Interesting email from Todd Proebsting, reprinted with his permission.

Dear Prof. Caplan,

Your recent attempt at a wager on Iran’s nuclear progress, and the subsequent exchange with the author about why you wanted 10:1 odds reminded me that the CIA tried to quantify what certain claims meant:

100% Certainty
The General Area of Possibility
93% give or take about 6% Almost certain
75% give or take about 12% Probable
50% give or take about 10% Chances about even
30% give or take about 10% Probably not
7% give or take about 5% Almost certainly not
0% Impossibility

It’s from a 50-year old CIA proposal.

It’s interesting to me that “Almost certain” was only 93%.  I think the CIA would have argued that you should have been asking for even longer odds given the original claim.


Todd Proebsting