1. Project Management for Software Engineers (Summer 2017)
LECTURES 7, 8, 9
Project Scheduling &
Resource Allocation
July 7-11, 2017
(9:00 am – 11:40 pm PST)
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

2. Logistics Homework #2 is assigned & due on 07/14/17
Mid-Term Exam will be on 07/11/17
Projects:
Planning Reports are due on 07/12/2017, guidelines provided
50% progress presentation on 07/14/2016
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

3. Concurrent with budget
How to manage Time?
Plan Schedule Management
Define Activities
Sequence Activities
Estimate Resources
Estimate Durations
Develop Schedule
Control Schedule
Concurrent with budget
Estimation
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

4. Schedule Management Plan
Project Schedule Model Development
Level of Details & Accuracy
Units of measurement
Organizational Procedures Links
Project Schedule Model Maintenance
Control Thresholds
Rules of Performance Measurement
Reporting Formats
Process Descriptions
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

5. Define Activities
Breakdown work packages into tasks / Milestones / Events
Right level of details
Details can vary in place and time (Rolling Wave)
Should be able to assign resources
Don’t forget PROCUREMENT activities!
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

6. Estimate Resources
Resources: A fleet of resources has certain productivity (Work Unit / Hour), which is estimated based on management experience, corporate knowledge base, or industry standards
More resources could be used to reduce duration, but from certain point on, additional resources deteriorate productivity (management overhead)
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

7. Estimating Activity Duration
Estimate based on Resources
Static: Fixed Duration
Dynamic: Resource Driven
Estimate based on past experience:
Deterministic: Assign ONE reasonable duration based on experience
Statistical (PERT): A derivation of Beta distribution (a, b)
Optimistic duration (Min of 100 samples)= a
Pessimistic duration (Max of 100 samples) = b
Most likely duration (mode) = m
PERT (a, m, b) = Beta(alpha,beta) * (b - a) + a
Relations between parameters:
Why Beta: because we could have special cases: a=m, b=m, m-a=b-m, etc. which is true for duration estimates as well
Example: Page
TE (m) = (a+4m+b)/6
s = (b-a)/6
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

8. Sequence Activities Hard logic (Necessity) or Soft logic (Preference)
Type of Relationship
Constraints (MSP)
Network Presentations:
Coding
Debugging
Develop UI for iOS
Develop UI for Android FS SS FF SF
ASAP
SNET
ALAP
SNLT
FNET
FNLT   
MFO
MSO  *
Also discuss lag & lead, especially for software development *
AON
AOA
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

9. Building the Schedule
Once we define all activities, their durations, and then sequence them, we notice:
Some activities can have limited delay without impacting any other activities (Free Float)
Some Activities can have limited delay without impacting the project completion date, while delaying some other activities (Total Float)
Certain activities cannot have any delay. If they are delayed, a series of subsequent activities AND the project completion date will be delayed (ZERO Float)
ZERO FLOAT activities are called “CRITICAL” activities and the sequence(s) of critical activities is (are) called “CRITICAL PATH”
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

10. Finding the Critical Path(s)  C.P.M.
FORWARD PASS
ES = Max(EFp‘s)
EF = ES + DUR
ES(End)
EF(End)
LF(End)
LS(End)
+Dur
-Dur
EFp1
EFp2
EFp3
LSs1
LSs2
LSs3
LS = LF - DUR
LF = Min(LSs‘s)
BACKWARD PASS
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

11. Important Definitions*
Network analysis: The process of identifying early and late dates for the uncompleted portions of project activities.
Logic: The collection of activity dependencies that make up a project network diagram
Early Start (ES): The earliest time an activity can start, based on the network logic and/or any schedule constraints
Early Finish (EF): The earliest time an activity can finish, based on the network logic and/or any schedule constraints
Late Start (LS): the latest time an activity can start without delaying any milestones (e.g. project completion)
Late Finish (LF): the latest time an activity can finish without delaying any milestones (e.g. project completion) *
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

12. Exercise: Calculate the Critical Path
Note: Depending on how you setup your calendar, you may need to subtract a day in the TF&FF calculations (Not a concern in this class)
HOW TO READ THE FORMULAS:
Total Float of one activity is Late Finish – Early Finish of that activity
Free Float of an activity is Minimum of Early Starts of its successors – Early Finish of that activity
Note: Always FF<=TF
On the“CRITICAL PATH” : ES=LS & EF=LF
TOTAL FLOAT = LF-EF
FREE FLOAT = Min(ESS)-EF
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9/18/2018

13. Resource Allocation
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14. Resources define Cost & Duration
You learned how to estimate activities cost (C) and duration (T) based on resources (R) cost and productivity
Which equation is correct?
T=f(R,C) OR C=f(R,T) OR R = f(C,T)
Which one’s are the independent variables?
which ones are the dependent variables?
There is no independent variables is these equations!
While planning the project, we constantly evaluate our options to find the scenario that we feel optimizes project needs
The decision is based on our experience, project requirements, company limitation, and other constraints
If we have hick-ups during execution, we can change our strategy to compensate for our loses on one on the variable (T,C,R)
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

15. How to compensate for delays?
Activities can be accelerated by spending more money, assuming additional resources can be made available
The entire schedule will be impacted:
Critical path could change (or a new one may be added)
All participants will be impacted (suppliers, subcontractors)
The project uncertainties (risks) increase
The metric to find the most effective crashing options:
Lower slope means “bigger bang for the buck”!
How to prioritize? Sort activities by?
Sort activities by: 1. TF, 2. Slope 3. ES
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

16. Resource Loading / Leveling
Resource loading describes the amount of resources an existing schedule requires, gives an understanding of the demands a project will make of a firm’s resources
Resource leveling optimizes & levels use of resources by moving activities within their float (if time is constrained) or beyond their float times, extending schedule constraints (if resource availability is constrained)
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

17. Resource Leveling Example (Career Day)
Resource-loaded baseline schedule (Red=over-allocation)
Resource Leveling within available floats, beyond available resources
Resource Leveling within available resources, beyond available floats
Manual leveling to minimize resource allocation gaps
Graduate Assistant Effort
Completion Date
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018

18. Example Project Source: Project Profiler website
University of Southern California, IMSC/SSU CERTIFICATION PROGRAM
9/18/2018