MIS 578 Chapter 8: Scheduling Projects

Question 1

Project time management processes

Answer 1

PMI has identified the following six time management processes: activity definition, activity
sequencing, activity resource estimating, activity duration estimating, schedule development,
and schedule control.

Question 2

Historical development of project scheduling

Answer 2

PERT and CPM were developed in the 1950s. The AOA and AON methods were used through
the years, but AON is the primary method today. The basic logic remains, but many
advancements have been incorporated into software scheduling systems.

Question 3

How project schedules are limited and created

Answer 3

Project schedules are limited by the logical order of activities, the duration of each activity,
availability of key resources, and imposed dates. Schedules are often developed by considering
each of these four limits in order – that is, first consider logical order, then activity duration, etc

Question 4

Leads and lags

Answer 4

While basic logic says when the predecessor is complete the successor can start, if the successor
can start before the predecessor ends, there is an overlap or a “lead” and if the successor must
be delayed before it can start, there is a gap or “lag.”

Question 5

Learning Curves

Answer 5

Take into account when estimating that the more times a person performs an activity, the faster
they tend to get.

Question 6

Project Schedule Duration Estimation: Two-pass method

Answer 6

Two-pass method
You make two logical passes through the network.

First or forward pass
This is to calculate the early start (ES) and early finish (EF) for each activity.

Second or backward pass
This is to calculate the late start (LS) and late finish (LF) for each activity.

Question 7

Critical Path

Answer 7

Activities on the critical path have zero slack. More than one path can be critical, and if the
project is behind schedule, critical path activities can have negative slack.

Question 8

Project Schedule Duration Estimation: Enumeration Method

Answer 8

This method, by which you list or enumerate all of the paths through the network, provides necessary information for crashing the schedule (a topic in the following chapter). The longest path is the critical path.

Question 9

Uncertainty in project schedules

Answer 9

If it is difficult to estimate activity durations with confidence, the following may be used to deal
with the uncertainty.

Program Evaluation and Review Technique (PERT)
The estimated time for each activity is calculated by the formula optimistic plus 4 times the
most likely plus pessimistic divided by 6.

Monte Carlo Simulation
This flexible technique allows multiple duration estimates for any of the project activities.

Question 10

Before a project schedule can be created, a __________________ must first be made.

Answer 10

WBS

Question 11

List four methods that can be used to create a project schedule.

Answer 11

• PERT
• CPM
• AOA (ADM)
• AON (PDM

Question 12

List and discuss four of the potential limitations for project schedules.

Answer 12

• Logical order
• Length of each activity
• Resource availability
• Dates imposed on project by key stakeholders

Question 13

A(n) _______________________ is a significant event in the lifespan of a project.

Answer 13

milestone

Question 14

A lead is a change in the logical relationship which results in the ____________________ of the successor activity

Answer 14

acceleration

Question 15

f a painted wall must dry for four hours before work can continue, the result is a delay in the successor
activity. The wait for the paint to dry is an example of a(n) ___________.

Answer 15

lag

Question 16

A professor cannot grade his students’ exams until the students have completed taking the test. This is an
example of a __________________ relationship.

• a. start-to-start
• b. start-to-finish
• c. finish-to-finish

Answer 16

finish-to-finish

Question 17

When determining an activity’s duration, project managers typically include weekends, evening, and
holidays in the duration time. True or false?

Answer 17

False

Question 18

When calculating a project’s duration, it is best to consider the time it will take to complete each activity
individually. True or false?

Answer 18

True

Question 19

One potential problem that can occur with activity duration estimating is having omissions. List three
potential remedies for this problem.

Answer 19

• 1. Refining the WBS
• 2. Making checklists
• 3. Having someone play the Devil’s Advocate

Question 20

According to the learning curve, the more frequently an activity is performed results in it taking a
____________ amount of time completing the same activity in the future.

Answer 20

shorter

Question 21

What two methods can be used to determine the critical path of a schedule?

Answer 21

• 1. Two-Pass Method and

* 2. Enumeration Method

Question 22

If an activity on the critical path follows behind schedule, what effect will this have on the entire project?

Answer 22

The end-date for the project will change. Its completion will occur at a later date.

Question 23

A Gantt chart shows each activity’s _______________ and ________________.

Answer 23

• Early start and

* Early finish

Question 24

What is a lag in a project schedule?

Answer 24

a modification of a logical relationship that directs a delay in the successor activity

Question 25

List the main characteristics of a schedule activity. Why is each important?

Answer 25

• It has clear starting and ending points. This is important for everyone to understand exactly what
work is included.
• It results in a tangible output. This is important so everyone will know the activity is complete when
the output is accepted.
• A single person can be held accountable for its completion. This will avoid people blaming each
other for not completing work when it was unclear who should have done it.
• It is possible to establish costs and scheduling for it. This will enable the schedule and budget to be
established and serve as a basis for control

Question 26

Describe the difference between an activity resource estimate and an activity duration estimate.

Answer 26

An activity resource estimate focuses on the type and quantity of resources needed for each activity
while an activity duration estimate focuses on the amount of time that will be needed to complete
each activity.

Question 27

Describe four ways in which a project’s schedule is limited and how to deal with each limitation.

Answer 27

(i). Logical order in which activities need to be completed. Remedies may include:
• Predecessor vs. successor activities
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• Reverse phase schedules
• Leads and lags
• Start-to-start, start-to-finish, finish-to-start and finish-to-finish

(ii). How long each individual activity will take. Remedies may include:
• Methods for estimating durations
• Estimates by people doing the work
• Estimates without initial reference to calendar
• Keeping time units the same
• Optimistic vs. pessimistic estimates
• Adjustments compared to similar projects
• Remedies to problems with estimation
• Omissions
• General uncertainty
• Special case variation
• Common cause variation
• Merging multiple predecessors
• Queuing
• Multitasking
• Student syndrome
• Not reporting early completion of work
• Learning curve

(iii). How many key resources are available when needed. Remedies may include:
• Staffing management plan
• Get key people assigned to project early
• Be imaginative when identifying possible resources
• Pay attention to calendars of key people
• Avoid multitasking key people
• Finish activities early if possible and pass work on

(iv). Imposed dates. Remedies may include:
• Determine how firm dates really are
• Communicate need for relief to sponsor and stakeholders
• Secure powerful support

Question 28

Describe how a WBS and a schedule work together.

Answer 28

• Answers vary, but look for:

• The last row of WBS represents work packages.
• Each work package is composed of one or more activities.
• To generate a schedule from a list of activities
  o Sequence activities
  o Assign resource(s) to each activity
  o Estimate duration of each activity
  o Generate draft project schedule
  o Apply schedule compression methodologies to
  optimize project schedule

Question 29

Label the project duration estimation legend box

Answer 29

ES - - - - - EF
Activity Name
Slack
   Duration
LS - - - - - LF