Generation of input data for simulations

Simulation of large projects and of complex processes on digital computers has become a common practice. Choice of proper input data for such a simulation nearly always constitutes a serious problem because of the difficulty in predicting what the actual data will be when the project or process is put into operation. Examples are costs and prices (in market simulations and business games), enemy and own strategy and strength (in war games), atmospheric and space conditions (in flight simulations), raw material and power supply (in production simulations), climatic conditions and water flows (in hydrological and hydroelectric simulations), etc.