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Project Time Management ® Sponsored by Intel PMP ® Team This publication is a derivative work of “A Guide to the Project Management Body of Knowledge” (PMBOK® Guide), which is copyrighted material of and owned by, the Project Management Institute Inc. (PMI ® ), copyright 2004. This publication has been developed and reproduced with the permission of PMI®. Unauthorized reproduction of this material is strictly prohibited. The derivative work is the copyrighted material of and owned by, Intel, copyright 2005. IU Item #: 019727A IU Rev. 3, March 2007
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Project Time Management

®

Sponsored byIntel PMP® Team

This publication is a derivative work of “A Guide to the Project Management Body of Knowledge” (PMBOK® Guide), which is copyrighted material of and owned by, the Project Management Institute

Inc. (PMI® ), copyright 2004. This publication has been developed and reproduced with the permission of PMI®. Unauthorized reproduction of this material is strictly prohibited. The derivative work is the

copyrighted material of and owned by, Intel, copyright 2005.IU Item #: 019727A

IU Rev. 3, March 2007

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Purpose

• Review the Time Management Knowledge Area

• Discuss how TM is represented in the PMP exam

• Offer PMP exam preparation ideas

• Provide references for additional study

“PMBOK” and “PMP” are services and trademarks of the Project Management Institute, Inc. which is registered in the United States and other nations.

This class does not substitute for comprehensive learning and professional experience on this topic. It will not teach

you how to manage time on a project.

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Administration

• There will be no breaks in the two hour sessions. If you need a to take a break, please quietly do so and re-join the presentation.

• Hold all questions to the end. This helps ensure all material gets covered.

• Please limit your questions to the PMBOK®. Intel’s usage (or non-usage) of this material is outside the scope of the presentations.

• Put phone on mute except for asking questions.• We encourage discussion about how Intel uses or

doesn’t use this material outside of the presentations.

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Presentation Materials

• This material is intended for educational purposes only.  The material is based on the information from the PMBOK® and is to be used as a study aid for the PMP exam.  This material is intended to act as a study aid and not to take the place of the PMBOK® which you can purchase from the PMI® website and is required text.  This study aid is provided "As Is" and is not intended to stand alone, but to be used in conjunction with the materials provided and required by the PMI®.  Any student using this as their only material to prepare for the test shall do so at their own risk.  Any reproduction of this material, either internally or externally, is prohibited. 

• http://www.pmibookstore.org

“PMI,” is a trademarks of the Project Management Institute, Inc. which is registered in the United States and other nations.

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Outline

• Why Time Management is important to the project manager

• The Tools and Methods of Schedule Development

• Managing The Schedule

• Major TM processes in the Project Management Lifecycle

• Study tips for Time Management on the PMP exam

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Why Time Management Matters

• In the PMI model, Time is the

only one of the “Triple Constraints”

typically owned by the

Project Manager

• Time Management contains the processes for Schedule Development and Control

• The outputs of Time Management are elements of keen interest in communications to Senior Management and other Stakeholders

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Important Methods & Tools for Schedule Development

• The bulk of information in the Time Management area of knowledge pertains to the systematic creation of the project schedule

• A variety of methods are available to work through these basic steps:

Activity DefinitionActivity Definition Creating a detailed list of the discreet tasks needed to accomplish the project

Activity SequencingActivity Sequencing Determining the best ordering of the defined tasks

Activity Resource Activity Resource EstimationEstimation

Estimating the types and quantities of resources required to perform each schedule activity

Activity Duration Activity Duration EstimationEstimation

Eliciting valid estimates for the time needed to perform each task

Schedule Schedule

DevelopmentDevelopmentSynthesizing individual tasks, durations and dependencies into a holistic view of the project

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• The number and variety of tools used in Time Management often creates confusion among stakeholders

• These next few slides amplify more complex methods and tools that will also be a part of the Tools & Techniques of the Time Management Processes

Important Methods & Tools for Schedule Development (Cont.)

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Important Tools for Schedule Development: Gantt Charts

• A Gantt chart is a time-phased graphical display of activity durations

• It is also referred to as a bar chart

• Weak planning tool, but effective for reporting

• A Gantt Chart is NOT a complete schedule!

Task I.D.sFrom W.B.S.

Task Names from W.B.S. Calendar w/appropriate resolution

Bars showDuration Of tasks

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Important Tools for Schedule Development: Network Diagrams

• A schematic display of the sequential and logical relationships of the activities which comprise a project

• Three common types exist:– Activity On Arrow (AOA)

– Activity On Node (AON)

– Graphical Evaluation and Review Technique (GERT)

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Important Tools: Network Diagrams:

Activity On Arrow Diagrams

• Also called Arrow Diagramming Method

• Circles show start/end of activities

• Arrows represent activities and dependencies

• Only show start to finish relationships

• May use “Dummy” activities– Represented as dotted lines

– Demonstrate additional dependencies

A

E

B

D

C

F

Dummy

ActivityStart Finish

Finish-to-StartThe From activity (A) must finish before the To activity (B) can start

