Two of these were then evaluated using conventional techniques of environmental economic analysis based on productivity losses and contingent valuation methods. This is a lower bound estimate as it excludes values for offshore spills. The analyses illustrate that, relative to direct costs, these potential efficiency losses are substantial. Lesson 3 - Exercise Precaution in the Face of Complexity and Uncertainty Complexity may be thought of as a system's tendency to adapt, to regulate itself, and to produce 'surprises'. Where such systems exist, policymaking must come to grips with decisionmaking under uncertainty.
Uncertainty differs from risk.
By extension, an economic risk assessment is only valid in a deterministic system in which probabilities can be attached to all outcomes. Such risk assessments are not valid for complex system. The simulation of a 'most likely worst case scenario' showed the following concurrent impacts over a 10 year time period. The above conditions changed markedly, however, if the radiation dose was greater than that in the 'most likely' scenario. Simulations showed that irreversible economic collapse would occur if the radiation dose were two times that in the most likely scenario.