ABSTRACT

This chapter illustrates how key concepts developed thus far combine to produce the probability distribution of a system’s total cost. Chapter 7 will extend this discussion to the joint and conditional distributions of a system’s total cost and schedule. Chapter 6 begins with an introduction to the work breakdown structure, a primary method for organizing a system’s total cost.

The work breakdown structure (WBS) is a framework for identifying all elements of cost that relate to the tasks and activities of developing, producing, deploying, sustaining, and disposing a system. Work breakdown structures are unique to the system under consideration. They are developed according to the specific requirements and functions the system has to perform. WBS are defined for classes of systems. These classes include electronic systems, aircraft systems, surface vehicles, ship systems, spacecraft systems, and information technology systems (Blanchard andFabrycky 1990, United States Department of Defense 2011).