On 5/28/2013 12:51 PM, David L Wetzell wrote:
Richard Fobes wrote:
Plurality voting and limited voting (and the Borda count if the voters
are undisciplined) are about the only methods that _cannot_ handle 3 or
(maybe) 4 popular choices along with any number of unpopular choices.
So you agree that IRV works w. relatively few popular candidates?
The results for IRV get worse as the number of candidates increase.
Condorcet methods give fair results regardless of the number of
candidates. Approval voting gives reasonably fair results regardless of
the number of candidates.
IRV can usually -- but not always -- handle 3 candidates. And IRV can
sometimes handle 4 candidates. But IRV becomes quite unreliable -- and
also vulnerable to strategic voting -- if there are 5 or more candidates.
> So it seems disengaged from reality to let C, the number of
candidates,
> go to infinity... and if a lot of candidates are not going to get
> elected then to disregard voter info/preference over them is of much
> less consequence.
Although the number of popular candidates is now small, that's because
we use plurality voting. When we use better voting methods, the number
of popular candidates will increase; of course not to infinity, but
frequently beyond the 3 or 4 popular choices that IRV can handle with
fairness.
dlw: This is a conjecture. One that I don't think makes economic sense
when one considers all that is entailed with a competitive campaign for
an important single-seat election.
The biggest campaign contributors (a.k.a. special interests) have forced
voters into the Republican and Democratic parties, and then taken
control of the primary elections of both parties by taking advantage of
vote splitting. All sorts of things will change when these constraints
are removed.
My point is that Condorcet and Approval methods can handle whatever
number of parties arise. In contrast, IRV will fail if there turn out
to be more than 3 or 4 effective parties, so IRV is not a reliable choice.
Although it's a non-governmental example, take a look at the current
VoteFair American Idol poll. The number of popular music genres is
about 5, and there are about 7 singers who get more than a few
first-choice votes.
http://www.votefair.org/cgi-bin/votefairrank.cgi/votingid=idols
IRV would correctly identify the most popular music genre (based on
current results), but probably would not correctly identify the most
popular singer.
Apples and Oranges.
There's no serious economic costs to competing in American Idol and so
the number of competitive singers is not naturally hampered by that and
the need for a large support base or expensive advertisements or
connections for important endorsements.
Here you seem to be saying that IRV is OK in governmental elections even
though it can't handle a singing contest.
Why would voters trust a voting method that stops getting fair results
with so few popular candidates?
Because when one considers the potential candidates have for taking on
ideas, there isn't a need for a large number of candidates to make the
de facto center much more like the true center.
Only among theorists does one constrain candidates to fixed positions in
policy-spaces.
Actually I see politics as multi-dimensional, which is why I don't talk
about left and center and right (because that's one-dimensional).
Yes, IRV is easy to explain, but that advantage becomes unimportant as
the number of popular candidates increases, which it will when better
voting methods are adopted.
That may be your story, but when one adds realism with folks able to
express voice thru other means besides voting then it becomes less
important to amp up C much. The non-competitive candidates can still
move the center.
I don't know what your words here mean. As I said, "center" implies
one-dimensional thinking, and I see things as multi-dimensional (which
means there is lots of cross-party voting [although mainstream media
mistakenly calls those voters "undecided"]).
And the opportunity cost of trying to settle on an alternative
alternative to FPTP than IRV will become apparent.
I support the idea of having (initially, small) organizations try out
different kinds of voting and letting that process educate citizens as
to what works and what doesn't.
This means I oppose the belief that IRV is the only method that should
be tried. It has been tried, and the results have not been impressive.
One broader point underlies this discussion. A major reason why the
U.S. has only two political parties is that if a third-party
Presidential candidate gets even a (relatively) few _electoral_ votes,
that would likely block a majority of votes going to either the
Republican or Democratic candidate, and that would throw the election
into the House of Representatives (with each state getting one vote),
and the House is not going to choose the third-party candidate. That
scenario has happened in the past, and the after-effect is the
abandonment of an otherwise strong third party. IRV would not solve
this problem, yet many proponents of IRV seem to think it would, and
accordingly (but mistakenly) they promote IRV as a way to help third
parties grow in popularity.
Richard Fobes
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