[EM] Does IRV elect "majority winners?"
Abd ul-Rahman Lomax
abd at lomaxdesign.com
Wed Jan 7 11:16:57 PST 2009
At 07:44 PM 1/5/2009, Kathy Dopp wrote:
>IRV/STV cannot claim majority winners, not only because ballots are
>exhausted and not considered in the final counting round, but also
>because not all voters' choices are even fairly and equally considered
>during the counting process - thus resulting in winners who are
>disliked by a majority of voters and overlooking candidates who are
>preferred by a majority of voters casting votes in the contest.
IRV cannot claim to *consistently* find a majority winner, though
this is indeed claimed by advocates.
I disagree with Ms. Dopp, however, on one thing. The elimination of a
Condorcet winner doesn't, itself, guarantee that IRV won't find a
majority winner in spite of that, it depends.
"Majority" doesn't mean "best," necessarily. It simply means that, in
an election, more than half of the voters chose to vote for a candidate.
What does this mean, "vote for a candidate?" IRV obscures it, and, we
see, in Burlington, that many voters chose to vote for candidates
whom they clearly didn't support, because they apparently had an idea
that it was a "good thing" to rank all the candidates. By ranking all
the candidates that were on the ballot, they were, effectively,
voting for a candidate whom they most certainly didn't approve and
would likely prefer to see a runoff than to elect this candidate.
Usually this is moot, because when they bottom-ranked a candidate
whom they detested, they were only voting for this candidate over a
write-in; so only with a massive write-in campaign could this become
an issue, where the top two were a write-in and the candidate these
voters ranked last.
Basically, IRV, when it fails to find the Condorcet winner, where,
indeed, the ballots show an eliminated candidate as being preferred
to the IRV winner, nevertheless can claim that the winner won by an
absolute majority, if that happens. Usually, though, because of
truncation, which will be fairly common for those who voted for the
Condorcet winner (that is, they truncate with that candidate, who is,
by the conditions of this problem, probably in second rank for many),
there will be majority failure as well.
Thus if there is a real runoff *and if write-in votes are allowed in
the runoff*, the voters *could* fix it. Robert's Rules of Order
describes STV as a means of finding majorities and *not* as a runoff
replacement, a true majority of ballots cast is still required. What
they may not have realized is that IRV is particularly bad at this,
in nonpartisan elections -- i.e., practically all elections in bodies
advised by RRO. American Preferential Voting -- Bucklin -- does much
better, because, if necessary to find a majority, it reveals all the
votes and counts all of them. And it is *far* simpler to canvass.
Just count all the votes in each rank. Add them as necessary to find
a majority.
If they are all added and no majority is found, then there are two
paths to take: terminate with a Plurality, which is honestly shown in
the results, or hold a runoff. Because Bucklin was sold as finding
majorities from a single ballot, the latter was never considered.
This should sound familiar. Those who ignore history are condemned to
repeat it.
>Abd ul is right that Top two runoff is a lot better system, and TTR is
>most likely less costly, definitely is easier to count and more
>auditable, is fairer, and both elections are monotonic too.
TTR has some obvious problems, which are easy to fix. Quite simply,
use a better method in the primary, one which will efficiently find
true majorities, thus reducing the need for runoffs.
Then, allow write-ins in the runoff, and use a better method for that
as well. Bucklin, two-rank, would be *great* for this, because it
would allow write-in voters to still participate among the two
candidates on the ballot. Usually, in the majority of actual office
elections like this, there would be a majority in the primary; it's
hard to say what percentage, though, it depends on context and the
number of candidates.
If they are partisan elections, a majority in the primary gets more likely.
Then, I'd predict, a majority would be found in the runoffs, almost
always, yet it would no longer be a majority coerced by the method.
Write-ins would have a chance, and the situation where something went
wrong in the primary can be fixed *if the voters care enough about it.*
Basically, a proper goal would be to reduce runoffs, but not to
eliminate them. It is also possible, with some kinds of plurality
results, to predict with very high confidence that a runoff would
produce the same result. However, a majority requirement is very
clear and simple, and, in my view is quite adequate.
Where one could set the bar lower than that isn't clear to me. I'd
suggest that with better methods in the primary and runoff, with a
majority requirement in the primary (not in the runoff), problems
would be minimized, and analysis of results over many elections would
reveal where it might be safe to set a lower bar than majority in the
primary, thus avoiding some more runoffs.
First priority: preserve Top Two Runoff. It's the most advanced
voting system we have in common use in the U.S., particularly in
nonpartisan elections, which is where it is mostly used.
There are some grounds for preferring IRV in partisan elections,
where it does, sometimes, improve results, but in the nonpartisan
elections where FairVote has promoted IRV most heavily, IRV is
clearly inferior. They only manage to sell it in that context by
making false promises, such as:
Find majorities. In fact, where doesn't find a majority in the first
round, it doesn't usually find one at all. This isn't obvious to most
people until they study the method and how it actually works.
Reduce negative campaigning. There is no evidence for this, actually.
Think about it: most seriously negative campaigning takes place in
partisan elections, where there are normally only two truly viable
candidates. The supposed motive behind the reduction is an attempt to
gain second-preference votes, but second-preference votes, among
supporters of the top two, are moot. IRV never counts them! They only
become relevant in a three-way race. From the San Francisco
experience -- with nonpartisan elections -- there isn't any evidence
of a reduction in negative campaigning. Some minor candidates, who
don't usually waste a lot of effort excoriating each other anyway,
since it's pretty much all moot, have cooperated, encouraging their
supporters to vote together for them, holding common campaign events.
While this may be a beneficial effect, to some degree, it's moot in
terms of finding the winner, almost always. And it doesn't reduce
negative campaigning.
Lower costs. As Ms. Dopp notes, this may be directly false. It's a
complex issue: voting equipment and software can be expensive, and
standard equipment and software, that jurisdictions may already have,
often can't handle IRV. Hand auditing can become a nightmare with
IRV. There isn't any actual analysis from experience showing reduced
costs, only some projections, rather optimistic ones, that it might.
IRV is being promoted as a cost reducer in L.A., when there are much
simpler methods, including better timing of elections so that the
primary is held with the general election, that would reduce costs
far more. Further, what should really be on the table as an
alternative, American Preferential Voting, as it was called, or the
Grand Junction method, or Bucklin, provides most of the benefits of
IRV without the complicated counting and center squeeze problem of
IRV. By 1918 or so, 55 cities in the U.S. were using it. I'd still
like to know what happened to it: there were many articles published
and available on-line about the *implementations* of APV, but it's
very difficult to find anything about its disappearance.
And there are other arguments presented which are similarly misleading.
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