[Election-Methods] Fwd: [LWVTopics] IRV Voting

[Abd ul-Rahman Lomax]

At 03:47 PM 5/15/2008, Juho wrote:
>Here's one style of vulnerability of IRV that has not been discussed
>that much.
>
>In elections that have many candidates that represent small interest
>groups, and when there are so many such candidates that practically
>all voters have at least one such candidate that closely reflects
>their views, then those candidates that appeal to many voters may not
>be the first preferences of practically any voters.

Right. I think we need to remember how IRV was invented. First of 
all, "IRV" is a neologism, a term coined in the 1990s by a friend of 
Rob Richie and then promoted as the name for single-winner STV in the 
U.S. For practical reasons, all the applications actually being 
implemented are not full preference ballots. San Francisco, for 
example, allows only three ranks, and with over *twenty* candidates 
on the ballot for some city council seats, it's understandable that, 
if people vote sincerely, a lot of people end up not influencing the 
result. In fact, in 23 IRV elections in the U.S., held since 2004, 
that went to runoff rounds (were not won by a majority in first 
preference), only two (I don't think it was three) found a majority 
of ballots. In San Francisco, by comparison, in one election there 
was enough ballot data given to allow Bucklin analysis. Bucklin found 
a majority in more elections. IRV loses votes, because they may be 
buried. The very characteristics that FairVote touts as features are 
the root cause of some of the problems.

Later-no-harm is incompatible with the discovery of a majority, 
though I don't recall the details. And "core support," of course, 
guarantees the weird scenario that Joho describes. IRV is sold as 
allowing sincere voting of true first preference.

Okay, suppose voters take that literally, and write in the name of 
the person they most trust for the office, sincerely, without 
restrictions. Condorcet methods and Approval, etc., can handle this 
without a problem. But IRV goes bonkers. If we have a three-candidate 
election, with the three running neck-and-neck, but everyone prefers 
one of the three as a second choice, it is quite obvious who the best 
winner is. But with IRV, it's a tossup. One time out of three, the 
Condorcet winner is disqualified in the first round, and the votes of 
that winner are then distributed. What I've been seeing in real 
elections is that these distributed votes are likely to be samples 
from the same population. I.e., they will tend to be awarded to the 
other candidates in the same proportion as with the population of all 
those who voted for those other candidates. (This is a truly 
remarkable finding, and I'd love it if someone would confirm it -- or 
refute it. Data is available from San Francisco, Burlington, and 
Cary, NC, I've looked at them. There may be some others.)

Anyway, we have a situation where IRV cannot predict who will win (it 
depends on the second preference votes entirely, except that second 
preference votes for the Condorcet winner are not seen or counted, 
because that candidate was eliminated in the first round. So if this 
is A, B, C, with the A:B pair, if counted with Bucklin or a Condorcet 
method, would be a landslide for A, but then IRV may (one time out of 
three) choose B or C. The difference is a few votes, radically 
changing the result. This is why Yee diagrams for IRV are so chaotic 
in this region. Bucklin shows the true situation: A is everyone's 
second choice.

FairVote argues for the importance of "core support," a Criterion 
that they made up because IRV supposedly satisfies it. (It doesn't, 
actually.... but it would take very special circumstances for it to 
fail.) The reality behind core support is that such support is 
ordinarily necessary to (1) get on the ballot and (2) run a 
successful campaign. If a candidate could actually win without 
plurality core support, well, I'd be amazed. However, because of the 
nature of IRV elections, "core support" does not mean that a 
plurality (or even one voter) actually prefers the winner, first 
preference, for the voters may not have voted their first preference, 
since to do so is foolish, tosses away that vote. Systems which allow 
full ranking, including a write-in, don't have this problem. Asset 
Voting, in particular, would allow *totally* sincere voting, and it's 
an extraordinarily simple method. Just count the votes..... Quota 
required to win. Asset Voting was invented for multi-winner, but it 
could easily be used for single-winner, and it totally avoids the 
supposedly universal election paradoxes. By punting. Asset voting is 
not a method that necessarily resolves in one ballot.

Anyway, yes, suppose that the voters are divided up into *many* small 
factions. If people vote for their favorite, it can be quite quirky 
and unpredictable what happens in the first round. So, easily, a 
candidate who would be the second choice of nearly everyone could be 
eliminated. To my mind, it is almost criminal to not consider all the 
votes cast, which Condorcet methods, Approval, and Bucklin do.

(Bucklin is counted in rounds, and, if a jurisdiction didn't want to 
spend the money, and a majority is found in the first round, later 
votes might not be counted. But I'd say, if the voters put the effort 
into voting, we should put the effort into counting. Whatever method is used.)

