Dr. Cornel Collins, MBA, CHt, BCSH, FAAPM, CIPM, MPM, CPM, CEC, CLC
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The PMBOK® states that Project Time
Management is the Knowledge Area that
“includes the processes required to accomplish
timely completion of the project.”
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Monitoring &
Controlling Processes
Planning
Processes
Enter phase/
Start project
Initiating
Processes
Closing
Processes
Exit phase/
End project
Executing
Processes
Knowledge Area
Time
Management
Process
Initiating
Planning
Define Activity
Sequence Activity
Activity Resource Estimating
Activity Duration Estimating
Schedule Development
Executing
Monitoring & Control
Schedule Control
Closing
Urgent
Not Urgent
Quadrant I Activities
• Crisis
• Pressing Problems
• Deadline Driven Deliverables
Quadrant II Activities
•
•
•
•
Quadrant III Activities
•
•
•
•
•
Interruptions, some calls
Some mail, some reports
Some meetings
Proximate, pressing matters
Popular Activities
Dr. Stephen Covey, 7 Habits of Highly Effective People
Prevention
Relationship building
Recognizing new opportunities
Planning
Quadrant IV Activities
•
•
•
•
Trivia, busy work
Some mail, some calls
Time wasters
Pleasant Activities
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• Activity definition: Identifying the specific activities that the
project team members and stakeholders must perform to
produce the project deliverables.
• Activity sequencing: Identifying and documenting the
relationships between project activities.
• Activity resource estimating: Estimating how many
resources a project team should use to perform project
activities.
• Activity duration estimating: Estimating the number of work
periods that are needed to complete individual activities.
• Schedule development: Analyzing activity sequences, activity
resource estimates, and activity duration estimates to create
the project schedule.
• Schedule control: Controlling and managing changes to the
project schedule.
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 Involves identifying and documenting the
work that is planned to be performed
 This process identifies the deliverables at
the lowest level of the work breakdown
structure (WBS), called the work package
 The work package is then broken down
into smaller components called schedule
activities
*These provide a basis for
estimating, scheduling,
executing, and monitoring and
controlling the project work
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INPUT
Tools & Techniques
OUTPUT
Activity List
Project Management Plan
Expert Judgement
Activity Attributes
Enterprise Environmental
Factors
Decomposition
Milestone Lists
Organizational Process Assets
Rolling Wave Planning
Change Requests
Meetings
Projects Documents Updates
Change Requests
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

An activity or task is an element of work normally
found on the WBS that has an expected duration,
a cost, and resource requirements.
Project schedules grow out of the basic
documents that initiate a project.
 The project charter includes start and end dates and
budget information.
 The scope statement and WBS help define what will be
done.

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.
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
The Project Management Plan contains the
schedule management plan, which provides
guidance on the development and planning of
schedule activities.

Decomposition: The process of subdividing the
project work packages into smaller, more
manageable components called schedule
activities.
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Rolling Wave Planning
• A form of progressive elaboration planning where the
work to be accomplished at the near term is planned
in detail at a low level of the WBS, while the work far
in the future is planned at relatively high levels of the
WBS.
Templates
• A standard activity list or a portion of an activity list
from a previous project can often be used as a
template.
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• An activity list is a tabulation of activities to be included
on a project schedule. The list should include:
– The activity name
– An activity identifier or number
– A brief description of the activity
• Activity attributes provide more information about each
activity, such as predecessors, successors, logical
relationships, leads and lags, resource requirements,
constraints, imposed dates, and assumptions related to
the activity.
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• A milestone is a significant event that normally has no
duration.
• Milestones are typically major accomplishments of the project
and mark the completion of major deliverables or some other
key event in the project.
• It often takes several activities and a lot of work to complete a
milestone.
• Milestones are useful tools for setting schedule goals and
monitoring progress.
• Examples include completion and customer sign-off on key
documents and completion of specific products.
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INPUT
Tools & Techniques
OUTPUT
Project Management Plan
Precedence Diagram
Methods
Project schedule network
diagrams
Enterprise Environmental
Factors
Dependency Determination
and integration
Projects Documents Updates
Organizational Process Assets
Leads and lags
Project Documents
Project Information Systems
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• Involves reviewing activities and determining
dependencies or relationship between
activities .