B

A

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Important Tools: Network Diagrams:

Activity On Node Diagrams

• AON is also referred to as the Precedence Diagramming Method (PDM)

• Boxes are used to represent tasks

• Arrows show dependencies

• AON adds additional relationships:Start-to-StartThe From activity (A) must start before the To activity (B) can start

A

B

Start-to-FinishThe From activity (A) must start before the To activity (B) can finish

A

B

Finish-to-FinishThe From activity (A) must finish before the To activity (B) can finish

A

B

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Important Tools: Network Diagrams:

GERT Diagrams

• Very seldom used method (also seldom on PMP exam)

• Only method that allows looping

Activity 1 Activity 2

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Important Tools for Schedule Development: Math Analysis Tools

• Three math analysis tools for duration estimation and/or schedule development are– Critical Path Method (CPM)

– Program Evaluation and Review Technique (PERT)

– Monte Carlo Simulation

• These are VERY prominent in the PMP Exam

• Estimation method questions can be included in both the Planning and Controlling process areas

• All three methods are based on “rolling up” activity durations into a project duration estimate(s)

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Important Tools: Schedule Development:

Critical Path Method

• Estimates project duration by rolling up single estimates of each in-line activity on a precedence diagram

• The path with Zero float (therefore the longest path) is the Critical Path

• The start, end and duration of the Critical Path equals the start, end and duration estimate for the project

• Delays experienced with any activity on the critical path translate directly into delays of the project

• Accelerating non-critical tasks do not shorten the schedule

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Important Tools: Schedule Development:

Critical Path Method (Cont.)

• Let’s look at the Paths:– A+B+C = 7wks– D+E+F = 7wks– D+C = 8wks = Critical Path!

• If the Critical Path is 8 weeks long, the estimated duration of our project is also 8 weeks

A1wk

E1wk

B2wks

D4wks

C4wks

F2wks

Dummy

ActivityStart Finish

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Important Tools: Schedule Development:

Critical Path Method (Cont.)

• Other values calculated in CPM include:– Early Start and Early Finish: the soonest a task can begin or end

– A Forward Pass is used to calculate Early Start and Early Finish

– Late Start and Late Finish: the latest a task can begin of end without effecting the project duration

– A Backward Pass is used to calculate Late Start and Late Finish

– Slack or Float is the difference between the amount of time required for a task and the amount available for it

Late Finish – Early Finish = Slack

or

Late Start – Early Start = Slack

– For The Critical Path: Float = 0, E.S. = L.S. and E.F. = L.F.

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Important Tools: Schedule Development:

Critical Path Method (Cont.)

Forward Pass on A+B+C (EF = ES + Duration – 1)

A1wk

E1wk

B2wks

D4wks

C4wks

F2wks

Dummy

ActivityStart Finish

Task Early Start Duration Early Finish

A Day 1 1wk Day 7

B Day 8 2 wks Day 21

C* Day 29 4 wks Day 56

* Task C is in the Critical Path

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Important Tools: Schedule Development:

Critical Path Method (Cont.)

Backward Pass on A+B+C (LS = LF – Duration + 1)

A1wk

E1wk

B2wks

D4wks

C4wks

F2wks

Dummy

ActivityStart Finish

Task Late Start Duration Late Finish

A Day 8 1wk Day 14

B Day 15 2 wks Day 28

C Day 29 4 wks Day 56

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Important Tools: Schedule Development:

Critical Path Method (Cont.)

Slack/Float on A+B+C yields (Remember that the Critical Path = 8 wks):

A1wk

E1wk

B2wks

D4wks

C4wks

F2wks

Dummy

ActivityStart Finish

Task Float

A 1 wk

B 1 wk

C 0 wk

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A1wk

E1wk

B2wks

D4wks

C4wks

F2wks

Dummy

ActivityStart Finish

ES

1

Duration

7

EF

7

Task ID

A

LS

8

Slack

7

LF

14

ES

8

Duration

14

EF

21

Task ID

B

LS

15

Slack

7

LF

28

ES

29

Duration

28

EF

56

Task ID

C

LS

29

Slack

0

LF

56

ES

1

Duration

28

EF

28

Task ID

D

LS

1

Slack

0

LF

28

ES

29

Duration

7

EF

35

Task ID

E

LS

36

Slack

7

LF

42

ES

36

Duration

14

EF

49

Task ID

F

LS

43

Slack

7

LF

56

Calculations for CPM Exercise:

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Important Tools: Schedule Development:

Critical Path Method: Day 0 Start

Some texts assume a project starts Day 0 instead of Day 1. In this case:

EF = ES + Duration Do not add one to represent the next day's Early Start (ESB = EFA)

Task Early Start Duration Early FinishA Day 0 1 wk Day 7B Day 7 2 wks Day 21C Day 28 4 wks Day 56

Question: Why doesn’t ESC = EFB?

