Since our national economy depends, to an extent, on the successful completion of the design, marketing and selling of major industrial projects, one sees more exacting demands placed on the completion of these projects on time. For example we have seen the advent of increased Ministerial requirements on the estimations of development costs and programmes with the subsequent stricter control of the costs and programmes of advanced technological projects. In order to facilitate the implementation of the requirements specified in the Downey Report, and in particular, industry's own monitoring and programming, we have seen the development of network analysis management techniques.

Projects having slipped several months or even years tend to incur escalated costs and consequently one sees a loss in overall profit, lost future orders, etc. It would be more than useful, therefore to estimate a probability function of completing a project by a specified date in order that more realistic planning can be executed.