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Chapter 6:Chapter 6:
Project Time ManagementProject Time Management
Information TechnologyInformation Technology
Project M...
Information Technology Project
Management, Sixth Edition
Importance of Project Schedules
2
Managers often cite delivering...
Information Technology Project
Management, Sixth Edition
Project Time Management Processes
3
Define activities: identifyi...
Information Technology Project
Management, Sixth Edition
Defining Activities
4
An activity or task is an element of work ...
Information Technology Project
Management, Sixth Edition
Activity Lists and Attributes
5
An activity list is a tabulation...
Information Technology Project
Management, Sixth Edition
Milestones
6
A milestone is a significant event that normally ha...
Information Technology Project
Management, Sixth Edition
Sequencing Activities
7
Involves reviewing activities and determ...
Information Technology Project
Management, Sixth Edition
Three types of Dependencies
8
Mandatory dependencies: inherent i...
Information Technology Project
Management, Sixth Edition
Network Diagrams
9
Network diagrams are the preferred technique ...
Information Technology Project
Management, Sixth Edition
Figure 6-2. Sample Activity-on-Arrow (AOA)
Network Diagram for A ...
Information Technology Project
Management, Sixth Edition
Arrow Diagramming Method (ADM or
AOA)
11
Also called activity-on...
Information Technology Project
Management, Sixth Edition
Process for Creating AOA Diagrams
12
1. Find all of the activitie...
Information Technology Project
Management, Sixth Edition
Figure 6-2. Sample Tabular Diagram of AOA
for A Project
13
Activi...
Information Technology Project
Management, Sixth Edition
Precedence Diagramming Method
(PDM)
14
Activities are represente...
Information Technology Project
Management, Sixth Edition
Figure 6-4. Sample PDM Network Diagram
15
Information Technology Project
Management, Sixth Edition
Activity Duration Estimating
16
One of the important considerati...
Information Technology Project
Management, Sixth Edition
Three-Point Estimates
17
Instead of providing activity estimates...
Information Technology Project
Management, Sixth Edition
Program Evaluation and Review
Technique (PERT)
18
PERT is a netw...
Information Technology Project
Management, Sixth Edition
PERT Formula and Example
19
PERT weighted average =
optimistic t...
Information Technology Project
Management, Sixth Edition
Developing the Schedule
20
Uses results of the other time manage...
Information Technology Project
Management, Sixth Edition
Gantt Charts
21
Gantt charts provide a standard format for displ...
Information Technology Project
Management, Sixth Edition
Gantt Charts (Continue)
22
Sample Gantt Chart
Information Technology Project
Management, Sixth Edition
Gantt Charts (Continue)
23
Gantt Chart allows to view
 What the ...
Information Technology Project
Management, Sixth Edition
Figure 6-5. Gantt Chart for a Project
24
Note: Darker bars would ...
Information Technology Project
Management, Sixth Edition
Figure 6-6. Gantt Chart for Software Launch
Project
25
Information Technology Project
Management, Sixth Edition
Figure 6-8. Determining the Critical Path for A
Project
26
Information Technology Project
Management, Sixth Edition
Critical Path Method (CPM)
27
 The critical path is the longest ...
Information Technology Project
Management, Sixth Edition
Calculating Early and Late Start
and Finish Dates
28
 Slack or f...
Information Technology Project
Management, Sixth Edition
Calculating Early and Late Start
and Finish Dates
29
Information Technology Project
Management, Sixth Edition
How to Find the Critical Path
30
To find the critical path, need ...
Information Technology Project
Management, Sixth Edition
How to Find the Critical Path
31
In the nodes, the activity time ...
How to Find the Critical Path
 At the start of the project we set the time to zero
 Thus ES = 0 for both A and B
Start
A...
Information Technology Project
Management, Sixth Edition
How to Find the Critical Path
33
Task Dependency Duration
A -- 2
...
Information Technology Project
Management, Sixth Edition
Steps for Calculating the Critical Path
34
First develop a good ...
How to Find the Critical Path
 General Foundry’s ES and EF times
A 2
0 2
C 2
2 4
H 2
13 15
E 4
4 8
B 3
0 3
D 4
3 7
G 5
8 ...
How to Find the Critical Path
 Latest times are computed as
Latest start time =
Latest finish time
– Expected activity ti...
