Pmbok Book Chapter 6

Front 1

Describe the Activity Definition process in the Time Mgmt ka. What are the 2 inputs? What is the output?

Back 1

This process involves the identification of the specific activities that must be performed in order to produce the deliverables of the WBS work packages.

Therefore, the key inputs are:
1. the WBS and
2. the scope statement which includes the project justification and project objectives.

Each of the work packages is then broken down (decomposed) into smaller components called schedule activities. These activities comprise the activity list. Note that decomposition is the tool or technique used in the create WBS process as well.

The primary difference between decomposition in the activity definition process and decomposition in the create WBS process is the final output. In the create WBS process, the results are deliverables; in the activity definition process, the results are activities. In some areas, the WBS and activity list are developed concurrently but in every case, by further breaking down the work, the scope is further refined and could result in WBS updates.

Front 2

Describe the Activity Sequencing process in the Time Mgmt ka

Back 2

Activity sequencing involves organizing project tasks in the order they must be performed. This is accomplished by using the activity list and product description to determine the immediate predecessor(s) and successor(s) of each task.

Front 3

Describe the Activity Resource Estimating process in the Time Mgmt ka. What are the 3 primary outputs?

Back 3

Estimating resources from a skill and availability standpoint

The primary outputs of this process are:
1. the activity resource requirements,
2. the requested changes and
3. the Resource Breakdown Structure (RBS), which is a hierarchical structure of the identified resources broken out by category and type.

Front 4

Describe the Activity Duration Estimating process in the Time Mgmt ka

Back 4

Activity duration estimating is the process of defining the number of work periods that will be needed to complete the individual activities.

Front 5

Describe the Schedule Development process in the Time Mgmt ka. What are 8 necessary inputs?

Back 5

The schedule development process utilizes the duration estimates for each task in order to determine the start and finish dates for each task. By traversing the longest path within the project, the critical path can be determined and the project schedule is developed.

Therefore, necessary inputs to developing the project schedule are
1. the network diagrams with duration estimates,
2. resource requirements,
3. activity list,
4. project and resource calendars,
5. other constraints and assumptions,
6. leads and lags,
7. risk register and
8. attributes of the activities.

Front 6

Describe the Schedule Control process in the Time Mgmt ka. What 3 things does it involve?

Back 6

The schedule control process involves the handling of factors that could impact the project schedule.

It involves:
1. The review and approval processes of changes that lead to schedule changes
2. Determining the size and impact of the change
3. Managing the actual schedule change

Front 7

Describe the Precedence Diagramming Method (PDM). What 4 dependencies does it use?

Back 7

In the Precedence Diagramming Method (PDM), also called Activity-on-Node (AON), boxes or circles are used to represent activities while arrows show the sequence of workflow.

Events (milestones, for example) are not usually shown on PDM diagrams.

Four types of dependencies can be shown:
Finish-to-Start, Finish-to-Finish, Start-to-Start and Start-to-Finish. Finish-to-start is the most common.

PDM is more frequently utilized than the arrow diagramming method since it is easier to read. PDM can also show lead (i.e., negative lag) and lag times.

Front 8

Describe the Arrow Diagramming Method (ADM). What dependency does it use?

Back 8

In the Arrow Diagramming Method (ADM), also called Activity-on-Arrow (AOA), the arrow represents the activities from the WBS and the nodes are events (i.e., completion of the activity) that show the sequence of the activities.

ADM may require "dummy" arrows (activities) to show correctly all sequence relationships.

ADM uses only finish-to-start dependencies.

Front 9

Describe the Conditional Diagramming Method

Back 9

It allows for nonsequential activities such as loops or conditional branches.

Front 10

Describe the Expert Judgment tool/technique for activity duration estimating.

Back 10

Expert Judgment (such as the Delphi Technique): one or more subject matter experts are used as a source for obtaining estimates. If subject matter experts lack historical information or experience, the risk of inaccurate estimates is increased.

Front 11

What are the 2 formulas for the Three-Point Estimating or Triangular Distribution tool/technique for activity duration estimating?

Back 11

1. Mean (μ) = [(a + m + b)]/3
where a = lowest value, m = most likely value and b = highest value
2. Variance and standard deviation
V = σ2
or
V = [(a − b)2 + (m − a)(m − b)]/18

Front 12

Describe the Analogous Estimating tool/technique for activity duration estimating.

Back 12

Analogous Estimating (or Top-Down Estimating): obtained by comparing the current project activities to previous project activities and using the actual duration of the previous similar activity as the basis for the current activity.

The degree of similarity affects accuracy. This technique should be used early in the estimating cycle when there is not much detail known about the activity.

Analogous estimating is considered to be a form of expert judgment.

Front 13

Describe the Quantitatively-Based or Parametric Estimating tool/technique for activity duration estimating.

