SUMMARY OF EXAMPLES OF PERFORMING SIMULATIONS ON SPREADSHEETS WITH ANALYTIC SOLVER PLATFORM

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SUMMARY

Increasingly, spreadsheet software is being used to perform simulations. As illustrated in Secs. 20.1 and 20.4, the standard Excel package sometimes is sufficient to do this. In addition, some Excel add-ins now are available that greatly extend these capabilities. ASPE is an especially powerful add-in of this kind.

When using ASPE, each input cell that has a random value is referred to as an uncer- tain variable cell. The procedure for defining an uncertain variable cell includes selecting one of 46 types of probability distributions from the Distributions menu to enter into the cell. When historical data are available, ASPE also has a procedure for identifying which continuous distribution fits the data best.

An output cell that is used to forecast a measure of performance is called a results cell. Each trial of a simulation run generates a value in each results cell. When the simulation run is completed, ASPE provides the results in a variety of useful forms, including a frequency distribution, a statistics table, a percentiles table, and a cumulative chart.

When a simulation model has one or two decision variables, ASPE provides a para- meter analysis report that systematically applies simulation to identify at least an approximation of an optimal solution. A trend chart also provides additional insights to aid in decision making.

In addition, ASPE includes a powerful optimization module called Solver. This module efficiently uses a series of simulation runs to search for an optimal solution for a simulation model with any number of decision variables.

The availability of such powerful software now enables managers to add simulation to their personal tool kit of OR techniques for analyzing some key managerial problems. A variety of examples in this chapter illustrate some of the many possibilities for important applications of simulation.

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