How to Find the Critical Path
 General Foundry’s LS and LF times
A 2
0 2
0 2
C 2
2 4
2 4
H 2
13 15
13 15
E 4
4 8
4 8
B 3
...
How to Find the Critical Path
 Once ES, LS, EF, and LF have been determined, it is a simple matter to find the
amount of ...
How to Find the Critical Path
 General Foundry’s schedule and slack times
ACTIVITY
EARLIEST
START,
ES
EARLIEST
FINISH,
EF...
How to Find the Critical Path
 General Foundry’s critical path
A 2
0 2
0 2
C 2
2 4
2 4
H 2
13 15
13 15
E 4
4 8
4 8
B 3
0 ...
Information Technology Project
Management, Sixth Edition
Assignment
41
Information Technology Project
Management, Sixth Edition
Techniques to Shorten a Project
Schedule
42
Explain Project Cost ...
Information Technology Project
Management, Sixth Edition
43
Information Technology Project
Management, Sixth Edition
44
Crashing : It is the process by which duration of project is ...
Information Technology Project
Management, Sixth Edition
Using Critical Path Analysis to Make Schedule
Trade-offs
45
Free...
Information Technology Project
Management, Sixth Edition
Table 6-1. Free and Total Float or Slack
for Project X
46
Information Technology Project
Management, Sixth Edition
Controlling the Schedule
47
Goals are to know the status of the ...
Information Technology Project
Management, Sixth Edition
Reality Checks on Scheduling
48
First review the draft schedule ...
Information Technology Project
Management, Sixth Edition
Working with People Issues
49
Strong leadership helps projects s...
Information Technology Project
Management, Sixth Edition
Schedule Control Suggestions
50
Perform reality checks on schedu...
Information Technology Project
Management, Sixth Edition
Chapter Summary
51
Project time management is often cited as the...
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Lecture 6

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Lecture 6

  1. 1. Chapter 6:Chapter 6: Project Time ManagementProject Time Management Information TechnologyInformation Technology Project Management, SixthProject Management, Sixth EditionEdition Note: See the text itself for full citations.
  2. 2. Information Technology Project Management, Sixth Edition Importance of Project Schedules 2 Managers often cite delivering projects on time as one of their biggest challenges. Time has the least amount of flexibility; it passes no matter what happens on a project. Schedule issues are the main reason for conflicts on projects, especially during the second half of projects
  3. 3. Information Technology Project Management, Sixth Edition Project Time Management Processes 3 Define activities: identifying the specific activities that the project team members and stakeholders must perform to produce the project deliverables. Sequence activities: identifying and documenting the relationships between project activities. Estimate activity durations: estimating the number of work periods that are needed to complete individual activities. Develop the schedule: analyzing activity sequences, activity resource estimates, and activity duration estimates to create the project schedule. Control the schedule: controlling and managing changes to the project schedule
  4. 4. Information Technology Project Management, Sixth Edition Defining Activities 4 An activity or task is an element of work normally found on the work breakdown structure (WBS) that has an expected duration, a cost, and resource requirements. Activity definition involves developing a more detailed WBS and supporting explanations to understand all the work to be done so you can develop realistic cost and duration estimates
  5. 5. Information Technology Project Management, Sixth Edition Activity Lists and Attributes 5 An activity list is a tabulation of activities to be included on a project schedule that includes following attributes: The activity name An activity identifier or number A brief description of the activity The goal of this process is to ensure that the project team has the complete understanding of all the work they must do as part of the project scope.
  6. 6. Information Technology Project Management, Sixth Edition Milestones 6 A milestone is a significant event that normally has no duration. It often takes several activities and a lot of work to complete a milestone. They’re useful tools for setting schedule goals and monitoring progress. Examples include obtaining customer sign-off on key documents or completion of specific products
  7. 7. Information Technology Project Management, Sixth Edition Sequencing Activities 7 Involves reviewing activities and determining dependencies. A dependency or relationship shows the sequence of project activities. For example, does a certain activity have to be finished before another one can start, can several activities be done in parallel, etc. You must determine dependencies in order to use critical path analysis.
  8. 8. Information Technology Project Management, Sixth Edition Three types of Dependencies 8 Mandatory dependencies: inherent in the nature of the work being performed on a project, sometimes referred to as hard logic . e.g you can’t test until after the code is written Discretionary dependencies: defined by the project team; sometimes referred to as soft logic and should be used with care since they may limit later scheduling options. e.g good practice is to not start detailed design until the users sign off on all of the analysis work. External dependencies: involve relationships between project and non-project activities.  installation of new operating system and other sw depends on delivery of new hw from  an external supplier.
