robert bristow-johnson wrote:
my understanding is that the later-no-harm result happens only if the
case of a Condorcet cycle (the prevalence of which i am dubious about).
where there is a Condorcet winner and that person is elected, is there
still possible later harm?
As far as I remember, Condorcet and LNHarm has the property that LNHarm
isn't, by itself, violated as long as there is a CW, but the transition
from CW to no CW (or vice versa) makes it inevitable that there will be
a LNHarm-violating discontinuity *somewhere*.
In other words, as long as you stay within the CW domain, there is no
LNHarm failure, but there is no way to engineer a completion rule to
maintain this for every CW<->no CW transition.
I'm not entirely sure about that, though - can anyone confirm?
Not that this bothers me - LNHarm seems to me to be a criterion of
"don't take the full picture into account". Consider a negotiation
situation: if everybody keeps their cards close to their chests (i.e.
vote bullet style), there can be no compromise; but if they're willing
to reach further, one might find an option that, while not the favorite
of any, is good enough for all. An LNHarm-respecting method has to act
as if people are voting cautiously before it can consider any additional
information, and thus it misses such opportunities for compromise.
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