Detlof von Winterfeldt1
International Institute for Applied Systems Analysis
Risk is defined as a combination of three elements: scenario, probability, and consequences. A scenario is a sequence of events that is a subset of mutually exclusive and exhaustive sequences of events that could happen in a particular risk context. Probabilities reflect the relative likelihood of scenarios. Consequences (for example, fatalities, injuries, economic impacts) are defined at the end of the sequence of events.2
This general definition of risk and has withstood the test of time and applies to natural disaster risks, technological risks, and terrorism risks. ...