IRV is sold as replacing runoff elections, that was the very purpose 
of the name invention. But IRV does not, apparently, behave at all 
like top-two runoff. In one-third of the elections I examined, before 
IRV, top-two runoff, in San Francisco and Cary, reversed the 
first-round preference. The runner-up in the first round ended up 
winning the runoff. But once IRV was implemented, there were no 
reversals. Period. In every election I looked at, the leader in the 
primary won the runoff, but, even more striking, *the runner-up in 
the primary remained the runner-up in the runoff.*

We are starting to see why Plurality voting was used. It works as 
well as IRV, almost always. Now, why did they have those runoffs in 
the first place? Well, one time out of three, the election reversed. 
That means one of two things: the former runner-up was really the 
Condorcet winner, which plurality could not discover *because of lack 
of sufficient "core support."* -- or, alternatively, differential 
turnout explains the difference. Now that does not explain what 
happened in Cary, NC, for the runoff was held with the general 
election, the primary is the special election, i.e, not on the 
general election ballot, held a month earlier. It might in San Francisco.

But if this reversal was a bad thing, it would have been much easier 
and much cheaper to get rid of it entirely. Don't require a majority! 
If we want to require a majority to support a candidate for the 
candidate to win -- and that was the law in San Francisco -- then IRV 
doesn't do it. It may be that *nothing* but a runoff can do it. Basic 
democratic process doesn't use elimination in runoffs; it requires a 
majority and if there is no majority, there may be voluntary 
withdrawals or additional nominations, essentially a new election is 
held. But as a compromise, whatever method is used for the primary, 
if the results don't show a majority of support, then a runoff should 
be held -- if one wants the winner to have such support.

In selling IRV, all this was, of course, not mentioned. It's not 
clear that anyone even understood or expected it. The ballot 
proposition in San Francisco that started up RCV there was 
deceptively sold. Di they know it was deceptive? I think it is likely 
that some knew. San Francisco had election code that required that 
the winner receive a majority of ballots cast in the election, or 
there would be a runoff. "Instant runoff voting," I'm sure, looked 
very attractive. Have the runoff without holding a separate poll! The 
voter information pamphlet explicitly said that the winner would 
still be required to gain a majority of votes. But the actual 
proposition struck the majority requirement from the code. If they 
had implemented preferential voting without striking the requirement, 
then the claim would have been true.

Why did they strike it? Someone had to understand that IRV, with 
plurality winners, was violating the old provision. Otherwise they 
would just have left it in place.

Now, some IRV supporters have seen this argument, and their response 
has been, "But they wanted to get rid of the expensive runoffs." 
Sure. Who wouldn't? But they *also* wanted majority winners, and the 
"majority of last round votes" that IRV reports is *not* a majority 
winner by any traditional definition. They had to get rid of that 
legal provision, which meant that they were getting rid of the 
majority requirement, not continuing to "require" it, as the voter 
information pamplet claimed. If they wanted to avoid the expense, 
they could have obtained the *same* election results as IRV, almost 
certainly, by just dropping the requirement. Or, better, they could 
have implemented Approval or, probably even better in terms of 
allowing first preferences to be expressed, Bucklin. No big expense. 
More likely to find a majority. And then, in the situations where a 
majority is not found, *you hold a runoff*.

The characteristics of top-two runoff, or of other methods used with 
majority-failure such as Bucklin or Range or Approval, have not been 
much studied. (With Range, approval cutoff is needed; ballot 
instructions could state that any vote of 50% or higher would be 
considered approval for this purpose. Approval or Bucklin, of course, 
explicitly approve.) What I've realized is that the runoff is a test 
of preference strength. If the voters have a strong preference for 
one of the choices over the other, they will preferentially turn out 
to vote, compared to those with a weak preference. This would, then, 
improve the average voter satisfaction with the result. It's a 
Range-like result, and could explain the popularity of top-two 
runoff. If this is true, then IRV is definitely a step backwards, and 
when it is actually being used (i.e., when runoff rounds are 
counted), it is producing worse results about a third of the time.

FairVote has always tried to frame the debate as IRV vs. Plurality, 
but actual major victories have been in places where the heavy cost 
of implementation could arguably be saved by avoiding runoffs. So the 
real comparison, there, would be between IRV and top-two. IRV is 
being used in some places, and is still being called IRV, with only a 
two-rank ballot. It's presumed that voters know who the frontrunners 
are, and so they will presumably vote for one of them in second rank.

