Creating the Crystal Ball Model

  In this case, the model has already been created for you. To review it:

  1. Start Crystal Ball and open the Portfolio Allocation.xls workbook from the Examples Guide.

    The worksheet for this problem is shown in Figure 23, Portfolio Allocation Worksheet, following.

    Figure 23. Portfolio Allocation Worksheet

    Portfolio Allocation worksheet.

    In this example, problem data values are specified in rows 5 through 9. Model inputs (the values of the decision variables), the model output (the forecast objective), and the constraint (the total amount invested) are in the bottom half of the worksheet.

    This model already has the assumptions and forecast cells defined in Crystal Ball. The decision variables are defined as part of this tutorial.

  2. Make sure the assumptions are defined as follows:

    Assumption

    Cell

    Distribution

    Parameters

    Money market fund

    C5

    uniform

    minimum: 2%

    maximum: 4%

    Income fund

    C6

    normal

    mean: 5%

    standard deviation: 5%

    Growth and income fund

    C7

    normal

    mean: 7%

    standard deviation: 12%

    Aggressive growth fund

    C8

    normal

    mean: 11%

    standard deviation: 18%

    If you need help viewing or defining assumptions or forecasts, see the Oracle Crystal Ball User's Guide.

  3. Select Run, and then Run Preferences, Run Preferences button., and set the following run preferences:

    • Maximum number of trials to run set to 1000

    • Sampling method set to Latin Hypercube

    • Sample Size For Latin Hypercube set to 500

    • Random Number Generation set to Use Same Sequence Of Random Numbers with an Initial Seed Value of 999