Black Swan. A term popular in BCM, based upon a book of the same name in which the author defines a Black Swan as an event that has not been predicted by normal scientific or probability methods.
Black swan events can take many shapes, from terrorist attacks to disruptive technologies. These events typically fit fat-tailed probability distributions, i.e. they exhibit greater kurtosis than a normal distribution. Unlike other types of risk events which are relatively certain and predictable, such as car accidents and health events (‘white swans’), ‘black swans’ cannot be predicted by relying on backward-looking probabilistic approaches that assume normal distributions
- Bank of International Settlements, 2020