LS = LF - Duration Do not subtract one from the previous days Late Start (LFA = ESB)

Task Late Start Duration Late FinishA Day 7 1 wk Day 14B Day 14 2 wks Day 28C Day 28 4 wks Day 56

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Important Tools: Duration Estimation:

Project Evaluation & Review Technique

• PERT is considered superior to CPM because it uses three estimates of duration (and/or cost) per activity– “Three Point Estimate”

• Calculates start and finish dates from network diagram using a weighted averageweighted average estimate of duration based on the three estimates:

• Optimistic estimate: O

• Most likely estimate: M

• Pessimistic estimate: P

Duration = (O + 4M +P)/6

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Important Tools: Duration Estimation:

Project Evaluation & Review Technique

• A PERT analysis often also includes the following values for each task:

Task Standard Deviation:

Task Variance:

2

6

OP

6

OP

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Important Tools: Schedule Development:

Monte Carlo Simulation

• Computer simulations of a project

• Based on PERT estimates: Optimistic, Pessimistic, Likely

• Provides estimate of overall project risk and probabilities for:– Completing the project on any specific day

– Completing the project for any specific cost

– Any particular task actually being on the critical path

• Will create a project duration more accurate than PERT or CPM

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Important Tools: Schedule Development:Other Key Considerations

Lead & Lag

• Lead: An activity is scheduled to start sooner than its dependency– B is dependent upon completion of A, but it should start 3

days sooner than A’s completion

• Lag: An activity is scheduled to start later than its dependency– As above, but B should start 2 days later

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Important Tools: Activity Sequencing:

Other Key Considerations - Dependencies

• Mandatory Dependencies Inherent in the nature of the work– Like a law of nature

– Example: Pouring the foundation must precede raising the roof

– Also called “hard logichard logic”

• Discretionary Dependencies: Preference of the project planner

• May be determined by best practices or local methodology

• Also called “preferred logicpreferred logic,” “preferential logicpreferential logic,” or “soft logicsoft logic”

• External Dependencies: driven by circumstances or authority outside the project– Example: Need to comply with environmental site survey

regulations before breaking ground

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Important Tools : Schedule Development:Other Key Considerations –

Types of Float/Slack

• Free Float: Amount of time an activity can be delayed without effecting the Early Start of its successor

• Total Float: Amount of time an activity can be delayed without effecting the Project Completion date

• Project Float: Amount of time a project can be delayed without delaying an externally imposed project completion date (e.g. Customer Requested Delivery Date)

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• Given that Scope must remain constant (not always true), there are 3 techniques to shorten a schedule

Important Tools: Schedule DevelopmentOther Key Considerations

Schedule Compression Techniques

Re-EstimatingRe-Estimating Revisit tasks with the most unknowns, eliminate risks and re-calculate the task duration.

CrashingCrashing Add more resources to the Critical Path tasks. This almost always adds cost.

Fast-TrackingFast-Tracking

Where possible, perform Critical Path tasks in parallel that were originally in series. Fast-tracking often results in re-work, usually increases risk and requires more intensive communications.

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Important Tools: Duration Estimation:

Other Key Considerations – Hammocks

• An activity whose duration varies depending upon the actions of its predecessor and successor activities

• A summary activity

A

B

CHammock

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Managing the Schedule:

Schedule Change Control

• A vital responsibility of the Project Manager

• Detailed in the Schedule Management Plan

• Part of overall change control

• Insures that schedule changes are:– recognized

– evaluated for overall benefit

– approved

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Managing the Schedule:

Schedule Control• Managing the schedule involves following the Control

Cycle:– Create a plan

– Execute the plan

– Compare actual results to planned results at checkpoints along the way

– Make course corrections (change plan as required)

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Managing the Schedule:

Create a Plan• The Schedule is the “plan”

• Work package start and finish dates define duration for work packages

• Network diagram spreads the work package durations over the life of the project

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Managing the Schedule:

Execute the Plan

• The team performs the activities in the work packages

• This is the product-oriented work (requirements, design, code, test, etc.) plus the level of effort work packages.

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Managing the Schedule:

Compare Actuals to Plan• Periodic checkpoints:

– Time oriented (e.g., monthly)

– Event oriented (e.g., milestone)

• The PM collects the actual start and finish dates

• Compare actual dates to plan dates

• Difference is called a VarianceVariance

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Managing the Schedule:

Causes of Schedule Variances

• Took longer than expected (estimatingestimating problem)

• Required unanticipated tasks (scope scope or activity activity definitiondefinition issue)

• Resources pulled off to do other work (prioritiespriorities problem)

• Time used putting out fires (riskrisk management)

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Managing the Schedule:

Make Course Corrections• Analyze variances to understand cause• Formulate a plan to get back on schedule (a “Get Get

Well Plan” Well Plan” or a “Recovery Plan” “Recovery Plan”) • Possible recovery actions:

– Reassign work– Fast tracking or crashing– Work overtime– Scope change (de-scope, split scope)

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Managing the Schedule:

Performance Measurement Tools

• Trending, forecasts, and “what if” Analysis

• Variance analysis

• Project Management Software– Usually good for pointing out variance

– Not of much value for understanding what happened

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The TM Processes

• PMI identifies 6 key processes that are associated with the Time Management Knowledge Area

• All but one are processes in the Planning Phase of the Project Lifecycle (Schedule Control, 6.6, is a Controlling Phase process )

• The planning processes are conducted in sequence and iterated

• Since these are often included in the PMP exam, it is valuable to discuss them here

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The TM Processes (cont.)

