lecture 6

Chapter 6:Chapter 6:Project Time ManagementProject Time Management

Information Technology Information Technology Project Management, Sixth Project Management, Sixth EditionEdition

Note: See the text itself for full citations.

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


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


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


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 nameAn activity identifier or numberA 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.


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


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.


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.


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.


Figure 6-2. Sample Activity-on-Arrow (AOA) Network Diagram for A Project

10


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.


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.


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

..


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


Figure 6-4. Sample PDM Network Diagram

15


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.


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.


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.


PERT Formula and Example

19

PERT weighted average = optimistic time + 4X most likely time + pessimistic time

6Example:PERT weighted average = 8 workdays + 4 X 10 workdays + 24 workdays = 12 days

6where optimistic time = 8 daysmost likely time = 10 days, andpessimistic time = 24 days

Therefore, you’d use 12 days on the network diagram instead of 10 when using PERT for the above example


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


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


Gantt Charts (Continue)

22

Sample Gantt Chart


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).


Figure 6-5. Gantt Chart for a Project

24

Note: Darker bars would be red in Project 2007 to represent critical tasks.


Figure 6-6. Gantt Chart for Software Launch Project

25


Figure 6-8. Determining the Critical Path for A Project

26


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


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


Calculating Early and Late Start and Finish Dates

29


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

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 asEarliest finish time = Earliest start time + Expected activity time

Earliest start = Largest of the earliest finish times ofimmediate predecessors

ES = Largest EF of immediate predecessors

EF = ES + t

ACTIVITY tES EFLS LF

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 = 2ES = 0 EF = 0 + 2 = 2

B t = 3ES = 0 EF = 0 + 3 = 3



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


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

How to Find the Critical Path General Foundry’s ES and EF times

A 20 2

C 22 4

H 213 15

E 44 8

B 30 3

D 43 7

G 58 13

F 34 7

Start Finish

Figure 13.4


How to Find the Critical Path Latest times are computed as

Latest start time =Latest finish time – Expected activity timeLS = LF – t

Latest finish time = Smallest of latest start timesfor following activities

LF = Smallest LS of following activities

For activity H

LS = LF – t = 15 – 2 = 13 weeks

How to Find the Critical Path General Foundry’s LS and LF times

A 20 20 2

C 22 42 4

H 213 1513 15

E 44 84 8

B 30 31 4

D 43 74 8

G 58 138 13

F 34 7

10 13

Start Finish

Figure 13.5 LS = LF – t LF =Smallest LS of following activities



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

From Table 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

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

How to Find the Critical Path General Foundry’s critical path

A 20 20 2

C 22 42 4

H 213 1513 15

E 44 84 8

B 30 31 4

D 43 74 8

G 58 138 13

F 34 7

10 13

Start Finish

Figure 13.6


Assignment

41


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


44

Crashing : It is the process by which duration of project is reduced by INCREASING the amount of RESOURCES allocated

Fast Tracking : 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.


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.


Table 6-1. Free and Total Float or Slack for Project X

46


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 reportsA schedule change control systemProject management software, including schedule comparison

charts like the tracking Gantt chartVariance analysis, such as analyzing float or slackPerformance management, such as earned value (Chapter 7)


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.


Working with People Issues

49

Strong leadership helps projects succeed more than good PERT charts.

Project managers should use:EmpowermentIncentivesDisciplineNegotiation


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


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 activitiesSequence activitiesEstimate activity resourcesEstimate activity durationsDevelop scheduleControl schedule

lecture 6

Education

sequence of project

project scope

project deliverables

project team members

specific activities

sequence activities

editiondefining activities

editionsequencing activities