7.1 Introduction

A simulation of a dynamic system only has value if it represents the simulated system with sufficient accuracy for its intended purposes. Any simulation development effort must take steps to demonstrate that the resulting simulation provides a satisfactory level of accuracy. These steps are an integral part of the simulation effort and should be planned from the start of the project.

The accuracy of a simulation is demonstrated using a process called verification, validation, and accreditation, or VV&A for short. I will provide a brief definition of each of these terms and then discuss the entire process in detail in the remainder of this chapter.

Verification demonstrates that a simulation has been implemented correctly according to its design specifications.

Validation demonstrates that a simulation accurately represents the behavior of the simulated system and related external effects for the simulation's intended purposes.

Accreditation is an authoritative statement that a simulation is acceptable for its intended uses, usually provided by the ultimate users of the simulation results.

VV&A is a process involving three major steps that generally proceed in the order listed above. The verification step is relevant for any software development process and simply indicates that the software performs as its designers intended. In simulation work, verification can occur in the early stages of a product development project. It is not necessary to have data derived from system prototype testing to perform verification. As a result, we can perform verification for a simulation of a system that does not...