Activity Definition

Activity ResourceEstimating

ScheduleDevelopment

Activity Sequencing

ScheduleControl

Time ManagementTime ManagementProcessesProcesses

Activity Duration Estimating

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The TM Processes:

Activity Definition (6.1)

• One of the earliest processes of the planning phase

• WBS work packages are decomposed into schedule activities

• Requires the participation of the project team and coordination of the project manager

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The TM Processes: Activity Definition (6.1):

Inputs• Enterprise Environmental Factors (4.1.1.3)

– Availability of PMIS and Scheduling Software Tools

• Organizational Process Assets (4.1.1.4)– Historical Information / Lessons Learned knowledge base

– Policies, Guidelines, Procedures

• Project Scope Statement (5.2.3.1)– Constraints – outside limiting factors – Assumptions – factors that are considered to be true, but not

confirmed

• Work Breakdown Structure (5.3.3.2)• WBS Dictionary (5.3.3.3)• Project Management Plan

– Contains the Schedule Management Plan

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The TM Processes: Activity Definition (6.1):

Tools &Techniques• Decomposition

– Subdividing work package deliverables into schedule activities(WBS = Scope where Activity Definition = Time)

– Level of decomposition depends on complexity, novelty of project, and experience of team

• Templates– Sample formats from previous projects– Provides insight into resource skills, risks, levels of effort, etc.

• Rolling Wave Planning (a form of progressive elaboration)• Expert Judgment

– From within and outside the project team• Planning Component

– Control Account– Planning Package

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The TM Processes: Activity Definition (6.1):

Outputs

• Activity List– Contains ALL activities to be performed on the project

– Includes descriptions understandable to the team

• Activity Attributes– Identify multiple attributes associated with each schedule

activity

• Milestone List– List also indicates whether the milestone is mandatory or

optional

• Requested Changes– Changes can affect project scope statement or WBS

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The TM Processes:

Activity Sequencing (6.2)

• A Planning Process

• Identifying and documenting relationships among activities defined in (6.1)

• Some sequencing can be done with PM software

• Requires the participation of the project team

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The TM Processes: Activity Sequencing (6.2):

Inputs• Project Scope Statement (5.2.3.1)

• Activity List (Outputs of 6.1.3.1)

• Activity Attributes (6.1.3.2)

• Milestone List (6.1.3.3)

• Approved Change Requests (4.4.1.4)

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The TM Processes: Activity Sequencing (6.2):

Tools &Techniques

• Precedence Diagramming Method (AON described

earlier)

• Arrow Diagramming Method (AOA described earlier)

• Schedule Network Templates (standardized) – More common for processes that are nearly identical

– Clinical Trials, Tract House Construction

– Most often feasible for subnets (portions of the network)

• Dependency Determination

• Applying Leads and Lags

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The TM Processes: Activity Sequencing (6.2):

Outputs

• Project Network Diagrams– Schematic display of the project’s activities and the logical

relationships (dependencies) between them

– Should be accompanied by a narrative describing the approach used

– Any unusual sequences should be fully described

• Updates to the Activity List and Activity Attributes– Omissions and errors discovered during sequencing

– Often referred to as “Refinements”

• Requested Changes

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The TM Processes:

Activity Resource Estimating (6.3)

• A planning phase process

• Involves determining:– What resources are required

– What quantities of each resource will be used

– When each resource will be available

• Is closely coordinated with the Cost Estimating (Section 7.1)

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The TM Processes: Activity Resource Estimating (6.3):

Inputs• Enterprise Environmental Factors (4.1.1.3)

– Infrastructure resource availability information

• Organizational Process Assets (4.1.1.4)– Policies regarding staffing, renting, and purchasing

• Activity List (6.1.3.1)

• Activity Attributes (6.1.3.2)

• Resource Availability (9.2.3.2 and 12.4.3.4)– Availability is used for estimating resource types

• Project Management Plan (4.3)– Schedule Mgmt Plan is a component of the PMP

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The TM Processes: Activity Resource Estimating (6.3):

Tools &Techniques• Expert Judgment

– Groups or persons with specialized knowledge should be used to assess resource-related estimates

• Alternative Analysis– Examine substitute capabilities, different types of machines,

make-buy decisions

• Published Estimating Data– Trade information on Production Rates, Unit Costs

• Project Management Software– Helps plan, organize, manage resource pools, and develop

resource estimates

• Bottom-up Estimating– Resource needs of detailed work are estimated and then

aggregated into a total quantity for the activity

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The TM Processes: Activity Resource Estimating (6.3):