• A dependency or relationship relates to the
sequencing of project activities or tasks.
• You must determine dependencies in order
to use critical path analysis.
• Can be performed by using manual or
automated techniques or project
management software
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Three types of dependencies:
• Mandatory dependencies
• Discretionary dependencies
• External dependencies
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• Mandatory dependencies: Also referred to as hard
logic Required as per contract or inherent in the nature
of the work. Usually involve physical limitations (e.g.,
you cannot build the ceiling until walls are constructed)
Are determined by the project management team
during the activity sequencing process.
• Discretionary dependencies: Also referred to as
preferred logic, preferential logic, or soft logic Are
determined by the project management team during the
activity sequencing process Should be used with care
and well documented, since they may limit later
scheduling options.
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• External dependencies: Are determined by the
project management team during the activity
sequencing process. Involve a relationship
between project and non-project activities such as
activities outside the project team’s control (e.g.,
dependence on external sources for deliveries,
environmental factors governed by statutes, etc
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• 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 Arrow and
Precedence diagramming methods.
•
•
•
•
Uses arrows to represent activities
Connects activities with nodes
Uses only finish-to-start dependencies
May require dummy activities to define relationships
Note: The network diagram in it’s pure sense just shows logical
relationship between activities.
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•
•
•
•
•
Activities are represented by boxes/ rectangles.
Arrows show relationships between activities
More popular than ADM method as used by PM software
Better at showing different types of dependencies
In PDM, finish-to-start is the most common relationship
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Includes four types of dependencies or logical
relationships:
– Finish-to-start (FS)
– Finish-to-finish (FF)
– Start-to-start (SS)
– Start-to-finish (SF)
The PDM is also called Activity–On-Node (AON) and it
does not use dummy activities nor does it allow for
loops or conditional branches.
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A Lead may be added to start an activity
before the predecessor activity is finished.
e.g. Furniture may be installed 2 weeks
prior to completion of painting (Finish to
start relationship with 2 weeks lead)
Lag introduces waiting period between
activities. Lag introduces a delay in the
successor activity. e.g. Needing to wait
three days after pouring concrete before
constructing the frame for a house.
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1. Project Schedule Network Diagrams :
• It can be produced manually or by using a project
management software
• Project Schedule Network Diagrams are not final
schedule For the exam, know that, in its pure form,
the network diagram shows just dependencies.
2. Project Document Updates
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• Before estimating activity durations, you must have
a good idea of the quantity and type of resources
that will be assigned to each activity.
• Consider important issues in estimating resources:
– How difficult will it be to complete specific
activities on this project?
– What is the organization’s history in doing similar
activities?
– Are the required resources available?
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• All projects, from the smallest to the largest, require
resources. Before estimating activity durations, you
must have a good idea of the quantity and type of
resources that will be assigned to each activity
• The term resources in this case does not mean just
people; it means all the physical resources required
to complete the project.
• People
• Equipment
• Materials
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Resource Calendars( Input)- is a calendar that is used to reflect
specific working hours, vacations, leaves of absence, and planned
personal time for individual resources. Resource calendars can be
used for human resources as well as equipment.
Alternative Analysis (Tool & Technique)-is used when thinking about
the methods you might use to accomplish the activities your
resources have been assigned. Many times, you can accomplish an
activity in more than one way, and alternatives analysis helps decide
among the possibilities.
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Published Estimating data- Estimating data may
include organizational guidelines, industry rates or
estimates, production rates, and so on.
Bottom Up Estimating-Bottom-up estimating is
A process of estimating individual schedule
activities or costs and then adding these
together to come up with a total estimate for the
work package.
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Activity Resource Requirements – Activity resource
requirements provide an estimate of the type and quantity
of resources needed to complete activities. The Schedule
Development process considers when the required
Resources will be used.
Resource Breakdown Structure (RBS) - The Resource
Breakdown Structure (RBS) displays the hierarchical
structure of the categories and types of resources needed.
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The RBS Chart shows you the hierarchy of your resource pool in a
hierarchical tree.
An important feature of this view is that the Cost and Budget (baseline
cost) values roll up into parent resources.
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• You use the inputs and tools and techniques to establish
these estimates. Activity duration estimates are an
estimate of the required work periods needed to
complete the activity. This is a quantitative measure
usually expressed in hours, weeks, days, or months.
