Bryan Caplan  

Nuclear Iran Bet

McArdle (and the Pope) on air ... Predicting failure...
John Podhoretz:
The United States and its allies have struck a deal with Iran that effectively ensures that it will be a nuclear state with ballistic missiles in 10 years, assuming Iran adheres to the deal's terms, which is a very large assumption.
Such supreme confidence cries out for a bet.  Draft terms: John gives me 10:1 odds that Iran possesses a nuclear weapon by July 31, 2025 according to (a) any major U.S. newspaper (NYT, WSJ, up to three others of John's choice) or (b) any major international agency (Atomic Energy Commission, U.N., up to three others of John's choice).  If this happens, I immediately owe him $100.  Otherwise, he owes me $1000 on August 1, 2025.

I'm happy to make the same bet with any prominent individual on their honor, or with anyone willing to prepay me. (When the bet starts, PayPal me whatever you owe me if you lose.  If you win, I refund your money + whatever I owe you + some interest if you like).

COMMENTS (15 to date)
Peter H writes:

Apart from the 10:1 odds, this is a fairly generous bet, since you've excluded the ballistic missile question entirely. Getting a warhead small, light, and robust enough to be deliverable by ballistic missile is a nontrivial technical challenge.

It's not an unreasonable exclusion since it would be hard to tell if Iran has done it, but it's still one of the points of fact Podhoretz made.

Tom Woods writes:

I sent this out to my nearly 33,000 Twitter followers. So the bets should come rolling in any time now, Bryan.

Greg G writes:

I'd like to know what assumptions everyone is making here about when Iran gets the bomb in the absence of this agreement.

Grant Gould writes:

Is the bet conditional on the deal being enacted and adhered to on the US side? If the next president reneges on the deal, as the Republican candidates have mostly promised to, it seems pretty likely that the Iranian government will have to race for a bomb to prepare for or deter war (and to satisfy angry domestic constituencies).

I'd definitely favor your side of the bet conditional on US adherence (at 10:1 odds? I'd take it in a heartbeat!), but without that condition it's pretty close to a wash.

More precisely, I think odds of US adherence are less than 40%, and odds of an Iranian government sprinting for a bomb if the US does not adhere are greater than 95%.

Ron Nitz writes:

Hooray! Bryan thinks it's somewhat less than a 90% chance that Iran will have nuclear weapons in a decade! (actually, it's that we will publicly know about them, not that they have them.)

Mike W writes:

It seems to me you've got the odds should be giving him odds.

The odds should reflect the outcome on which you are willing to lend your influence. On his position, to which he is publically committing his prestige, if he is wrong and Iran does not have the bomb the outcome for the world would be favorable. On the other hand, on the position you are attempting to influence, if you are wrong the risk to world peace is considerably greater.

The bet you are proposing seems to be a piddling no-cost proposition for should be giving him 1,000:1 odds at least.

Richard writes:

Will you please challenge those afraid of terrorism to a bet? You see them on cable news all the time saying we're all going to die. A large portion of the public considers this the biggest problem in society.

How about this: Of all murders on American soil in the next 1/5/10 years, less than 5% will have some ideological motivation, whether Islamist, white supremacist, or whatever.

If nobody will take that bet, everyone should shut up about terrorism.

Nathan writes:

Mike W, I think you are misunderstanding Bryan's position. I very much doubt he has any strong view about what the outcome of the Iran deal would be. Rather he is keen to puncture falsely inflated confidence in pretty much anything.

Jesse writes:

Mike W:

Adding to Nathan's comment, Bryan is trying to make money here - if he thinks the true probability is 0.85, he's making a statistically good bet.

But I suspect he's laying off his risk by making 1:1 odds bets on another blog somewhere, like a true bookmaker. :-)

Mike W writes:

Nathan writes: I very much doubt he has any strong view about what the outcome of the Iran deal would be. Rather he is keen to puncture falsely inflated confidence in pretty much anything.

Tsk-tsking about others hyperbole doesn't seem to me to be a very worthwhile ambition. But if all he aspires to be is a gadfly I guess we can just ignore him.

Mark V Anderson writes:
Tsk-tsking about others hyperbole doesn't seem to me to be a very worthwhile ambition.

If we could somehow deflate hyperbole in public discourse, that would be a tremendous benefit to public debate. I might even read a blog that was solely devoted to deflating hyperbole, as long as it was ideologically neutral.

Kevin Driscoll writes:

Mike W,

It isn't about tsk-tsking or any other kind of moral disapproval. It also isn't about working toward the end upon which one bets. It's about putting yourself and your intellectual position at close personal risk so that you can grow when you're wrong. Bryan doesn't just propose these bets as a form of criticism - he frequently takes them and pays up when he loses.

The point of it is that predictive systems without feedback don't learn anything. If you just make predictions without close personal consequence then your cognitive biases cloud your judgment and memory. You're very unlikely to act differently the next time. But, when there is a tight feedback loop like a monetary wager, people are much more likely to remember that they were wrong and incorporate that new evidence.

Michael Moran writes:

Question, why the 9 to 1 odds. Do you think Iran will not have a nuke in 10 years, or just hit is uncertain?

Do you support the proposed deal, or you just think the conservatives claims go too far.

Do you have a view how this impacts Iran supporting various nasty people around the world.

Do you think this deal will bring iran into the mainstream of nations, abiding by the rules of international law as its supporters think.

Pete Dushenski writes:


Why you'd want to use PayPal in the year 2015, much less in 2025 when one can only imagine that it'll be the latter day equivalent of snail mail, and to boot why you'd imagine that USD$ 1`000 will be enough to buy so much as a hotdog in a decade is, well, a bit kooky.

You'd be far better served and far better off making this proposal on BitBet and seeding it with 0.33 BTC or whatever $100 is atm. Maybe you'll get 10:1 on your initial wager, but maybe you'll get 100:1 or even 1`000:1. Either way, the market will decide and you'll open the door to a lot more action than just Mr. Kerry, who may not even be on this side of the green grass when the bet's resolved.

Just a thought. Cheers.

Michael Miller writes:

The most significant economic aspect of your bet is the fact that he must give you the $1000 and you are able to invest it for 10 years. He gives up 10 years of investing his money, and gives that to you! That's too much value he's giving you relative to his best possible outcome. Even if he's certain that after 10 years, you will give him his money back plus 10% ($100) -- 100% certain that he will win the bet, and that you will be around to pay it, etc. -- he still wouldn't do it. You have to eliminate the advance payment to make this a fair bet.

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