Probability Methods for Cost Uncertainty Analysis, 2nd Edition

5

Functions of Random Variables and Their

Application to Cost Uncertainty Analysis

This chapter presents methods for studying the behavior of functions of

random variables. Topics include joint probability distributions, linear combi-

nations of random variables, the central limit theorem, and the development

of distribution functions specic to a general class of software cost-schedule

models.

5.1 Introduction

Functions of random variables occur frequently in cost engineering and anal-

ysis problems. For example, the rst unit cost UC of an unmanned spacecraft

might be derived according to (Lurie and Goldberg 1993)

0.94 0.30

UC = 5.48(SC

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