Task Analysis and Work Breakdown Structure

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Once we have completed our plan on what to deliver
and the contents of deliverables (via requirements),
we need to:
plan out how to accomplish the deliverables
Task Analysis is Part of Planning
Task Analysis
• Task analysis is domain dependent– thus you
need domain experts to help: (if you want to do well)
–
–
–
–
–
build a desk
plant a tree
write computer program
build a road
make a spaghetti dinner
• Software project task analysis is no different
– you need domain knowledge to do this well
•
•
•
•
computer science
software engineering
information technology
math/science/arts
task analysis: – the definition and sequencing of tasks needed to accomplish the result.
From the Requirements to Work Breakdown
Structure (WBS)
• We get 2 main sets of information from Requirements:
– 1) list of deliverables to the customers
– 2) descriptions (functional & non-functional) about those deliverables
Note: date or schedule requirement is purposely not included, yet
• The first “high level” task of sequencing the required customer
deliverables may seem simple, but --- consider the example list:
–
–
–
–
code
user guide
support plan
development process document
WBS: is the listing and sequencing of the work activities needed to produce
the required deliverables. (Note that there may be concurrent activities.)
Assume these external deliverables
code
user guide
product
support
plan
How are these related ?
dev.
process
doc.
A ‘Sample’ Sequence of External Deliverables
code
dev.
process
doc
product
support
plan
user guide
End
- Do you all agree ? Discuss - what do you need to decide here.
- Also decide if the sequence of deliverables “equal” sequence of
activities (tasks) to produce the material
Representing in “Schedule” form
Deliverables
became
Tasks !
Note: added new parameter
Tasks Resp.
Proc.
doc
Gw
Code
Gx
User
Guide Gy
S.Plan Gz
month1
month2
month3
All the same length
and no overlap
Effort Analysis
• Estimation of “Effort” for each deliverable
– need to understand the subtasks required to
produce the deliverable and any “intermediate
deliverables” that may be required.
– need to break it (deliverable or task) down more
• by sub-components
• to the level where :
How important are these?
– one person can do the task
– skill & productivity of the person can be described
– actual task can be described and size estimate has some
comparable “past history” or “algorithm”
A Deeper Work Breakdown Structure (WBS)
of “Developing” Product Support Plan
Interview
Customer
for
input
Analysis
and
Develop
Outline
Not
O.K.
1 cycle
only
O.K.
Review with
Customer
Develop
the whole
Support Plan
Final Review
End
Effort Analysis & A Deeper Work Breakdown
Structure (WBS)
of “Developing” Support Plan
Interview
Customer
for
input
**
Analysis
and
Develop an
Outline
Effort is Based on the assumptions:
1. How much (size of) work is
estimated.
2. Productivity of the assigned person
2 p-days
**
1/2 p-day
O.K.
1/2 p-day
Review with
Customer
Develop
the whole
Plan
5 p-days
** - Do not forget about wait time
- how many people are required ?
- what kind of skill & background ?
1/2 p-day
1 p-day Final Review
End
2 Major “Information/Assumption” Needs for
Effort Analysis & Deeper WBS &Schedule
• An estimate of the “size” of the work:
–
–
–
–
pages of document
lines of code
number of people to visit
length of meeting
• Productivity of the “individual” assigned
–
–
–
–
5 pages a day (for document)
30 loc/day (for source code)
2 people/hour (for interview or visits)
3hrs/meeting (for meetings)
Assuming WBS is Performed for Each
Deliverable
code
develop.
Process
doc
P-25 days
Support
plan
P-7 days
P-10 days
End
user guide
P-10 days
Assume you agree with the sequence
For each of the major deliverables, estimate the required effort in “p-days” via WBS
(*** these are person-days ---- want to get to individuals)
Improving on Task “Schedule”
Having chosen specific resources
Tasks Resp.
Proc
Qais
Code
Justin
User Gabe
Guide
S.Plan Marshon
May
June
July
Overlapping, different length
Adding Milestones in “Schedule”
Tasks Resp.
Proc
Qais
Code
Justin
May
June
July
User
Gabe
Guide
S.Plan Marshon
Minor
Minor Major Major (project end)
General flow of WBS to Timeline Schedule
Identify the
deliverables
For each task:
compute the effort/timeline
for that task by dividing
sise by productivity
After all the timelines
for all the tasks for all
the deliverables are
computed do following
step
For each deliverable:
identify the tasks for
completing the deliverable
For each task:
-Estimate the productivity
of the assigned resource
for effort analysis
Sequence the tasks
For each task:
-Estimate the size
for effort analysis
Lay out the timeline for all
the ordered tasks needed for
each of the deliverables.
(task timeline may overlap)
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