Outputs

• Activity Resource Requirements– Description of the types and quantities of resources required for each

schedule activity in the work package– Basis of Estimates – documented assumptions and methods used for

estimates, availability and quantity

• Activity Attributes (Updates)– Types and quantities of resources are incorporated in the attributes

• Resource Breakdown Structure– Hierarchy of resources by resource category and type

• Resource Calendar (Updates)– Composite calendar containing working days for a resource– Resource specific holidays and availability periods– Provides quantity of resource available during a period

• Requested Changes

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The TM Processes:

Activity Duration Estimating (6.4)

• A Planning Phase process

• Involves using scope and resource information to estimate durations for the activities of the project

• Estimates usually originate from project team members most familiar with the activity then progressively elaborated

• Requires the participation of the project team, typically for development, but always for approval, of estimates

• Although a summation of durations can be made, it does not constitute a project duration estimate, which is an output of Schedule Development (6.5)

• All estimates should use a common work unit/period

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The TM Processes: Activity Duration Estimating (6.4):

Inputs• Enterprise Environmental Factors

– e.g., commercial databases

• Organizational Process Assets (4.1.1.4) – Historical information

• Project Scope Statement (5.2.3.1)– Constraints and assumptions

• Activity List ( 6.1.3.1) and Activity Attributes (6.1.3.2)

• Activity Resource Requirements (6.3.3.1)– Number and skill of assigned resources

• Resource Calendar (6.3)

• Project Management Plan– Risk Register: identified risks to consider when making the estimate

– Activity Cost Estimates: useful for estimating (if completed)

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The TM Processes: Activity Duration Estimating (6.4):

Tools &Techniques• Expert Judgment

– Expert judgment, guided by historical information should be used whenever possible

– Absence of expert judgment constitutes a project risk• Analogous Estimating “Top-Down Estimating”

– Using durations from previous projects to predict future ones– Uses historical information and Expert Judgment

• Parametric Estimating– Quantity of work times the productivity rate

• Three-Point Estimates– Most Likely, Optimistic, Pessimistic– Estimate constructed using an average of the three points

• Reserve Analysis– Reserve (Contingency) Time “Buffer” or “Fudge Factor”– A period held in reserve in recognition of schedule risk

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The TM Processes: Activity Duration Estimating (6.4):

Outputs

• Activity Duration Estimates – quantitative estimates of the likely number of work periods required to complete an activity– Should include a range of possible results “+ or –” or “%

probability”

• Activity Attributes (Updates)– Updated to include durations for each activity, assumptions,

and contingency reserves

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The TM Processes:

Schedule Development (6.5)

• A Planning Phase process

• Determining the Start and Finish dates for project activities

• Normally a highly iterative process

• A relatively complex process with considerable inputs to sort and consider

• Produces one of the most vital and visible project management documents

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The TM Processes: Schedule Development (6.5):

Inputs

• Organizational Process Assets (4.1.1.4)

• Project Scope Statement (5.2.3.1)

• Activity List (6.1.3.1)

• Activity Attributes (6.1.3.2)

• Project Network Diagrams (6.2.3.1)

• Activity Resource Requirements (6.3.3.1)

• Resource Calendars (6.3.3.4)

• Activity Duration Estimates (from 6.4.3.1)

• Project Management Plan

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The TM Processes: Schedule Development (6.5):

Tools & Techniques• Schedule Network Analysis

– The technique of identifying early start / finish dates and late start / finish dates for uncompleted portions of project schedule activities

– Includes CPM, CCM, What-if-Analysis, and Resource Leveling• Critical Path Method (CPM)

– Calculates theoretical early start & finish and late start & finish without regard to resource limitations

– Perform forward & backward pass analysis through network paths– Activities on the Critical Path contain zero float

• Schedule Compression– Crashing and Fast-Tracking

• What-if Scenario Analysis– Used to assess the schedule feasibility under adverse conditions

and prepare contingency & response plans– Monte Carlo Analysis

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The TM Processes: Schedule Development (6.5):

Tools & Techniques (cont.)• Resource Leveling

– Network analysis technique for evening out resource usage• Critical Chain Method (CCM)

– Network analysis technique to account for limited resources– Determines the “Altered Critical Path”

• Project Management Software– Automate mathematical analysis and resource leveling

• Applying Calendars– Project calendars (4.1.1.4) and resource calendars (6.3.3.4)

• Adjusting Leads and Lags– Used in network analysis to produce a viable schedule

• Schedule Model– Compiled schedule data and associated tool

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The TM Processes: Schedule Development (6.5):

Outputs• Project Schedule

– Must have (at least) planned start and finish dates for each activity– Schedule is considered preliminary until resources have been

assigned and confirmed– Can be presented in tabular for or in graphical formats such as:

– Network Diagram: usually show NW logic and critical path activities– Bar/Gantt Charts: frequently used for management presentations– Milestone Charts: only used for summary communications