Back 13

The quantities of the units of work are multiplied by a productivity unit rate to obtain an estimated activity duration.

These estimates are based on historical information that has been codified.

An example is the creation of a training manual in terms of pages per day. A junior writer may produce 2 pages per day while a senior writer may produce 5 pages per day.

A software development example may be the number of lines of code produced per day by various levels of programmers.

Front 14

Describe the Reserve Analysis tool/technique for activity duration estimating.

Back 14

Reserve Analysis (contingency): the additional reserve or buffer time to allow for unexpected delays.

It can be added to the estimated activity duration directly or it can be created as an activity by itself.

It can also be a percentage added to all activities.

It should be increased for projects of high or unknown risk.

Front 15

What are the differences between Weighted-Average and Critical Path Method (CPM) estimating techniques?

Back 15

- Weighted-Average Time
The weighted-average estimate is used in calculating the schedule while the standard deviation is used to compute the probability of schedule completion and provide a range of estimates.

- Critical Path Method (CPM) Estimating uses a single estimate for each activity. The estimate may come from historical data of similar activities, or it may be from expert judgment figures. No standard deviation figure is calculated. CPM estimates are used when there is a high degree of similarity to previous activities.

Front 16

Describe how to perform a Forward Pass

Back 16

The network diagram is traversed from left to right in a Forward Pass to determine ES and EF:
- Start time of the project is zero (0)
- ES = EF of the immediate predecessor
- EF = ES plus duration
- A successor starts when ALL its predecessors are complete
- Project finish date = EF of the final task

Front 17

Define: Float, Total Float, Slack.

Back 17

Float is the amount of time that a schedule activity can be delayed without delaying the end of the project. It is also called Slack or Total Float.

Float is calculated using a Forward Pass (to determine the early start and early finish dates of activities) and a Backward Pass (to determine the late start and late finish dates of the activities). Float is calculated as the difference between late finish date and early finish date. The difference between the late start date and the early start date always produces the same value for float as the preceding computation.

Front 18

What is the impact of Resource Constraints on a project schedule? What 2 methods can be used to facilitate scheduling in this scenario?

Back 18

In many cases projects are resource constrained, which limits optimal scheduling.

Two methods that can be used to facilitate scheduling with limited resources are:
1. resource leveling and
2. critical chain method.

In general these methods typically lengthen the schedule.

**Exam Tip: Resource requirement updates could lengthen a project schedule. If an activity requires 3 people working for 4 calendar weeks but only 2 people are available, it will take 6 calendar weeks to complete the project, all other factors being equal.

Front 19

How do you Finalize Resource Requirements (3 things)?

Back 19

1. Assign resources to each activity, one resource at a time
2. For each time period, sum up the resources required
3. Develop a histogram

Front 20

Define: Crashing

Back 20

Using alternative strategies for completing project activities (such as using outside resources) for the least additional cost. Crashing should be performed on tasks on the critical path. Crashing the critical path may result in additional or new critical paths

Front 21

Define: Critical Chain Method

Back 21

A schedule network analysis technique that is performed after the critical path has been determined to take into account resource availability. The resulting schedule often has an altered critical path.

Front 22

Define: Critical Path. How much float is there in this path (usually)?

Back 22

The path with the longest duration within the project. It is sometimes defined as the path with the least float (usually zero float). The delay of a task on the critical path will delay the completion of the project.

Front 23

Define: Fast Tracking. What does it increase?

Back 23

Overlapping or performing in parallel project activities that would normally be done sequentially.

Fast tracking increases rework and project risk.

Front 24

Define: Hammock

Back 24

Summary activities used in a high-level project network diagram.

Front 25

Define: Lag

Back 25

The amount of time a successor's start or finish is delayed from the predecessor's start or finish.

Front 26

Define: Lead (negative lag)

Back 26

The amount of time a successor's start or finish can occur before the predecessor's start or finish.

In a finish-to-start example, activity A (the predecessor) must finish before activity B (the successor) can start. If a lag of 3 days is also defined, it means that B will be scheduled to start 3 days after A is scheduled to finish. Similarly, a lead of 3 days means that B can be scheduled to start 3 days before A is scheduled to finish.

Front 27

Define: Finish-to-Start logical relationship

Back 27

Where the predecessor must finish before the successor can start. This is the most common relationship and the default for most software packages

**The most common relationship is the finish-to-start relationship. Use other relationships when there is a need for schedule compression.

Front 28

Define: Finish-to-Finish logical relationship

Back 28

Where the predecessor must finish before the successor can finish

Front 29

Define: Start-to-Start logical relationship

Back 29

Where the successor can start as soon as the predecessor starts

Front 30

Define: Start-to-Finish logical relationship

Back 30

Where the predecessor must start before the successor can finish (This is the least used and some software packages do not even allow it.)

