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Black swans

In short, if you want to use this term, make sure you used it to describe major – force majeure as a matter of fact – events that prove devastating but unpredictable.

Here are media examples:

1. For now, the hubris of spurious precision has given way to humility. It turns out that in financial markets “black swans”, or extreme events, occur much more often than the usual probability models suggest. Worse, finance is becoming more fragile: these days blow-ups are twice as frequent as they were before the first world war, according to Barry Eichengreen of the University of California at Berkeley and Michael Bordo of Rutgers University. Benoit Mandelbrot, the father of fractal theory and a pioneer in the study of market swings, argues that finance is prone to a “wild” randomness not usually seen in nature. In markets, “rare big changes can be more significant than the sum of many small changes,” he says. If financial markets followed the normal bell-shaped distribution curve, in which meltdowns are very rare, the stock market crash of 1987, the interest-rate turmoil of 1992 and the 2008 crash would each be expected only once in the lifetime of the universe.

This is changing the way many financial firms think about risk, says Greg Case, chief executive of Aon, an insurance broker. Before the crisis they were looking at things like pandemics, cyber-security and terrorism as possible causes of black swans. Now they are turning to risks from within the system, and how they can become amplified in combination.