PMBOK® Guide - Fourth Edition and the PERT formula
The new Project Management Institutes, A Guide to the Project Management Body of Knowledge, (PMBOK® Guide) - Fourth Edition, Project Management Institute, Inc., 2008 explicitly states the PERT formula in both Time and Cost Management chapters. PERT stands for Program Evaluation and Review Technique. It is used to provide a more accurate estimate by considering the estimation uncertainty and risk. PERT factor in best case (optimistic) and worst case (pessimistic) estimates. The PERT formula is: (O+4M+P)/6 Where O is the optimistic estimate, P is the pessimistic estimate and M is the most likely estimate The formula is easy to remember and will probably come up in the Project Management Professional (PMP)® exam. So learn it and pick up easy points for it in the PMP® certification exam.
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