There is continuing interest by academics and practitioners alike in measuring and coping with project schedule uncertainty. Fuzzy logic has been proposed as an alternate approach to probability theory for quantifying uncertainty related to activity duration. However, the fuzzy logic approach is not widely understood, and generally accepted computational approaches are not available. This paper describes the differences between the probabilistic and fuzzy approaches and the advantages of the latter. The paper also illustrates a straightforward approach for applying fuzzy logic to assess project schedule uncertainty.
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