I am finding such twisted logic in the pro-IRV propaganda, it amazes 
me. The opponents of IRV in San Francisco were apparently completely 
flummoxed. Nobody noticed the bait-and-switch. You want majority 
winners? Great idea! But you don't like the cost? Hey, we can sell 
you this nice little baby! A bit expensive, but you'll save every 
election year, lots of money, so it will eventually pay for itself. 
Find Majorities Without Runoff Elections!

The fine print: Majority not required. The "majority found" is found 
by pretending that ballots not containing a vote for the two 
frontrunners aren't important. One could get that result much more 
easily. Just count a plurality poll with the IRV rules, in rounds. 
Eliminate, in each around, candidates with the least number of votes. 
Last round, two candidates, the one with a majority of remaining 
ballots wins. Presto! A majority!

You should have seen the pro-IRV forces complaining about efforts to 
clean up the IRV article on Wikipedia, so that it was less of a 
propaganda piece. Edit wars over what might seem like trivial 
differences. About the use of the word majority. The existing 
language used majority over and over again to mean "majority after 
exhausted ballots are set aside." I'd try to specific it, to make it 
more accurate. "Pendantic! Confusing! Too much detail!"

And then, most recently, yesterday, actually, I notice that the 
Robert's Rules' (RRONR) "recommendation" of "IRV" wasn't. Even less 
than I'd been willing to acknowledge. Robert's Rules describes -- not 
recommends, they clearly dislike it -- preferential voting. Not IRV. 
But they do describe, *as an example of preferential voting*, 
sequential elimination. Then RRONR also describe center squeeze as a 
problem with sequential elimination. The IRV proponents want the 
article to give the Robert's Rules "description" -- they abandoned 
efforts to keep "recommendation," it was really unsupportable -- but 
not, of course, the importance of center squeeze, or any example of 
what Robert's Rules might mean by "preferential voting," in general, 
for the text that may be interpreted as a recommendation in narrow 
circumstances is actually of preferential ballot without specifying 
how it is analyzed, so the obvious question for a reader would be, 
what else is there? Try to mention Bucklin, why, that's "promoting" 
Bucklin. Edit warring has begun over this, at least to some degree.

What did I find? Well, Robert's Rules, in describing sequential 
elimination was not crystal clear what "finding a majority" meant. 
One with a background in parliamentary procedure would, I think, get 
it right. It means a majority of ballots cast, and there is, 
elsewhere in Robert's Rules, some specification of this. But at the 
very end of the section on preferential voting, there is a mention 
that voters should be educated in the use of the method, something 
like, "otherwise they may think that voting an additional preference 
could hurt the chances of their favorite, and this could cause the 
election to have to be repeated."

In other words, they are assuming that "majority" means true 
majority. What they are describing is a method which requires a 
majority or there is a runoff. Period. But then --search the internet 
for Robert's Rules of Order and Instant Runoff Voting -- they are 
using this "recommendation" to use IRV in a way that is quite 
contrary from Robert's Rules. The Robert's Rules form of preferential 
voting avoids runoffs *sometimes*. When there are many candidates, it 
turns out, almost never. Unless you drop the majority requirement, 
and we are circling back to the beginning. Bait and switch says it.

Majority-required voting systems perform much better than many 
election methods people suspect. They are actually hybrid, closer to 
deliberative process. There is no way to guarantee a majority unless 
you constrain and coerce the voters, which they actually do in 
Australia. (You *must* vote, it is against the law not to, and you 
*must* rank all the candidates, or else your ballot is spoiled and 
will not be counted.)

And if voting is as Robert's Rules actually suggests, there isn't 
even a guarantee that an election will complete in two ballots, for 
Robert's Rules, explicitly, dislikes any sort of involuntary 
elimination. New election is what they say. Until the electorate gets 
it together to vote a majority. When Robert's Rules says that 
"preferential voting is fairer than election by a Plurality," that is 
because they have described a method that still requires a majority. 
It simply finds one more efficiently, perhaps. Sometimes a runoff 
will be avoided. But with IRV, as distinct from other forms of 
preferential voting, not very often at all.

And it is not clear how often we would see majority failure if the 
method were, say, Bucklin. San Francisco had such high numbers of 
candidates because they had top-two runoff, and voters could safely 
vote for their favorite in the first round. (Strategy would say 
otherwise, but most voters simply vote honestly when they think they 
can). So a better election method, and top-two is better than simple 
Plurality, is likely to encourage more candidates. These were 
nonpartisan elections, so the party system was largely moot. And with 
lots of candidates, no voting system, itself, can guarantee a 
majority. But some can find it better than others. Counting all the 
votes is, in my opinion, always a good idea!