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This presentation outlines the key components of Project Evaluation and Review Technique (PERT) and Critical Path Method (CPM). The presentation specifically covers how PERT is used alongside CPM and the impact it has on the process. The following topics are included in the overview:
Project managers often use PERT integrated into CPM to reduce the level of uncertainty that arises when calculating task time frames.
The Program Evaluation and Review Technique (PERT) is a statistical tool used in project management to analyze the tasks involved in completing a project. It was developed by the United States Navy in the 1950s.
At the same time, the Critical Path Method (CPM) was also developed, which is a project management system that distinguishes between critical and non-critical tasks to prevent delays or mistakes in scheduling. The aim of CPM is to avoid interruptions or errors that could lead to problems with time management or scheduling.
The integration of PERT with CPM leads to a more skeptical estimation of the time required for each task of a project. The key difference between CPM alone and CPM integrated with PERT is the formula used for time calculation.
CPM alone uses a three-point estimation:
The optimistic time
The most likely time
The pessimistic time
The estimates are based on experiences from similar past projects and experts’ judgments. The formula used is:
E = (a + 4m + b) / 6
When PERT is integrated with CPM, a similar three-point analysis is done but with slightly different terms:
The shortest time
The mean time
The longest time
The formula used is:
Shortest time + 4 x Most likely time + Longest time
In summary, integrating PERT with CPM reduces reliance on guesses and aims to calculate better time estimation for individual tasks. Though project scheduling always involves some speculation, this approach limits it.