  9. 9. Information Technology Project Management, Sixth Edition Network Diagrams 9 Network diagrams are the preferred technique for showing activity sequencing. A network diagram is a schematic display of the logical relationships among, or sequencing of, project activities. Two main formats are the ADM or AOA and PDM.
  10. 10. Information Technology Project Management, Sixth Edition Figure 6-2. Sample Activity-on-Arrow (AOA) Network Diagram for A Project 10
  11. 11. Information Technology Project Management, Sixth Edition Arrow Diagramming Method (ADM or AOA) 11 Also called activity-on-arrow (AOA) network diagrams. Activities are represented by arrows. Nodes or circles are the starting and ending points of activities. Can only show finish-to-start dependencies.
  12. 12. Information Technology Project Management, Sixth Edition Process for Creating AOA Diagrams 12 1. Find all of the activities that start at node 1. Draw their finish nodes and draw arrows between node 1 and those finish nodes. Put the activity letter or name and duration estimate on the associated arrow. 2. Continue drawing the network diagram, working from left to right. Look for bursts and merges. Bursts occur when a single node is followed by two or more activities. A merge occurs when two or more nodes precede a single node. 3. Continue drawing the project network diagram until all activities are included on the diagram that have dependencies. 4. all arrowheads should face toward the right, and no arrows should cross on an AOA network diagram.
  13. 13. Information Technology Project Management, Sixth Edition Figure 6-2. Sample Tabular Diagram of AOA for A Project 13 Activity Start Node End Node Duration A 1 2 1 B 1 3 2 C 1 4 3 D 2 5 4 ..
  14. 14. Information Technology Project Management, Sixth Edition Precedence Diagramming Method (PDM) 14 Activities are represented by boxes. Arrows show relationships between activities. More popular than ADM method and used by project management software. Better at showing different types of dependencies
  15. 15. Information Technology Project Management, Sixth Edition Figure 6-4. Sample PDM Network Diagram 15
  16. 16. Information Technology Project Management, Sixth Edition Activity Duration Estimating 16 One of the important considerations in making duration estimates is the availability of resources. People, equipment, skill level, no. of people Duration includes the actual amount of time worked on an activity or elapsed time. Effort is the number of workdays or work hours required to complete a task. Effort does not normally equal duration.
  17. 17. Information Technology Project Management, Sixth Edition Three-Point Estimates 17 Instead of providing activity estimates as a discrete number, such as four weeks, it’s often helpful to create a three-point estimate An estimate that includes an optimistic, most likely, and pessimistic estimate, such as three weeks for the optimistic, four weeks for the most likely, and five weeks for the pessimistic estimate PERT is based on three point estimation of duration.
  18. 18. Information Technology Project Management, Sixth Edition Program Evaluation and Review Technique (PERT) 18 PERT is a network analysis technique used to estimate project duration when there is a high degree of uncertainty about the individual activity duration estimates PERT uses probabilistic time estimates Duration estimates based on using optimistic, most likely, and pessimistic estimates of activity durations.
  19. 19. Information Technology Project Management, Sixth Edition PERT Formula and Example 19 PERT weighted average = optimistic time + 4X most likely time + pessimistic time 6 Example: PERT weighted average = 8 workdays + 4 X 10 workdays + 24 workdays = 12 days 6 where optimistic time = 8 days most likely time = 10 days, and pessimistic time = 24 days Therefore, you’d use 12 days on the network diagram instead of 10 when using PERT for the above example
  20. 20. Information Technology Project Management, Sixth Edition Developing the Schedule 20 Uses results of the other time management processes to determine the start and end date of the project Ultimate goal is to create a realistic project schedule that provides a basis for monitoring project progress for the time dimension of the project Important tools and techniques include Gantt charts, critical path analysis
  21. 21. Information Technology Project Management, Sixth Edition Gantt Charts 21 Gantt charts provide a standard format for displaying project schedule information by listing project activities and their corresponding start and finish dates in a calendar format On the left of the chart is a list of the activities and along the top is a suitable time scale Each activity is represented by a bar the position and length of the bar reflects the start date, duration and end date of the activity
  22. 22. Information Technology Project Management, Sixth Edition Gantt Charts (Continue) 22 Sample Gantt Chart
  23. 23. Information Technology Project Management, Sixth Edition Gantt Charts (Continue) 23 Gantt Chart allows to view  What the various activities are  When each activity begins and ends  How long each activity is scheduled to last  Where activities overlap with other activities, and by how much  The start and end date of the whole project To summarize, a Gantt chart shows you what has to be done (the activities) and when (the schedule).