• Schedule Model Data– Includes at least milestones, activities, attributes, assumptions and

constraints– May include resource histogram, alternative schedules, and

contingency reserves• Schedule Baseline – Accepted and approved by project

management tool • Resource Requirement (Updates) – especially after resource

leveling

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The TM Processes: Schedule Development (6.5):

Outputs (cont)• Activity Attribute (Updates)

– Revisions generated during schedule development

• Project Calendar (Updates)

• Requested Changes– From the schedule development process

• Project Management Plan (Updates)– Schedule Management Plan may need to be updated to

reflect approved changes

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The TM Processes:

Schedule Control (6.6)

• A Controlling phase process• Determine current status and changes to the

project schedule• Concerned with influencing factors that

create schedule changes to assure that they are agreed upon

• Management of actual changes as they occur• Must be thoroughly integrated with the other

Control Processes

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The TM Processes: Schedule Control (6.6):

Inputs• Schedule Management Plan (PMP 4.3)

– Establishes how the schedule will be managed and controlled

• Schedule Baseline (6.5.3.1)– Approved schedule used for measuring and reporting

schedule performance

• Performance Reports (10.3.3.1)– Allow for monitoring schedule compliance

– May alert the team to potential issues

• Approved Change Requests (4.4.1.4)– Changes may require extending or accelerating the schedule

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The TM Processes: Schedule Control (6.6):

Tools &Techniques• Progress Reporting

– Use actual start dates, actual finish dates and remaining durations

– Use earned value to assess the magnitude of schedule variations

• Schedule Change Control System– Defines the procedures for changing the schedule

– Part of Integrated Change Control process (4.6)

– May include: tracking systems, approval schemes, etc.

• Performance Measurement (7.3.2)– Schedule Variance (SV) and Schedule Performance Index (SPI)

• Project Management Software for tracking

• Variance Analysis (comparing actual with schedule targets)

• Schedule Comparison Bar Charts– Actual vs. baseline

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The TM Processes: Schedule Control (6.6):

Outputs• Schedule Model (Updates)

– Any modification to the schedule used to manage the project

– Revisions are generally caused by scope change

• Schedule Baseline (Updates)– Re-baseline only if approved changes are significant

• Performance Measurements– Calculated SV and SPI for work packages and control accounts

• Requested Changes– Disposition via the Integrated Change Control Process (4.6)

• Recommended Corrective Action– Anything done to bring future performance back in line with the

baseline, instead of rebaselining

– Frequently requires root cause analysis

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The TM Processes: Schedule Control (6.6):

Outputs (cont)• Organizational Process Assets Updates

– Lessons Learned documentation of the causes of variance and the reasoning behind the response

– Becomes part of an historical database used in future projects

• Activity List Updates

• Activity Attributes Updates

• Project Management Plan Updates – Updated to reflect any approved changes resulting from

Schedule Control

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Study Tips: Time Management Management

• Time Management is currently the 2nd most difficult knowledge area on the PMP exam – Know it thoroughly

• Know the variations of Network Diagramming AND how they differ

• Memorize formulas for PERT and CPM• Remember that PERT, CCM and CPM are methods

while AOA and AON are diagrams• Understand Crashing and Fast-Tracking • Memorize the relationships between tasks and the

types of dependencies• Write down formulas and definitions after sitting

down in the testing station

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Conclusions

• Time Management is a vital element of the Planning Phase

• The final objective of the TM Processes is to develop and manage a realistic project schedule

• The TM Processes intersect frequently with Scope, Communications and Integration processes. One must understand the differences

• Many of the TM processes must be reiterated throughout the course of the project

• Many of the outputs from TM processes should be archived for the benefit of future projects

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Time Management Web Links

• http://www.gantthead.com/article.cfm?ID=99790 -an article on TM and PMP prep

• http://www.columbia.edu/~jm2217/Q7503_5post.ppt - a nice class on Scheduling

And don’t forget the PMI online Knowledgebase:• http://knowledgebase.pmi.org/content/frame.htm

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Acknowledgements

• PMI® PMBOK®

• PMI® http://www.pmi.org/• Mid Carolina Chapter of PMI®

• PMP Exam Prep, Rita Mulcahy, PMP RMC Publications, Inc.

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Online Resources• PMP Study Group Series Website

– From Circuit > Employee Services > Training and Development > Employee Development and Education > Coaching & Developing Employees > Employee Development > Professional Development > Project Management> PMP Study Group Series

• PMP Tips and Tools– Suggestions from Intel PMP’s on preparing for and taking the exam. Tools to record your

educational and experience requirements.• PMP Exam Practice Questions

– Test exam is available to Intel employees through the Skillsoft training portal. Within the Skillsoft site, from the Catalog (top nav bar), select Project Management > PMP Exam Practice Questions. * This link takes you to IU Webpage first. After you agree on $95 annual subscription fee, please click on the Log in link to the SkillSoft and Books24x7 portal.

– You can take the exam in study mode and receive feedback per answer, or take it in test mode to see how you score in each category. There is no limit to the number of times you can access this test exam.