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• Here the network diagram is updated by estimating duration
for each activities.
• The Activity Duration Estimating process attempts to estimate
the work effort and number of work periods needed to
complete each schedule activity.
•
A person or team most familiar with work of the project shall
estimate duration to make it more accurate.
• All data and assumptions used for estimation shall be
documented for future analysis (remember this, we need this
information during the risk management process)
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• Duration includes the actual amount of time
worked on an activity plus the elapsed time.
• Effort is the number of workdays or work
hours required to complete a task.
• Effort does not normally equal duration.
• People doing the work should help create
estimates, and an expert should review them.
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INPUT
Tools & Techniques
OUTPUT
Expert Judgement
Duration Estimation
Project Management Plan
Analogous Estimating
Basis of Estimation
Enterprise Environmental Factors
Parametric Estimating
Projects Documents Updates
Organizational Process Assets
Three-point Estimation
Project Documents
Bottom-up estimation
Data Analysis
Decision Making
Meetings
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Analogous Estimating, is a form of
expert judgment and is also known as
Top-down Estimating. Analogous
estimates are typically less time
consuming and less costly than other
estimating techniques, but it’s also
less accurate.
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Parametric Estimating
•
Parametric estimate uses a statistical relationship
between historical data and other variables.
• More accurate than analogous estimate
• Example : A resource will take 20hrs per module and
hence 1000 modules will take 50hrs (50X20 = 1000hrs)
• Estimation is done by multiplying quantity of work by
labor hours per unit of work.
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• Three-point estimates, as you can probably
guess, use three estimates that when averaged
come up with a final estimate. The three estimates
you’ll use in this technique are the most likely estimate,
an optimistic estimate, and a pessimistic estimate.
•
Three-point estimates are needed for PERT estimates and Monte Carlo simulations
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• Program Evaluation and Review Technique (PERT) has the
following characteristics.
• It uses three estimates per activity - optimistic, pessimistic and most
likely
• It can be drawn only using AOA diagrams
• It can have dummy events
• PERT utilizes more information than CPM as it considers the
"Pessimistic" and "Optimistic" values in addition to the "Most Likely"
value in its calculations. The following are formula used by PERT Mean = (P + 4M + O)/6
Standard Deviation = (P-O)/6
Variance = ((P-O)/6)2
• GERT is another type of network diagram. It can support looping.
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Reserve time, also called buffers, time reserves, or
contingency reserve in the PMBOK Guide, means a
portion of time that is added to the activity to
account for schedule risk or uncertainty. You might
choose to add a percentage of time or a set number
of work periods to the activity or the overall
schedule.
For example, you know it will take 100 hours to run
new cable, you also know that sometimes you hit
problem areas when running the cable. To make
sure you don’t impact the project schedule, you build
in a reserve time of 10 percent of your original
estimate to account for the problems you might
encounter.
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• A buffer is additional time to complete a task.
• Murphy’s Law states that if something can go wrong,
it will.
• Parkinson’s Law states that work expands to fill the
time allowed.
• In traditional estimates, people often add a buffer to
each task and use the additional time whether it’s
needed or not.
• Critical chain scheduling removes buffers from
individual tasks and instead creates:
– A project buffer or additional time added before the
project’s due date.
– Feeding buffers or additional time added before tasks on
the critical path.
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You use the inputs and tools and techniques to
establish these estimates. Activity duration
estimates are an estimate of the required work
periods needed to complete the activity. This is a
quantitative measure usually expressed in hours,
weeks, days, or
months.
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• Uses results of the other time management
processes to determine the start and end dates
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.
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Schedule Management Plan
• A Guide to the PMBOK® notes that the schedule
management plan (a subsidiary of the project
management plan) is produced as part of the
Develop Project Management Plan process and
contains the criteria for formatting, developing, and
controlling the project schedule.
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Schedule Network Analysis
Schedule network analysis is a technique that
generates the project schedule. It employs a
schedule model and various analytical
techniques, such as critical path method, critical
chain method, what-if analysis, and resource
leveling to develop the schedule.
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Develop Schedule (Tools &
Techniques)
Critical path method (CPM) is a schedule network analysis
technique. It determines the amount of float, or schedule flexibility, for
each of the network paths by calculating the earliest start date, earliest
finish date, latest start date, and latest finish date for each activity.