  24. 24. Information Technology Project Management, Sixth Edition Figure 6-5. Gantt Chart for a Project 24 Note: Darker bars would be red in Project 2007 to represent critical tasks.
  25. 25. Information Technology Project Management, Sixth Edition Figure 6-6. Gantt Chart for Software Launch Project 25
  26. 26. Information Technology Project Management, Sixth Edition Figure 6-8. Determining the Critical Path for A Project 26
  27. 27. Information Technology Project Management, Sixth Edition Critical Path Method (CPM) 27  The critical path is the longest path through the network diagram and has the least amount of slack or float.  Slack or float is the amount of time an activity may be delayed without delaying a succeeding activity or the project finish date.  CPM is a network diagramming technique used to predict total project duration.  A critical path for a project is the series of activities that determines the earliest time by which the project can be completed.  There can be more than one critical path if the lengths of two or more paths are the same  The critical path can change as the project progresses
  28. 28. Information Technology Project Management, Sixth Edition Calculating Early and Late Start and Finish Dates 28  Slack or float is the amount of time an activity may be delayed without delaying a succeeding activity or the project finish date. Task Dependency Early Start Duration Early Finish Late Start Late Finish A --- 01-02 5 05-02 05-02 10-02 B --- 01-02 10 10-02 01-02 10-02 C A,B 10-02 7 17-02 10-02 17-02
  29. 29. Information Technology Project Management, Sixth Edition Calculating Early and Late Start and Finish Dates 29
  30. 30. Information Technology Project Management, Sixth Edition How to Find the Critical Path 30 To find the critical path, need to determine the following quantities for each activity in the network 1.1. Earliest start timeEarliest start time (ESES): the earliest time an activity can begin without violation of immediate predecessor requirements 2.2. Earliest finish timeEarliest finish time (EFEF): the earliest time at which an activity can end 3.3. Latest start timeLatest start time (LSLS): the latest time an activity can begin without delaying the entire project 4.4. Latest finish timeLatest finish time (LFLF): the latest time an activity can end without delaying the entire project
  31. 31. Information Technology Project Management, Sixth Edition How to Find the Critical Path 31 In the nodes, the activity time and the early and late start and finish times are represented in the following manner Earliest times are computed as Earliest finish time = Earliest start time + Expected activity time Earliest start = Largest of the earliest finish times of immediate predecessors ES = Largest EF of immediate predecessors EF = ES + t ACTIVITY t ES EF LS LF
  32. 32. How to Find the Critical Path  At the start of the project we set the time to zero  Thus ES = 0 for both A and B Start A t = 2 ES = 0 EF = 0 + 2 = 2 B t = 3 ES = 0 EF = 0 + 3 = 3
  33. 33. Information Technology Project Management, Sixth Edition How to Find the Critical Path 33 Task Dependency Duration A -- 2 B -- 3 C A 2 D B 4 E C 4 F C 3 G D,E 5 H F,G 2
  34. 34. Information Technology Project Management, Sixth Edition Steps for Calculating the Critical Path 34 First develop a good network diagram Add the duration estimates for all activities on each path through the network diagram The longest path is the critical path If one or more of the activities on the critical path takes longer than planned, the whole project schedule will slip unless the project manager takes corrective action
  35. 35. How to Find the Critical Path  General Foundry’s ES and EF times A 2 0 2 C 2 2 4 H 2 13 15 E 4 4 8 B 3 0 3 D 4 3 7 G 5 8 13 F 3 4 7 Start Finish Figure 13.4 ACTIVITY t ES EF LS LF
  36. 36. How to Find the Critical Path  Latest times are computed as Latest start time = Latest finish time – Expected activity time LS = LF – t Latest finish time = Smallest of latest start times for following activities LF = Smallest LS of following activities  For activity H LS = LF – t = 15 – 2 = 13 weeks
  37. 37. How to Find the Critical Path  General Foundry’s LS and LF times A 2 0 2 0 2 C 2 2 4 2 4 H 2 13 15 13 15 E 4 4 8 4 8 B 3 0 3 1 4 D 4 3 7 4 8 G 5 8 13 8 13 F 3 4 7 10 13 Start Finish Figure 13.5 LS = LF – t LF =Smallest LS of following activities ACTIVITY t ES EF LS LF
