[Election-Methods] Dopp: 1. "Does not solve the "spoiler " problem except in special cases."

[Abd ul-Rahman Lomax]

At 11:50 PM 6/11/2008, Greg wrote:
>The FairVote document that debunks Dopp's claims is available at:
>   http://www.fairvote.org/dopp

Or, more accurately, "attempts to debunk." Ms. 
Dopp is a voting security expert, not an election 
methods expert, and some of her statements can be 
flawed, especially if one focuses on technical 
details. I'm going to break this response into a 
series of posts on each separate topic, because 
otherwise it gets *way* too large.

This first section is a good example.

>De-Bunking Kathy Dopp's 15 Flaws of Instant Runoff Voting
>1. Dopp: "Does not solve the "spoiler" problem except in special cases
."
>
>Dopp has her “special cases” reversed. In fact, 
>IRV solves the spoiler problem in virtually all likely U.S. partisan elections.

Which does not contradict Dopp's statement. The 
problem is that "special cases" implies "only 
rare cases," but, technically, IRV *may* reduce 
the spoiler effect in ... a special case, i.e., 
when a minor candidate is not in range of 
winning, but due to vote splitting, causes the 
overall preferred major candidate to lose to one 
less preferred. It does not deal well with the 
center-squeeze effect, where there are three 
candidates in range of winning, and this is, I 
believe, what Ms. Dopp refers to.

Notice the "special case" in the anonymous 
response: it isn't "IRV" solves the spoiler 
problem. There are three hedges: "virtually all," 
"likely," and "partisan." The most operative of 
these restrictions is "partisan." Whoever wrote 
this -- I suspect Rob Richie, and he is certainly 
aware of this interchanges, since he commented on 
it on Wikipedia, in Talk for the article on 
Instant=-runoff voting -- is quite sophisticated. 
IRV, in the absence of the kind of vote transfers 
that take place in partisan elections (where the 
large majority of vote transfers from one 
candidate may favor a single other candidate), 
does little to solve the remaining "spoiler 
effect," center squeeze. It is debatable whether 
or not center squeeze should be called a spoiler 
effect. I've done so in the past, but the 
phenomenon is different, and I'd be happy with 
confining the term "spoiler" to refer to minor 
candidates, not candidates who can actually win 
an election or come close. In which case, indeed, 
Ms.Dopp's statement, as made, would be faulty.

But she is, in fact, talking about center 
squeeze, which is a real problem, one of the two 
that are so notable that Robert's Rules mentions them.

Further, the response wants us to think of all 
U.S. elections when, in fact, IRV is generally 
being proposed as a replacement for real runoff 
elections. Which do not show the spoiler effect 
in anywhere near the same strength as seen with 
Plurality. And where that spoiler effect *is* in 
effect in runoff voting, IRV may well fail to 
resolve the problem; indeed, usually it will.

What has been missed in most discussion of the 
issue is that IRV, as proposed in the U.S., is a 
plurality method. Don't confuse this with 
Majority Criterion compliance. Plurality methods 
will elect a candidate even though a majority of 
voters haven't voted for that candidate, that's a 
simple description of it. Jurisdictions have 
runoff voting because they value finding a 
majority vote for the winner, and top-two runoff 
actually accomplishes this. The truth is that it 
is impossible to guarantee a majority vote in a 
single ballot; it is even impossible with a 
limited series of ballots, except that with 
top-two runoff, because of the ballot design and 
voter habits, a majority will almost always be 
found. (Most top-two implementations allow 
write-in votes, so a maintained preference of 
voters in the first election for an "eliminated 
candidate" can allow that candidate to win. I've 
never seen it, but, usually, when the Condorcet 
winner is eliminated, the preference strength, 
apparently, is not enough to motivate voters to 
turn out and vote write-in. In other words, 
Top-Two runoff, in real practice, works quite 
well, much better than simplistic voting systems theory might predict.

>  Whenever a third party or independent 
> candidate is unlikely to be one of the top 
> vote-getters (true in over 99% of U.S. 
> elections), IRV eliminates the spoiler problem completely.

Actually, no. If you look at Australia, in the 
places where ranking all candidates is optional, 
there is a lot of plumping. So there is still a 
spoiler effect. FairVote has always implied that 
the Australians use a uniform method, but, in 
fact, some places use STV with an absolute 
majority requirement, and they guarantee that 
requirement by voiding all ballots that don't 
fully rank the candidates, and other places use 
Optional Preferential Voting -- which is what is 
proposed for the U.S. -- and plumping -- we call 
it bullet voting -- is common and, apparently, 
increasing, according to Antony Green of ABC. 
Naturally, the majority requirement for OPV is 
relaxed to "a majority of ballots containing 
votes for remaining candidates." That's a 
plurality method. Regular STV, PV, is a majority 
method, but it coerces the votes. Take your pick. 
(Or require a majority, as jurisdictions which 
are using runoff voting do, and then use 
preferential voting, of whatever kind, or 
Approval Voting, to more efficiently find majorities and avoid *some* runoffs.


>  If a third party grows to the point that its 
> candidates out-poll major party candidates, 
> another issue that is related to the spoiler 
> problem can occasionally arise. This is where 
> supporters of a third party candidate may worry 
> that by supporting their favorite candidate, 
> they risk causing their less-preferred 
> compromise choice to be eliminated from the 
> final runoff, leading to the election of their 
> least-preferred choice. In other words, the 
> issue of whether to vote for your favorite 
> choice, or to rank your compromise choice first 
> can resurface in this unique circumstance. But 
> this is extremely rare and no different than a 
> candidate in a party’s political primary 
> arguing “Vote for me because I am more electable in the general election.

This argument presents center-squeeze as if it is 
a strategic voting problem, when, in fact, 
center-squeeze is the problem, and strategic 
voting is how some knowledgeable voters might attempt to fix it.

The problem is not rare if there are three major 
candidates. In that situation, there is no 
candidate that we would ordinarily think of as a 
"third party candidate," which always refers to a 
minor candidate. Three major candidates can occur 
much more commonly in nonpartisan elections than 
in partisan ones, in a two-party system. And, 
remember, IRV is mostly being proposed at this 
time for nonpartisan elections! That is what it 
is being used for in San Francisco.

(Continued with the next point, Dopp: 2. 
“Requires centralized vote counting procedures at the state-level
")