• PM Learning Resources Center– This website has been designed to be your interface to all of the Intel-wide training and

learning resources. We seek to assist you in taking ownership of your career by providing all of the professional development resources necessary for you to assess, develop, and refresh your increasing range of PM skills whether you are just starting as a project coordinator or are a certified project manager. Simply select the stage of development that best matches your interests.

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Back-up Slides

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Review of WBS Concepts

• WBS = Work Breakdown Structure

• The WBS is:– the primary input into activity definition

– a deliverables-oriented grouping of project elements

– defines and organizes the total scope of the project

• Work not in the WBS is out of scope

• Work packages are the lowest level of the WBS

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Activity Sequencing Precedence Sample

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Danglers

• An activity that lacks either a predecessor or a successor

• “Start” and “Stop” are both danglers

• When a dangler occurs, investigate the cause

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Project Scheduling Software Duration Algorithm

• EffortEffort: E in labor hours

• ProductivityProductivity: P in efficiency factor

• AvailabilityAvailability: A in hours/person/day

• Number of WorkersNumber of Workers: N

• Duration = ((E/P)/A)/N

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Effort-Driven Estimate Example

• Task requires 80 hours effort• Two average workers are assigned (average

experience equals 1.0)• Each person can devote 4 hours per day• Duration = [(80/1.0)/4]/2 = 10 days• Assumes they work in parallel:

– Person A: 4,4,4,4,4 4,4,4,4,4 = 40– Person B: 4,4,4,4,4 4,4,4,4,4 = 40

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PERT Calculation

• Uses three estimates of duration (and cost) per activity:– Best case, worst case, most likely case

• Calculates start and finish dates from network diagram using a weighted averageweighted average estimate of duration based on the three estimates

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PERT: Beta Distribution

• Simplified version of Normal DistributionNormal Distribution

• Takes into account probabilistic nature of activity durations

• Calculates a weighted average approximation of the mean

• Also has an approximation of the standard deviation

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What is Standard Deviation?

• Measures variability (i.e., dispersion)

• Represented by Greek letter sigma ( )

• Under normal distribution, approximate values of standard deviation:– 1 each side of mean: 68% of outcomes

– 2 each side of mean: 95% of outcomes

– 3 each side of mean: 99% of outcomes

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Schedule Development

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PERT Activity Duration

• Optimistic estimate: B

• Most likely estimate: M

• Pessimistic estimate: W

Duration = (B + 4M +W)/6

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Activity Standard Deviation

• Standard deviation = (B - W)/6• Where did 6 come from?

– 3 each side of mean (3+3 = 6)– Implies 99% coverage– (If task executed 100 times, 99 fall within range)

• Best and Worst case estimates:– 1 time in 100 for each

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Resource Requirements

• Activity duration is affected by availabilityavailability of resources, e.g., if a programmer is available full time or only half time

• Activity duration is affected by resource skillskill levels, e.g., if the programmer is highly experienced or junior

• Activity durations may need to be estimated iteratively because of resource impact

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Resource Pool Description

• Implies infrastructure for scheduling

• Fits within matrix management assumption

• Recognizes the potential bottleneck on projects (“resource constrained”)

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Critical Path Method

• Uses single point estimate of duration per activity

• Calculates start and finish dates from network diagram using the single point duration estimate

• Calculates floatfloat (also known as slackslack) in the schedule

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Critical Path

• Path with least (usually zero) float• Calculated using either single point or PERT

weighted average estimate• Delays experienced with any activity on the critical

path translate directly into delays of project completion date

• Near Critical Path: Path with very small float (slight delay can shift critical path)

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Calculating the Critical Path

• Start with the network diagram

• Assign durations to each activity

• Forward pass (earliest start and finish for each activity)

• Backward pass (latest start and finish for each activity)

• Identify path with least float

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Standard Deviation of the Critical Path

• Variability of the project’s end date

• Gives an (incomplete) idea of schedule risk

• Available only with PERT estimates, not single point

• Formula: Square root of the sum of the squares of each individual critical path activity’s standard deviation:

( 2 + 2 + … + 2 )

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Limitations of CPM

• Resource Availability

• Fixed Dates

• Elapsed Duration Tasks

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Resource Availability

• CPM assumes resources are infinitely available

• Delays can occur on the critical path when resources are in short supply

• Prioritizing resources: Assign resource to the path with the least slack

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Resource Critical Path

• RCP is the sequence of tasks that determines the project end date, taking into account resource availability

• RCP must be considered for organizations that cannot easily add and release resources during the project

• Altered Critical Path

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Elapsed Duration Tasks

• Some tasks’ durations are a function of elapsed calendar time rather than business hours– Examples: Paint drying, concrete curing

• Scheduling software may not take this into account without manual intervention

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Calculating Float

• Perform forward pass through network diagram:– Determine early start (ES) and early finish (EF)

dates for each activity• Perform backward pass through network diagram:

– Determine late start (LS) and late finish (LF) dates for each activity

• Difference between dates is float:– Total Float– Free Float

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Total Float• The amount of delay a work package can have without affecting the

project’s final completion date:

