Intelligence
What is Analysis of Competing Hypotheses?
A structured method for testing several explanations against the evidence and favouring the one with the least evidence against it.
Analysis of Competing Hypotheses, developed by Richards Heuer at the CIA, is a structured analytic technique. The analyst lists every reasonable hypothesis, lays out the evidence in a matrix and marks how consistent each item is with each hypothesis.
The key step is focusing on evidence that rules hypotheses out, rather than collecting support for a favourite. ACH reduces confirmation bias and makes the reasoning behind a judgement visible to others.