PERT Method (Program Evaluation and Review Technique) is one of the standard methods of network analysis. PERT Method is a generalization of the Critical Path Method (CPM). PERT is used to manage complex actions having stochastic nature. Here, the duration of each sub-activity is understood as a random variable having a probability distribution. Empirically it was found that in practice the beta distribution describes it the best because it better reflects the variability of operating conditions (e.g. mining operations).
The aim of the PERT models is such an arrangement of activities that would ensure a compliance with the deadline of the project with sufficiently high probability. The basic difference from the CPM is, that the duration of the activity is not precisely known but it is given only with a certain probability. This duration is not constant but a random variable with a certain probability distribution. Due to the nature of issues addressed in the project management, the beta distribution was chosen for the classical practices. This distribution is very close to the normal distribution, it is continuous, single, slightly, asymmetrical, but unlike normal it is bounded on both sides.
How to use of the PERT Method in practice?
This method can be used, as well as other methods of network analysis, to estimate the project duration. It is used as an alternative to CPM. PERT is a method mainly used in project management and in the field of logistics and transportation.