LF(late finish) minus EF(early finish)

orLS(late start) minus ES(early start)

Calculated with respect to a given (single) activity

LS FF LF

ES TF EF

11 FF 14

09 02 12

ActivityDuration

LF (14) – EF (12) = 02

or

LS (11) – ES (09) = 02

ActivityDuration

TF(total float) =

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Free Float• The amount of delay a work package can have without affecting

the start of the next activity

ES(early start) of succeeding activity minus EF(early finish) of preceding activity

Subtract one from the calculationwhen the next activity always starts on the next day, free float is 8 – 1 = 7(e.g., if F2 ended day 9 and G6started day 10, then 10 – 9 = 1 but there really is no slack, it’s zero, 1 –1 = 0)

LS FF LF

ES TF EF 8 7 9

15 7 16

17 0 22

17 0 22

F G2 6

Free Float = ES(succeeding) (17) – EF (preceding) (09) = 8 (-1)

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Forward and Backward Passes

• Calculating through the network the dates by which each activity must start

• Forward pass: Determines the earliest dates for activities to start and finish

• Backward pass: Determines the latest dates for activities to start and finish

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Perform Forward Pass, Backward Pass, and Calculate CP and Float Values

ES TF EF

LS FF LF

A

5

ES EF

LS LF

TF

FF

LS FF LF

ES TF EFES TF EF

LS FF LF

LS FF LF

ES TF EF

ES TF EF

LS FF LF

LS FF LF

ES TF EF

B

C

D

E

F

G

3

2

4

7

2

6

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Results of Forward Pass

6 7

A

5

6 8

6 91 5

10 16

8 9

17 22

B

C

D

E

F

G

3

2

4

7

2

6

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Results of Backward Pass

6 7

13 14

A

5

6 8

7 9

6 9

6 91 5

1 5

10 16

10 16

8 9

15 16

17 22

17 22

B

C

D

E

F

G

3

2

4

7

2

6

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Schedule Exercise

200

ENGINEERING

DESIGN

18

ES=LS=

300

ENGINEERING

REVIEW

15

400

MOBILIZESITE

20

450

SOLICIT SUBS14

500

OBTAINPERMITS

25

600

POUR

CONCRETE

29

ACTIVITY ID

ACTIVITY

DESCRIPTION ACTIVITYDURATION

TOTALFLOAT

LEGEND

ES=LS=

EF=LF=

ES=LS=

ES=LS=

ES=LS=

ES=LS=

ES=LS=

EF=LF=

EF=LF=

EF=LF=

EF=LF=

EF=LF=

350

PREMOBILIZATION

5

ES=LS=

EF=LF=

EF=LF=

650

CONSTRUCT SHELL

14

ES=LS=

EF=LF=

FORWARD PASS = ES + DURATION =EF

BACKWARD PASS = LF - DURATION =EF

START AT T =

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Schedule Exercise Answers

200

ENGINEERING

DESIGN

18

ES=1LS=1

300

ENGINEERING

REVIEW

15

400

MOBILIZESITE

20

450

SOLICIT SUBS14

500

OBTAINPERMITS

25

600

POUR

CONCRETE

29

ACTIVITY ID

ACTIVITY

DESCRIPTION ACTIVITYDURATION

TOTALFLOAT

LEGEND

ES=24LS=28

EF=43LF=47

ES=19LS=19

ES=34LS=34

ES=19LS=23

ES=LS=

ES=48LS=48

EF=76LF=76

EF=47LF=48

EF=43LF=47

EF=33LF=33

EF=LF=

350

PREMOBILIZATION

5

ES=19LS=23

EF=23LF=27

EF=18LF=18

0000

4

44

650

CONSTRUCT SHELL

14

ES=77LS=77

EF=90LF=90

0

FORWARD PASS = ES + DURATION - 1 = EF

BACKWARD PASS = LF - DURATION + 1 = LS

START AT T = 1

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Total Float Calculation

Activity

Duration

Early Start Early Finish

Late Start Late Finish

Total Float: EF - LF

Total Float: ES - LS

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Free Float Calculation

Activity A

Duration

Activity B

Duration

Early Finish Early StartFree Float

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Results of Calculation of CP(critical path) and Float Values

6 7 7

13 0 14

A

5

6 1 8

7 1 9

6 0 9

6 0 91 0 5

1 0 5

10 0 16

10 0 16

8 7 9

15 7 16

17 0 22

17 0 22

B

C

D

E

F

G

3

2

4

7

2

6

TFTF

FF

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Schedule Change Control System

• Defines procedures to be followed when changing project schedule

• Establishes approval levels, documentation required, and procedural steps to follow

• Described in the Schedule Management Plan or by references to an external process

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Schedule Change Control Issues

• Scope CreepScope Creep problem• Schedule impact must accompany scope change• Guide discusses change control processes

separately for:– Scope– Schedule– Cost

• PMBOK® chapter 4 integrates these in Overall Change Control