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. 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. 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. 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. 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. 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. 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. 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. 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.
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. 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. 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. 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
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. 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. 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. 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. 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. 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
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. 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.
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. 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
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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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
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
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. 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.
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. 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. 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. 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. 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