The critical path (CP) is generally the longest full path on the project.
Any project activity with a float time that equals zero is considered a
critical path task.
Slack or float is the amount of time an activity can be delayed without
delaying a succeeding activity or the project finish date.
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• Activity-on-Node (AON):
– Uses nodes to represent the activity
– Uses arrows to represent precedence relationships
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Step 1-Define the Project: XYZ Products is bringing a new product on
line to be manufactured in their current facility in some existing
space. The owners have identified 11 activities and their precedence
relationships. Develop an AON for the project.
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• The longest path (ABDEGIJK) limits the
project’s duration (project cannot finish in
less time than its longest path)
• ABDEGIJK is the project’s critical path
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• The critical path does not necessarily contain all the
critical activities; it only accounts for time.
• 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.
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•
•
Floats are not the same as lead or lag.
Lead or lags are introduced (manually) to correct the
sequence while float is calculated in CPM.
• Float for all activities on critical path will be zero value.
•
A forward pass through the network diagram determines
the early start and finish dates.
• A backward pass determines the late start and finish
dates.
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ES
EF
LS
LF
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LS, LF Network
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Calculating Expected Task Times
optimistic  4most likely   pessimistic
Expected time 
6
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Estimating the Probability of
Completion Dates
• Using probabilistic time estimates offers the advantage of predicting
the probability of project completion dates
• We have already calculated the expected time for each activity by
making three time estimates
• Now we need to calculate the variance for each activity
• The variance of the beta probability distribution is:
po
σ 

 6 
2
2
– where p=pessimistic activity time estimate
o=optimistic activity time estimate
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Variances of Each Path
through the Network
Path
Number
1
Activities on Path
A,B,D,E,G,H,J,K
Path Variance
(weeks)
4.82
2
A,B,D,E,G,I,J,K
4.96
3
A,C,F,G,H,J,K
2.24
4
A,C,F,G,I,J,K
2.38
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Calculating the Probability of
Completing the Project in Less Than a
Specified Time
• When you know:
– The expected completion time
– Its variance
• You can calculate the probability of completing the project in
“X” weeks with the following formula:
specified time  path expected time  DT  EFP 
z


2
path standard time
σP 

Where DT = the specified completion date
EFPath = the expected completion time of the path
σPath 2  variance of path
Example: Calculating the probability of
finishing the project in 48 weeks
• Establish the z values to determine probabilities
• e.g. probability for path 1 is
Path
Number
Activities on
Path
Path Variance z-value
(weeks)
Probability of
Completion
1
A,B,D,E,G,H,J,K
4.82
1.5216
0.9357
2
A,B,D,E,G,I,J,K
4.96
1.4215
0.9222
3
A,C,F,G,H,J,K
2.24
16.5898
1.000
4
A,C,F,G,I,J,K
2.38
15.9847
1.000
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Float time is also called slack time and there are three types of float:
• Total Float – The amount of time an activity can be delayed without
delaying the planned project end date or milestone.
• Free Float – The amount of time an activity can be delayed without
delaying the early start date of successor activity or without
delaying the early start of any immediately following activities.
• Project Float – The amount of time a project can be delayed
without delaying an externally imposed project completion date
(other than calculated by CPM) by customer.
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Critical chain method is a schedule network
analysis technique that will modify the project
schedule by accounting for limited or
restricted resources. After the project
schedule network diagram is constructed
using duration estimates, dependencies, and
constraints, resource availability is entered
into the scheduling tool.
The modified schedule is calculated and you’ll
find that it often changes the critical path. The
new critical path showing the resource
restrictions is called the critical chain.
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Schedule compression is the method of shortening the
project schedule without changing the scope. Need for
compression occurs if a customer needs a date
prior to the end date shown in original schedule or to
bring back a project schedule back to baseline.
• Crashing – This approach adds more resources to activities
on the critical path to complete the project earlier. Crashing
almost always result in increased cost. Many options are
considered and the option with maximum compression with
minimum cost impact is selected.
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• Fast Tracking –Critical activities that
would normally be done in sequence
are allowed to be done in parallel or
with some overlap. Fast track may
result in rework and increases risk.
Communication requirements increases
during fast tracking.
