[EM] IRV in Burlington VT

[Warren Smith]

>> Given this experience, I would suggest that Burlington switch to a
>> method different from plurality and different from IRV.   Some obvious
>> contenders are approval and range voting.
>
> Warren, why is Condorcet not included?

--well, let's see.  First of all, there are problems with rank-order
ballots, some of which Burlington indeed encountered.  Like

* What if I rank A top and B bottom, but nobody in between?
Burlington treated this as "A top, all rest coequal last."  Probably wrongly.

* What if I rank A and B coequal?
Most IRV elections treat this as "your vote is discarded"
but probably better would be "half a vote for each."

Those problems do not arise with range or approval.
That's one reason life is simpler.

San Francisco got a factor 7 increase in ballot spoilage when they switched to
IRV, see
   http://www.rangevoting.org/SPRates.html

Range and approval also of course are simpler than Condorcet to count, ignoring
issues of ballot-casting-errors.

There are other issues with Condorcet too, like there are many
variants, but it'd be a lot to go into.   You can see some here
   http://www.rangevoting.org/RangeYieldsCondSumm.html

> the problem with Approval voting is that it requires too little
> information from the voters.
> and the problem with Range voting is that it requires too much.

--well, actually, not really.   First of all, the "more" info in range
voting appears to
be actually simpler for voters to provide, than the "less" info in a
rank-order or approval vote. See
  http://www.rangevoting.org/ManyChoices.html#hot
so you might as well go for more, since range voting is simpler for
both voters and for counters than Condorcet & IRV, and fewer voter
errors.

However, approval is simpler than range voting for counting and in
terms of voter error-reduction.

In terms of simplicity Approval>Range>Condorcet & IRV.

In terms of winner-quality  Range>Condorcet&IRV&approval>plurality,
in my opinion.

> if you support a particular candidate (let's say the Dem) but you
> approve of two (say both the Dem and the Prog), you have a problem
> with voting strategy with Approval.  maybe, depending on how other
> folks vote, you can help your favorite against the candidate you
> tepidly support, so you punch "Approve" for your fav only.  or, maybe
> your fav is actually not in really in the running and the election
> becomes a contest between your fallback candidate and the guy you
> think is a piece of crap.  then "what to do, what to do?? oh me oh
> my!" (the savvy voter must thing strategically.)  most people will
> just approve the single candidate they support and, if nearly all do
> that, there is no difference between Approval and Plurality.

--well, you are right this can be an issue with approval voting,
although it it's more dubious you are right that most voters will just
vote plurality-style.   I think approval
voting will look like plurality voting in SOME elections, but in most
it will not.  See e.g.
    http://www.rangevoting.org/FrenchStudy.html
where evidently plurality was not being simulated at all.   One of the
virtues of
range voting compared with approval is that it suffers less from that
particular issue.

> again "what to do, what to do?? oh me oh my!"

--well, strategic voting is not easy in Condorcet or IRV either.
In fact, it is probably harder.  But a lot of voters just use the naive strategy
of ranking A top & B bottom where A & B are the two "appear most likely to win"
candidates (e.g. Dem & Repub).   With that voting strategy, Condorcet and IRV
will always elect the same winner as plain plurality, and hence should still
lead to 2-party domination developing. This has historically been the
case with IRV.
For Condorcet it is more dubious.

For the fact IRV rarely switches the winner away from the plain-plur
winner, while the
(sounds similar!) non-instant "top-2-runoff" system switches a lot
more often, see
    http://www.rangevoting.org/TTRvsIRVrevdata.html

> the Ranked-Order Ballot extracts the correct amount of information
> from the voter.

--wouldn't agree with that one.   It discards strength information.
That matters a lot in Hitler vs Carter vs Ford.  Well, you maybe want
to indicate you
like Hitler a LOT less than C & F, but you cannot.  (Or Stalin vs
Hitler vs Carter.)
So then those who like Hitler a little more, win the election, and
those who like him
a lot less, i.e. Jews, lose the election.  And their lives.   Because
strength info
was ignored even though all voters were perfectly willing to honestly
provide it if only they'd been asked.

> even though there is the *possibility* of a cycle (and thus a
> *possible* strategy of some to try to throw a Condorcet election into
> a cycle) the likelyhood is soooo low, because of political alignment
> along the major axis of the political spectrum.

--I'm unsure how likely it is.  Everybody else is unsure too, because enough
data simply has never been collected to be sure.
A cycle just happened in the Romania president election, see
   http://www.rangevoting.org/Romania2009.html

Maybe it happened in a lot of other elections too. Maybe not and Romania
was a fluke.  No way to know for sure.   My bias tends to be the same
as yours, i.e.
I'm guessing top-cycles are 1% or 2%, but it is only a guess.

> some of us are morons, that is true.

--especially the ones who vote against you :)


-- 
Warren D. Smith
http://RangeVoting.org  <-- add your endorsement (by clicking
"endorse" as 1st step)
and
math.temple.edu/~wds/homepage/works.html