ANOTHER ESTIMATE OF EXPECTED CRITICAL PATH LENGTH IN PERT NETWORKS

The Program Evaluation and Review Technique PERT is a very well- known and widely-applied method for estimating the amount of time required to complete a complex project. The simplest way to estimate the expected time to complete the project is to assume each subtask takes exactly its expected time to complete and then find a critical path. This procedure, except in very simple cases, gives an underestimate of the true expected time required. In 1962 D. R. Fulkerson published a technique for estimating the expected time required which gives values intermediate between the simplest estimate and the true value. The present paper suggests another technique which, while more complex than Fulkersons method, is more accurate in that it gives estimates which fall between Fulkersons estimates and the true expected value.