Front 31

Define: Predecessor

Back 31

The activity that must happen first when defining dependencies between activities in a network.

Front 32

Define: Project Network Schedule Calculations (3 types)

Back 32

- A forward pass yields early start and early finish dates
- A backward pass yields late start and late finish dates, and
- These values are used to calculate total float.

Front 33

Define: Resource Leveling

Back 33

A schedule network analysis technique that is performed after the critical path has been determined to address specific delivery dates and take into account resource availability or to keep resource usage at a constant level during specified time periods of the project. The resulting schedule often has an altered critical path and could result in the project taking longer to complete.

Front 34

Define: Schedule Activity

Back 34

An element of work performed during the course of a project. It is a smaller unit of work than a work package and the result of decomposition in the activity definition process of project time management. Activities can be further subdivided into tasks.

Front 35

Describe a Gantt Chart type of scheduling chart. What 5 things are they useful for?

Back 35

A bar chart that shows activities against time.

Although the traditional early charts did not show task dependencies and relationships, modern charts often show dependencies and precedence relationships.

These popular charts are useful for:
1. understanding project schedules
2. for determining the critical path
3. for determining time requirements
4. for resource assessments
5. for determining projected completion dates.

Front 36

Describe a A Milestone Chart type of scheduling chart.

Back 36

A bar chart that only shows the start or finish of major events or key external interfaces (e.g., a phase kickoff meeting or a deliverable). It consumes NO resources and has NO duration. These charts are effective for presentations and can be incorporated into a summary Gantt chart.

Front 37

Describe a Network Diagram type of scheduling chart.
What are 2 major diagramming techniques?
What 4 things are these diagrams useful for?

Back 37

A schematic display of project activities showing task relationships and dependencies. The precedence diagramming method (PDM) and the arrow diagramming method (ADM) are the 2 major diagramming techniques.

These diagrams are useful for:
1. forcing the total integration of the project schedule
2. simulations and "what if" exercises
3. highlighting critical activities and the critical path
4. determining the projected completion date.

Front 38

Describe a Time-Scaled Network Diagram type of scheduling chart and 3 things it shows.

Back 38

A combination of a network diagram and a bar chart.
It shows
1. project logic
2. activity durations
3. schedule information.

Front 39

Define: Standard Deviation and its 3 percentages

Back 39

The probability of being within 1, 2 or 3 standard deviations from the mean is the same for the normal distribution and the weighted average or beta distribution. It is important to memorize these percentages.
- 1σ = 68.27%
- 2σ = 95.45%
- 3σ = 99.73%

Front 40

Define: project Mean (μ)

Back 40

The sum of the means of the individual tasks.

Front 41

Define: project Variance

Back 41

The sum of the variances of the individual tasks.

Front 42

Define: project Standard deviation (σ)

Back 42

The square root of the project variance.

Front 43

Define: Successor

Back 43

The activity that happens second or subsequently to a previous activity when defining dependencies between activities in a network.

Front 44

What 3 estimated durations does Triangular Distribution or Three-Point Estimating use, and why is that advantageous?

Back 44

Takes the average of 3 estimated durations —
1. the optimistic value
2. the most likely value
3. the pessimistic value.

By using the average of 3 values rather than a single estimate, a more accurate duration estimate for the activity is obtained.

Front 45

Define: Weighted-Average Time Calculations. When is it most useful?

Back 45

The weighted average places more emphasis on the most likely outcome in calculating the duration of an activity.

Therefore, it produces a bell-shaped curve that is skewed to one side when possible durations are plotted against their probability of occurrence.

A weighted-average estimate is most useful when the project involves activities with little or no previous historical data.

Front 46

Define: What-lf Scenario Analysis. What is the most common simulation method?

Back 46

A technique used to assess the feasibility of the project schedule should unexpected events occur. This analysis is useful for preparing contingency and response plans to mitigate the impact of identified risk events and could involve simulations of various project durations using different sets of project assumptions.

The most common simulation method is the Monte Carlo Analysis technique.

Front 47

What are the 3 time estimate types used in Weighted Average Time Caculations?

Back 47

Calculations use 3 time estimates:
- optimistic (O),
- most likely (ML), and
- pessimistic (P)

to come up with a weighted average (WA) for activity duration.

Front 48

What is the formula for Weighted Average and Weighted Average Standard Deviation?

Back 48

The formula is:
WA (μ) = [O + 4(ML) + P]/6

A standard deviation can also be calculated using the formula:
WA Standard Deviation (σ) = (P − O)/6

Front 49

Describe how to do a Backwards Pass.

Back 49

Once the forward pass is complete, begin the Backward Pass by traversing the network diagram from right to left to determine LF and LS of each task:
- Project LF = EF of the final task of the project
- LS = LF minus duration
- LF = the earliest LS of ALL its successors