A model for managing the cost of reliability

To assist management in planning reliability efforts, a parametric model has been developed to estimate the distribution of effort which will maximize the return on investment of reliability effort. To develop the model, reasonable mathematical descriptions were developed to describe the development of unreliability in a product and the costs of correcting the unreliability. The resulting equations were found to be readily differentiable, and as a result, minimization criteria were easily developed. The equations and minimization criteria were programmed on a personal computer to examine the effects of varying the parameters to data on cost and reliability achievement strategy, and to allow the calibration of model parameters of the development process and the reliability obtained from several development programs. The completed model is used to explore program cost associated with different assumptions on the growth rates of unreliability and cost of unreliability removal