A Monte Carlo simulation is used to model the probability of different outcomes in a process that cannot easily be predicted due to the intervention of random variables. It is a technique used to understand the impact of risk and uncertainty. A Monte Carlo simulation is used to tackle a range of problems in many fields including investing, business, physics, and engineering. When faced with significant uncertainty in making a forecast or estimate, some methods replace the uncertain variable with a single average number. The Monte Carlo Simulation instead uses multiple values and then averages the results. (原文出處 )