Understanding the Solver Reports

This page will help you understand how to use the information in the reports which you can produce using the Microsoft Excel Solver. You can view a sample Solver model called EXAMPLE1.XLS, and the Answer, Sensitivity and Limits reports which the Solver produces for it. (This model is a simplified version of the Product Mix sheet in the example workbook SOLVSAMP.XLS included with Microsoft Excel.)

All of the reports are Microsoft Excel worksheets, with grid lines and row and column headings turned off. You can turn the grid lines and headings back on, if you wish, through the View tab in the Tools Options... dialog. Because the reports are worksheets, you can copy and edit the report information, perform calculations on the numbers in the reports, or create graphs directly from the report data. This makes the Microsoft Excel Solver's reports considerably more useful than those produced by standalone optimization software packages.

All three types of reports can be useful, but we recommend that you focus on the Sensitivity report. When properly interpreted, this report will tell you a great deal about your model and its optimal solution, that you could not easily determine by simply inspecting the final solution values on the worksheet. Using the Sensitivity report, you can determine what would happen if you changed your model in various ways and re-ran the Solver, without your having to actually carry out these steps.

Selecting the Reports

When the Solver finds the solution to an optimization problem, or when the solution process is terminated prematurely due to some error condition (or your own intervention), the Solver Results dialog is displayed:

If the solution process was terminated prematurely, the Reports List Box in the dialog above will be grayed, and you will not be able to select any reports; you will need to re-solve the problem and obtain an optimal solution in order to produce the reports.

When the Reports List Box is available, you can select one, two, or all three reports. To select any one report, just click on its title with the mouse, or press Alt-R and then down-arrow from the keyboard. You can select more than one report by simply clicking each one in turn -- the SHIFT and CTRL keys are not needed in this context.

Once the reports are selected, you can choose one of the options "Keep Solver Solution" or "Restore Original Values," and optionally save the decision variable values in a named scenario by clicking on the Save Scenario... button. When you click on OK, the reports will be generated. Clicking on Cancel instead will cancel generation of the reports.

Interpreting the Reports

An Example Model (12K)

The Answer Report (14K)

The Sensitivity Report (12K)

The Limits Report (8K)

Copyright © 1996 Frontline Systems Inc.
Last modified: December 01, 1996