Ted Stern wrote (29 Nov 2011):
47: A
05: AB (sincere is A>B)
41: B
07: BC
Approvals: B53, A52, C7
I find this example contrived.
* If mass polling is available, many people will be aware of the
52/48 split between A and B ahead of time.
* Corruption is a separate issue. With proper election funding
control, support for C would be restricted.
Ted,
I reject your criticisms of my example. Of course it's "contrived". So
what? How could it not be?
In my example "many people" as you say are "aware of the 52/48 split
between A and B ahead of time". 95% of them vote as if they are aware
of it.
Approval-Bucklin (AKA ER-Bucklin) has the advantage in your contrived
example of allowing the A > B voters to add B at a lower rank, which
would not count unless neither A nor B achieves a majority.
In many cases, it would not be necessary to rate candidates at the
second (or lower) choice option, but having that option increases the
available nuance of the vote.
Yes. My favourite similar methods are IBIFA and MTA.
However IRV does impose a false choice -- that you must rank your
preferences separately, no equal ranks allowed.
In the case of methods that would fail FBC if they did allow equal-top
ranking, I don't consider this to be a big deal. In the case of IRV,
allowing it would make Push-over strategising easier and the method
more complex to count/implement.
> In my opinion IRV is one of the reasonable algorithms to use with
> ranked ballots, and the best for those who prefer things like
> Later-no-Harm and Invulnerability to Burial to either the Condorcet
> or FBC criteria.
But are these the criteria we really want to achieve in a
single-winner election?
Invulnerability to Burial is a very attractive property to me, but
perhaps not.
To say that LNH is the most important criterion is, at its most basic
level, an emotional argument.
I don't say that, but some people definitely like LNHarm. I prefer its
LHHelp compliance, and regard its LNHarm compliance as only excusable
because of it.
I think what we really want to look for is a method that does a good
job of finding the candidate
closest to the center of the electorate, while resisting strategic
manipulation.
I am mostly in sympathy with that aim. Probably the best methods meet
one of Condorcet and the FBC.
Chris Benham
----
Election-Methods mailing list - see http://electorama.com/em for list info
