Aleatoric uncertainty

Definition: Variability in outcomes due to unknowable or inherently random factors. The stochastic component of outcome uncertainty that cannot be reduced through additional sources of information. For example, when flipping a coin, uncertainty about whether it will land on heads or tails.

Related terms: <a href='/glossary/epistemic-uncertainty/'>Epistemic uncertainty</a>, Knightian uncertainty

Reference: Der Kiureghian and Ditlevsen (2009)

Drafted and Reviewed by: Bradley Baker, Nihan Albayrak-Aydemir, Brett Gall, Magdalena Grose-Hodge, Bethan Iley, Charlotte R. Pennington

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