make B 
the winner by altering any of the ballots on which B is voted 
above A.*

Does anyone else think that this is highly desirable?
 
Is it new?
[end quote]

I think it's probably new. I have a reservation about how desirable it
is, because you're guaranteeing that this A (preferred by a majority to
B) can hang on to his win, but only when A would win in the first place.
It's hard for me to judge whether A ought to be able to continue to 
win when I don't know why he won in the first place. It seems to me I'd
rather state why A's original win should be guaranteed. (I think this
direction may lead to SFC or votes-only SFC.)

All things being equal it is desirable, of course.

Kevin Venzke