A Method for Combining Asymmetric Three-Value Predictions of Time or Cost,
Abstract
A method is shown for readily finding the sum or product of Weibull distributions corresponding to three-value predictions of time or cost. The predictions must each be in the three-value form: a most likely value falling between high and low values having specified probabilities of occurrence. The first, second, and third moments of each Weibull distributions are found suing dimensionless graphs entered with an 'asymmetry quotient' found arithmetically from the original prediction values. Then the moments of the individual distributions are combined to find the three moments of the overall distribution. If desired, these combined moments can be converted to the three-value form of the original estimates--a low, most likely, and high figure. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1972
- Accession Number
- AD0745404
Entities
People
- William H. Sutherland