Overview of the Operations Research Modeling Approach

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the bulk of this book is devoted to the mathematical methods of operations research (OR). This is quite appropriate because these quantitative techniques form the main part of what is known about OR. However, it does not imply that practical OR studies are primarily mathematical exercises. As a matter of fact, the mathematical analysis often represents only a relatively small part of the total effort required. The purpose of this chapter is to place things into better perspective by describing all the major phases of a typical large OR study. One way of summarizing the usual (overlapping) phases of an OR study is the following:

1. Define the problem of interest and gather relevant data.

2. Formulate a mathematical model to represent the problem.

3. Develop a computer-based procedure for deriving solutions to the problem from the model.

4. Test the model and refine it as needed.

5. Prepare for the ongoing application of the model as prescribed by management.

6. Implement.

Each of these phases will be discussed in turn in the following sections.

The selected references at the end of the chapter include some award-winning OR studies that provide excellent examples of how to execute these phases well. We will intersperse snippets from some of these examples throughout the chapter. If you decide that you would like to learn more about these award-winning applications of operations research, a link to the articles that describe these OR studies in detail is included on the book’s web- site, www.mhhe.com/hillier.

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