  38. 38. How to Find the Critical Path  Once ES, LS, EF, and LF have been determined, it is a simple matter to find the amount of slack timeslack time that each activity has Slack = LS – ES, or Slack = LF – EF  FromTable 13.3 we see activities A, C, E, G, and H have no slack time  These are called critical activitiescritical activities and they are said to be on the critical pathcritical path  The total project completion time is 15 weeks  Industrial managers call this a boundary timetable
  39. 39. How to Find the Critical Path  General Foundry’s schedule and slack times ACTIVITY EARLIEST START, ES EARLIEST FINISH, EF LATEST START, LS LATEST FINISH, LF SLACK, LS – ES ON CRITICAL PATH? A 0 2 0 2 0 Yes B 0 3 1 4 1 No C 2 4 2 4 0 Yes D 3 7 4 8 1 No E 4 8 4 8 0 Yes F 4 7 10 13 6 No G 8 13 8 13 0 Yes H 13 15 13 15 0 Yes Table 13.3
  40. 40. How to Find the Critical Path  General Foundry’s critical path A 2 0 2 0 2 C 2 2 4 2 4 H 2 13 15 13 15 E 4 4 8 4 8 B 3 0 3 1 4 D 4 3 7 4 8 G 5 8 13 8 13 F 3 4 7 10 13 Start Finish Figure 13.6
  41. 41. Information Technology Project Management, Sixth Edition Assignment 41
  42. 42. Information Technology Project Management, Sixth Edition Techniques to Shorten a Project Schedule 42 Explain Project Cost Management Processes by giving detail for the following areas: 1. Resource Planning 2. Estimating costs 3. Determining the budget 4. Controlling costs
  43. 43. Information Technology Project Management, Sixth Edition 43
  44. 44. Information Technology Project Management, Sixth Edition 44 Crashing : It is the process by which duration of project is reduced by INCREASING the amount of RESOURCES allocated FastTracking : In fast tracking, activities that were planned to be performed in sequential order are rescheduled to be performed in parallel or partially in parallel Disadvantage is that starting some tasks too soon often increases project risk and results in rework.
  45. 45. Information Technology Project Management, Sixth Edition Using Critical Path Analysis to Make Schedule Trade-offs 45 Free slack or free float is the amount of time an activity can be delayed without delaying the early start of any immediately following activities. Total slack or total float is the amount of time an activity may be delayed from its early start without delaying the planned project finish date.
  46. 46. Information Technology Project Management, Sixth Edition Table 6-1. Free and Total Float or Slack for Project X 46
  47. 47. Information Technology Project Management, Sixth Edition Controlling the Schedule 47 Goals are to know the status of the schedule, identify factors that cause schedule changes, determine that the schedule has changed, and manage changes when they occur. Tools and techniques include: Progress reports A schedule change control system Project management software, including schedule comparison charts like the tracking Gantt chart Variance analysis, such as analyzing float or slack Performance management, such as earned value (Chapter 7)
  48. 48. Information Technology Project Management, Sixth Edition Reality Checks on Scheduling 48 First review the draft schedule or estimated completion date in the project charter. Prepare a more detailed schedule with the project team and get stakeholder’s approval. To establish the schedule it is critical to get involvement and commitment from all project team members, upper management, the customer, and other key stakeholders. Conduct of progress meetings with stakeholders. Alert top management well in advance if there are schedule problems.
  49. 49. Information Technology Project Management, Sixth Edition Working with People Issues 49 Strong leadership helps projects succeed more than good PERT charts. Project managers should use: Empowerment Incentives Discipline Negotiation
  50. 50. Information Technology Project Management, Sixth Edition Schedule Control Suggestions 50 Perform reality checks on schedules Don’t plan for everyone to work at 100% capacity all the time. Hold progress meetings with stakeholders and be clear and honest in communicating schedule issues
  51. 51. Information Technology Project Management, Sixth Edition Chapter Summary 51 Project time management is often cited as the main source of conflict on projects, and most IT projects exceed time estimates Main processes include: Define activities Sequence activities Estimate activity resources Estimate activity durations Develop schedule Control schedule

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