Kevin Venzke wrote:
Hi Kristofer,
--- En date de : Sam 19.2.11, Kristofer Munsterhjelm <km-el...@broadpark.no> a
écrit :
Some other observations: it seems that adding a Smith
constraint (Smith, or Smith//) limits the vulnerability to
compromising, and that having the base method satisfy LNHarm
greatly limits vulnerability to burial, since the base
method is then immune to burial.
Well actually it's LNHelp that gives you immunity to burial. (DSC, QR, and
MMPO are vulnerable in varying ways.) And sadly it seems to me that the
desirability of having other voters doubt that you will express a certain
lower preference, mitigates the advantage of LNHarm.
If you look at LNHelp instead you will probably start out with
Condorcet//Approval, which actually is one of my favorite methods due to
anti-burial properties. Maybe DAC is of interest too.
If that's the case, then LNH isn't enough. See Armytage's strategy
paper, http://www.econ.ucsb.edu/~armytage/svn2010.pdf . In it, Bucklin
is shown to be vulnerable to burial (e.g. page 28). This is quite
strange because Bucklin isn't Condorcet-efficient and so could (and
does) meet LNHelp outright.
It also seems possible to bury using Bucklin. Say that your sincere
preference is A > B > C > D, and that B wins in the second round, but if
you could somehow keep B from winning, then A would win in the third.
Then dishonestly burying B, say by voting A > C > D > B, would help.
A method that passes LNHarm doesn't have this problem, AFAIK, because
later preferences cannot harm your earlier preferences. Your chance of
having A win is the same whether you vote A > B > C > D or A > D > C > B.
----
Election-Methods mailing list - see http://electorama.com/em for list info
