Project Time Management

2. Project Time Management

3. I have no idea how long it will take. I do not even know what I am being asked To do. So what do I say? I’ll take my best guess and double it!

4. Estimating Activity Duration • Expert judgment • Analogous estimating • Parametric estimating • Three-point estimates • Reserve analysis

5. Creating a Three-Point Time Estimate Average Most likely Pessimistic Optimistic

6. Factoring in Reserve Time • Hidden Time • Procrastination • Demands • On Schedule

7. PERT AND CPM NETWORKS “I keep six honest serving-men (they taught me all I knew); their names are What and Why and How and Where and Who.” Rudyard Kipling

8. History • Late 1950s • Program Evaluation and Review Technique (PERT) • U.S. Navy, Booz-Allen Hamilton, and Lockeheed Aircraft • Probabilistic activity durations • Critical Path Method (CPM) • Dupont De Nemours Inc. • Deterministic activity durations

9. A B D C Constructing a Project Network • Terminology • Activity: an element of theproject that requires time. • Merge activity: an activity that has two or more preceding activities on which it depends. • Parallel (concurrent) activities: Activities that can occur independently and, if desired, not at the same time.

10. C A B Constructing a Project Network (cont’d) • Terminology • Path: a sequence of connected, dependent activities. • Critical path: the longest time pathway through the activity network that allows for the completion of all project-related activities; the shortest expected time in which the entire project can be completed. (Delays on the critical path will delay completion of the entire project). D

11. Basic Rules to Follow in Developing Project Networks • Networks typically flow from left to right. • An activity cannot begin until all of its activities are complete. • Arrows indicate precedence and flow and can cross over each other. • Identify each activity with a unique number; this number must be greater than its predecessors. • Looping is not allowed. • Conditional statements are not allowed. • Use common start and stop nodes.

12. Network Information TABLE 6.1

13. Koll Business Center—Partial Network FIGURE 6.3

14. Koll Business Center—Complete Network FIGURE 6.4

15. Network Information TABLE 6.2

16. Network Computation Process • Forward Pass—Earliest Times • How soon can the activity start? (early start—ES) • How soon can the activity finish? (early finish—EF) • How soon can the project finish? (expected time—ET) • Backward Pass—Latest Times • How late can the activity start? (late start—LS) • How late can the activity finish? (late finish—LF) • Which activities represent the critical path? • How long can it be delayed? (slack or float—SL)

17. Activity-on-Node Network FIGURE 6.5

18. Forward Pass Computation • Add activity times along each path in the network (ES + Duration = EF). • Carry the early finish (EF) to the next activity where it becomes its early start (ES) unless… • The next succeeding activity is a merge activity, in which case the largest EF of all preceding activities is selected.

19. Activity-on-Node Network Forward Pass FIGURE 6.6

20. Backward Pass Computation • Subtract activity times along each path in the network (LF - Duration = LS). • Carry the late start (LS) to the next activity where it becomes its late finish (LF) unless... • The next succeeding activity is a burst activity, in which case the smallest LF of all preceding activities is selected.

21. Activity-on-Node Network Backward Pass

22. Determining Slack (or Float) • Free Slack (or Float) • The amount of time an activity can be delayed without delaying connected successor activities • Total Slack • The amount of time an activity can be delayed without delaying the entire project • The critical path is the network path(s) that has (have) the least slack in common.

23. Activity-on-Node Network with Slack FIGURE 6.8

24. Sensitivity of a Network • The likelihood the original critical path(s) will change once the project is initiated. • Function of: • The number of critical paths • The amount of slack across near critical activities

25. Extended Network Techniques to Come Close to Reality • Laddering • Activities are broken into segments so the following activity can begin sooner and not delay the work. • Lags • The minimum amount of time a dependent activity must be delayed to begin or end • Lengthy activities are broken down to reduce the delay in the start of successor activities. • Lags can be used to constrain finish-to-start, start-to-start, finish-to-finish, start-to-finish, or combination relationships.

26. Example of Laddering Using Finish-to-Start Relationship FIGURE 6.12

27. Use of Lags (cont’d) Use of Lags to Reduce Detail

28. New Product Development Process

29. Extensions to Precedence Diagramming • Finish-to-start linkage • Start-to-start linkage

30. Finish-to-finish linkage • Start-to-finish linkage

31. THE GANNT CHART

32. A Gantt Chart of a Sample Project

33. A Gantt Chart of Sample Project Showing Critical Path, Path Connections, Slack, EST, LST, EFT, and LFT

34. A Gantt Chart of a Day Care Project Showing Expected Durations, Critical Path, Milestone, and Resource Requirements

35. A Progress Report on a Day Care Project Showing Actual Progress Versus Baseline

36. Gantt Chart – Don’t Manage Your Project Without It • Because the Gantt Chart is such a traditional tool and appears so simple on the surface, it doesn’t always get the respect it deserves as a project management tool. Here are some of the uses of a Gantt Chart. Management reports. The simplicity and visual strength of a Gantt Chart makes it the ideal tool to use when you’re reporting to someone who doesn’t know project management. Testing the Time constraint. When you’re doing preliminary project planning and have numerous parallel tasks, you often don’t know how long the project will take in calendar time. The Gantt Chart will show you. Allocating resources. The Gantt Chart helps you to allocate and track resources and identify conflicts.

37. Gantt Chart – Don’t Manage Your Project Without It What-If analysis. You can explore many options visually and determine which one(s) are best for your project. Resource management. The “Resource Gantt Chart” works both in controlling resources on a single project and in managing resources across projects in a multiple project environment. Tracking progress. The “Tracking Gantt Chart,” which allows you to compare actual project performance to plan, shows you the consequence of tasks not finishing on their assigned times, and gives you a tool to explore options.