The probability yardstick
Seven terms, seven bands. Pick the term whose band matches the evidence, then state your confidence separately. Do not invent your own words.
The scale
The gaps between the bands are deliberate. They stop an analyst claiming precision the evidence has not earned. Realistic possibility sits below an even chance, not above it. It is the term people use wrongly most often.
The second judgement
Probability
How likely the thing is. This is what the scale above measures, and it is the term you end the sentence with.
Confidence
How much weight the judgement can carry, given the sources under it. Stated as high, moderate or low. A high probability call built on one uncorroborated source is still a low confidence call, and it has to say so.
Write both. Then write the one thing that would change your mind.
Bands as published by the UK Professional Head of Intelligence Assessment, in ‘Explaining uncertainty in UK intelligence assessment’ (GOV.UK). The discipline originates with Sherman Kent of the CIA, whose 1951 estimate on Yugoslavia called a Soviet attack a ‘serious possibility’: he meant 65 to 35, and his colleagues took it to mean anything from 20 to 80 percent.
ALCON Intelligence · alconintel.com
