Definition of Analysis of competing hypotheses

The Analysis of Competing Hypotheses (ACH) is a methodology for exploring and evaluating several explanations of observed data. It was developed by Richards Heuer in the 1970s for use by the Central Intelligence Agency   and is used by analysts in various fields who deal will making judgements which entail high risk of error in reasoning because of cognitive limitiations or short-term memory and other perceptual biases. It helps an analyst overcome, or at least minimize, some of the cognitive limitations that make prescient intelligence analysis so difficult to achieve.