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• What-If Scenario Analysis: In creating a
finalized, realistic schedule, ask what if a
particular thing changed on the project?
Would it shorten the schedule?
• Can calculate the effect of these changes through a Monte
Carlo Analysis – a method of estimating using computer
software to simulate the outcome of a project, making use
of three-point estimates for each activity and network
diagram.
• Can tell the probability of completing on a specific day,
with a specific amount of cost, overall project risk etc.
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• Allows one to level peaks and valleys of resource use
from one month to another, resulting in a more stable
number of resources used on the project.
• Produces a resource-limited schedule – may result in
lengthen the project, instead of hiring more resources.
• This method let’s schedule slip and cost increase in
order to deal with a limited amount of resources,
resource availability and other resource constraints.
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INPUT
Tools & Techniques
OUTPUT
Schedule Network Analysis
Schedule Baseline
Project Management Plan
Critical Path Method (CPM)
Project Schedule
Enterprise Environmental
Factors
Resource Estimation
Projects Documents Updates
Organizational Process Assets
Data Analysis
Schedule Data
Project Documents
Leads and Lags
Project Calendars
Agreements
Schedule Compression
Change Request
PMIS
Project Management Plan
Updates
Agile release planning
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The schedule can be displayed in a variety of ways:
• Project Schedule Network Diagram
• Gantt Charts/ Bar Charts
• Milestone Charts
The purpose of the Schedule Development process is to
determine the start and finish date for the each of the project
activity. The project schedule should be approved and
signed off by stakeholders and functional managers.
 This assures that they have read the schedule, understand the dates and
resource commitments, and will likely cooperate
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• 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.
• Symbols include:
– Black diamonds: Milestones
– Thick black bars: Summary tasks
– Lighter horizontal bars: Durations of tasks
– Arrows: Dependencies between tasks
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Summary Tasks
Duration of
Tasks
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• Many people like to focus on meeting milestones,
especially for large projects.
• Milestones emphasize important events or
accomplishments in projects.
• You typically create milestone by entering tasks that
have a zero duration, or you can mark any task as a
milestone.
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INPUT
Tools & Techniques
OUTPUT
Critical Path Method
Work Performance Info
Project Management Plan
PMIS
Schedule Forecasts
Working Performance Data
Resource Optimization
Change Requests
Organizational Process
Assets
Leads and Lags
Project Management Plan
Updates
Project Documents
Schedule Compression
Project Documents
Updates
Data Analysis
Control Schedule
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Schedule Control is concerned with:
1. Determining the current status of the
project schedule
2. Influencing the factors that create schedule
changes.
3. Determining that the project schedule has
changed, and
4. Managing the actual changes as they
occur.
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
Performance Reviews- Performance reviews
measure, compare, and analyze schedule performance
such as actual start and finish dates, percent complete,
and the remaining duration for the work in progress .

Variance Analysis- Variance analysis is a key factor
in monitoring and controlling project time because this
technique helps determine variances in schedule start and
end dates.
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• Software for facilitating communication helps
people exchange schedule-related information.
• Decision support models help analyze trade-offs
that can be made.
• Project management software can help in
various time management areas.
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The Schedule Control process has the following outputs:
1. Work Performance Measurements- Calculated Schedule
Variance (SV) and Schedule Performance Index (SPI) are
documented and communicated with Stakeholders.
2. Organizational process asset updates (lessons learned)
3. Change Requests – Approved schedule baselines shall be
only updated through integrative change control. SV & SPI
may result in change requests for baseline updates.
4. Project Management Plan Update
5. Project Document updates – Schedule data
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





Schedule Variance % indicates how much ahead or behind
schedule the project is in terms of percentage.
Schedule Variance % can be calculated as using the following
formula
SV % = Schedule Variance (SV) / Planned Value (PV) or
SV % = SV / BCWS
The formula mentioned above gives the variance in terms of
percentage which will indicate how much percentage of work
is yet to be completed as per schedule or how much
percentage of work has been completed over and above the
scheduled cost
Positive Variance % indicates % ahead of schedule.
Negative Variance % indicates % behind of schedule.
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• Perform reality checks on schedules.
• Allow for contingencies.
• Don’t plan for everyone to work at 100
percent capacity all the time.
• Hold progress meetings with stakeholders
and be clear and honest in communicating
schedule issues.
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