Documented point by point refutation of Cobb / Green-party pro-IRV video

by Warren D. Smith, Oct. 2016

The following youtube video was posted by David Cobb, former Green Party nominee for US president and present head of Stein/Baraka US Green party presidential campaign, on 6 October 2016:

How Ranked Choice Voting Prevents 'Spoilers':

Unfortunately a large set of the claims Cobb makes in the video are false, including its title itself is a lie.

Cobb 0:17-0:27: "I and you have the right to cast a vote for the candidate who most represents our principles and values. And if we do not have a voting system that encourages that, then let's acknowledge that the voting system is the problem."

RESPONSE: Great principle! Unfortunately, it is false to pretend IRV obeys that principle. (Score voting, however, does obey it.)

With IRV (instant runoff voting, the system Cobb is advocating in this video, but which he instead very misleadingly calls 'ranked choice voting') voters cannot vote for their favorite candidate without sometimes causing the election result, in that voter's own view, to worsen.

Let me repeat and clarify.

FACT 1: With the IRV system, elections exist, and are indeed fairly common, where if you, like an ignoramus, like Cobb, foolishly honestly vote FOR the GREEN, that act CAUSES the GREEN and your 2nd-favorite candidate BOTH TO LOSE. If, on the other hand, you had dishonestly IRV-voted for your 2nd-choice (and thus "betrayed" that Green) that would have CAUSED that 2nd choice to win, thus getting a superior election result in your view.

FACT 2: With the IRV system, elections exist, and are indeed fairly common, where if you, like an ignoramus, like Cobb, foolishly honestly vote for the GREEN, that act CAUSES the GREEN and the 2nd-favorite candidate BOTH TO LOSE. If, on the other hand, you had dishonestly IRV-voted for your 2nd-choice (and at the same time ranked the Green dishonestly dead last) that would have CAUSED that Green to win. I repeat: sometimes you can make the Green win by ranking him bottom, but ranking him top on your IRV ballot would have caused him to lose.

PROOFS: For a simple worked-thru example IRV election, see

PROOF OF FACT 2: In that election, regard B as the Green candidate. Note that B loses. But if 2 B>C>A voters, who note had ranked B top, instead dishonestly vote C>A>B, pretending that they hate Greens, then that would have made the Green B win.

Those voters evidently did NOT have the "right to cast a vote for the candidate who most represented" them – or at least, if they exercised that right, it sure backfired!

PROOF OF FACT 1: Notice how in this election the Green B is a "spoiler" because he by the act of running, prevented C – the second-favorite and "lesser evil" of the Green voters – from winning. If the Green B had dropped out of the race (or if all voters had refused to rank B above bottom), then C would have won the election. But because of B running and his supporters ranking him top, A, the "greater evil" wins.


for computer determination of probabilities of different IRV fiascos in three different probability models. The "spoiler effect" like in fact 1 happens in 22 to 34 percent of 3-candidate IRV elections in which "IRV matters", and in 9 to 20 percent of 3-candidate IRV elections generally. The "nonmonotonicity effect" as in fact 2 happens in 7 to 17 percent of IRV elections generally and 10 to 43 percent of IRV elections in which "IRV matters." ("IRV matters" in an election means that the IRV and plain plurality voting processes produce different winners. The reason I say "10 to 43" percent and not just one number, is that there are three probability models, explained there, and you get a different occurrence rate in each model.)

Cobb 0:38: "It's called 'ranked choice voting' and its as easy as 1-2-3... It's just that simple."

RESPONSE: Sorry, the system Cobb recommended really is called "instant runoff voting" and it is so complicated that Cobb just lied about it, presumably because he did not understand it (unless it was an intentional lie). That worked simple IRV election I pointed you to before – please actually READ it:

Now: do you seriously believe all those crazy phenomena are simple and easy as 1-2-3, totally obvious?

The reason it is NOT called "ranked choice voting" – except by liars – is that actually there are an infinite number in principle (and well over 100 that have actually been seriously proposed) different possible kinds of voting systems based on rank-order ballots. Instant Runoff is only one of those many different systems, and not even a very good one. The lying propaganda organization "FairVote" came up with the idea of lying to people by pretending IRV was the only "ranked choice" system – by pretending its name was "ranked choice voting" – that lie suited their purposes. Do not join the lie team. Join the truth team.

Cobb 0:47: "empowers you the voter to actually fully express your opinion."

Actually, score voting empowers the voter to score each candidate, thus expressing not only an ORDERING of who is preferred over who, but also BY HOW MUCH (strong and weak preferences). But IRV does not allow the voter to express the latter, no matter how much the voter wants to. Also, score voting allows a voter to intentionally express ignorance about a candidate and leave him unscored – but IRV does not (if you try, then you'll effectively by ranking that candiate dead last, which is the opposite of ranking him "unknown"). So Cobb is just wrong when he uses the word "fully" since obviously IRV is only allowing a partial kind of expression of opinion compared to score voting.

Further, with IRV, even the amount of "expression" you have is often a lie, since RAISING the ranking of the Green candidate in your preference ordering can CAUSE HIM TO LOSE as we saw above (fact 2).

To start to learn about score voting, also called range voting, see =

(and the simplified but less-good form approval voting of score also has its virtues). The fact score is the system used by honeybees should perhaps impress you (as a Green).

Cobb claims IRV yields "actual majority winner"... again, I suggest you read that same simple worked-thru IRV election example

and also this other example specifically devoted to the IRV versus majority issue

for counterexample worked-thru IRV elections where it is made clear that these claims are highly misleading. (E.g. the "actual majority winner" can be the same person as the "actual majority loser" to use Cobb's own words. How can both be the same? Ever? Well, Cobb misled, that is how.) For a real-world IRV election where IRV "thwarted the majority" (same election also contained both nonmonotonicity and an IRV spoiler!) see the mayoral election in Burlington Vermont 2009:

and note Burlington repealed IRV soon after this election.

Cobb 1:44: with IRV we "eliminate the spoiler effect"

Simply a flat out lie. Recall the above counterexample IRV election which involved a spoiler, and the Burlington real-world counterexample election, and fact 1. (Even a single counterexample somewhere in the universe would suffice to show this was false; I have many.)

Cobb 1:47: with IRV we "avoid mudslinging and character assassination, encourages... civil tone."

What a lovely world that would be, huh? Unfortunately this claim is not based on valid evidence. There actually was a preliminary paper trying to obtain evidence for claims of this kind, but as I pointed out to its main author Caroline Tolbert in email which she never answered, their statistics were invalid. (Essentially, their entire study was based on just three IRV elections, simply not enough to draw statistically significant conclusions, but they tried anyway but without using or even mentioning statistical techniques like "Bonferroni correction" which are known to be needed to prevent deluding yourself.)

This enhanced-civility claim might even be true, but if so it will not be easy to prove it, and it never has been proven. It is speculation. Meanwhile, IRV is biased in favor of "extremists" and against "centrists" and that really has been proven, and if you want I can direct you to more references on that, but start with

and this bias is likely not going to help with "civility" – if you act uncivil that maybe makes you more extreme-appearing, which will help you win under IRV.

Australia is by far the greatest user of IRV, having conducted more IRV elections than every other country combined (elects its lower house with IRV and has for nearly 100 years). Perhaps Cobb should have taken note that the Australian Greens, apparently every other Australian 3rd party, and the Australian populace as a whole, all want to get rid of IRV; and that IRV has yielded massive 2-party domination in Australia's IRV-elected house. Only a single third-party member ever won election to their House during 1950-2015 in a normal (not special vacancy-filling) IRV election. His name is Adam Bandt.

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