Chapter 8: PERT, CPM, GERT. Originated from Govern./Research (Navy/Lockheed) Focus on time Optimistic, most likely and pessimistic time . Originated from private Industry Focus on cost Crash Time and Crash cost. PERT x CPM (both 1950s). PERT Formulas p.231-232.
Optimistic, most likely, and pessimistic time
Estimated time of task
Estimate Variance of task
Estimated time of project
Estimated variance of project
Based on idea that a project has a Normal Time to complete a job. Normal time is the cheapest. If it takes longer or shorter, it will
usually be more expensive.
Q: Example of a project where not all tasks need to be completed for the project to be completed ?
A2: You research three different possible solutions to cure cancer (three different groups). Once one group solves the problem, other group (tasks) can be disactivated.
A1: To decide if you give credit or not to somebody you do three types of credit check. If any two comes through with success, credit is conceived.