Information Systems
Project Management
IS Project Estimation
Miguel Nunes
email: j.m.nunes@sheffield.ac.uk
Aims of this Session
• To introduce estimation as an important project
management activity;
• To discuss different types of estimation methods;
• To discuss different stages of the estimation
process.
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Information System
Definition
An Information System can be defined technically as a set
of interrelated components that collect, process, store
and retrieve, and distribute information to support
decision making, co-ordination and control in an
organisation.
An information system is an organisational and
management solution, based on information and
communication technology, to a challenge posed by the
environment.
Information System
Definition
A system that assembles, stores, processes and delivers
information relevant to an organisation (or socio-technical
environment), in such a way that the information is
accessible and useful to those who wish to use it as
required by their activity practices, including managers,
staff, customers, suppliers, other business partners and
citizens.
An IS is therefore an human-activity system which may or
may not involve the use of IT based systems.
Types of IS
Project Resources
Any IS project has at least 4 stages:
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start-up;
development;
completion;
operational.
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Types of IS Project
Resources
A resource is any item or person required for the execution
of the project (from clips to key technical personnel).
In general resources can be categorised as follows:
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Labour (also known as Human Resources);
Equipment;
Materials;
Space;
Services;
Time;
Budgetary resources.
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Types of IS Project
Resources
These team members may take one or more of the following
types of roles:
 Support:
 Management:
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 Technical:
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Project Manager;
Quality Manager;
Risk Manager;
Configuration and
Integration Manager;
Analysts and Designers;
Programmers;
Graphics Designer;
Database Administrator;
Implementation Officer;
Users;
Testers;
Project Champion;
Secretaries;
Clerks;
Training Officer:
 Organising:
And more ……….
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Steering Committee;
User Group;
Risk Management
Committee;
Joint Application
Development Team.
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Types of IS Project
Resources
Human Resources is very expensive (typically 80%
of budget of the project) and the more specialised
the resources are the more scarce and expensive
they become.
Human resource allocation depends on:
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Management Style of Project Manager.
Type and nature of the project;
IS Methodology Selected;
Constraints and Budget of the Project.
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Types of IS Project
Resources
Time is a resource that is very scarce
and limits the use of other resources.
Time allocation in the plan depends on
IS methodology, effort estimation,
quality standards used, risk
management and the use of human
resources.
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IS Development
Methodologies
“ a coherent collection of concepts, beliefs, values and
principles supported by resources to help a problemsolving group to perceive, generate, assess and carryout in a non-random way changes to the information
system”
(Avison and Wood-Harper, 1990)
1. Set of methods for tackling the different problems involved.
2. Sound theoretical basis in order to understand why and when to
use the methods.
IS Development
Methodologies
A collection of procedures, techniques, tools and
documentation aids that help developers in their efforts to
understand users, their socio-technical environment, their
work practices and their information needs.
IS Methodologies consist of phases whish will guide the
systems developers in what to do and their choice of
techniques that might be appropriate at each stage. Each
phase may contain subphases.
These phases (or stages, or main activities) form the IS
Project and help manage, control and evaluate the project.
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IS Development
Methodologies
There are 3 main types of methodologies in use
today:
 Structured Approaches (e.g. SSDAM)
 Agile Methodologies

Prototyping approaches (e.g. RAD or DSDM)

Incremental approaches (e.g. XP or SCRUM)
 Object Oriented Approaches (e.g. UML)
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Information Systems
Project Planning
Time allocation in the plan depends on the IS methodology selected,
effort estimation, quality standards used, risk management and the use
of human resources.
Question answered:
 What IS Methodology to use?
 Who will do the work?
Questions remaining:
 When will the work be done?
 How long will each of the stages, activities and tasks
last?
 What type of quality do we need for our work and
product?
 What risks are we willing to run?
Information Systems
Project Estimation
Estimation implies that targets are set and that the project
manager tries to meet those targets by allocating people
and resources to tasks and activities and trying to
anticipate how long each task my take to successfully
achieve each of the targets.
Information Systems
Project Planning
“It is very easy for estimators to be overly
optimistic. At the beggining of a project, it is natural
to assume that everything will work as planned.
But, because the need to accomplish a wide
variety of tasks – and their realtionships – projects
rarely proceed as sheduled.”
Why ?
Information Systems
Project Estimation
Estimation is very difficult for IS project estimations
because:
• IS projects are usually one-off affairs;
• IS estimates are usually prepared before a detailed
specification of requirements is available (usually only
after design stage, e.g. after TSO in SSADM);
• Programmers are often bad estimators, managers are
often not technical enough in their thinking;
• Professionals in a team often have very different
degrees of experience (what works for one may not work
for others …);
• Very fast changing technologies make it sometimes
difficult to use previous experience.
Estimates, but how?
Estimates can be obtained by two means:
• Experience and Analogy;
• Mathematical formulae.
Experience and Analogy tend to be the more
important since it is able to draw upon the
“real world events” in making predictions for
the future.
Mathematical formulae are used to quantify and
manipulate past experience.
Estimating and
Experience
Estimating
( When and Who
according to
What and How)

Planning
Experience …. ,
experience … ,
experience.
Experience ... ?
Traditionally, projects have been estimated by
intuitive methods based on an individual’s
previous “experience” often
 guesswork
 “guesstimate” multiplied by some “factor” to
account for the unexpected.
Mathematical
Approaches
Lines of Codes (LOC);
Function Points (FP);
Object Points (OP).
but can we use these ???
Usually garbage in gabage out processes
based on guesstimate input.
Estimating
Estimation must take account of broader project,
organisational, economic and business
considerations (holistic view).
The accuracy of an estimate depends on:
•
•
•
•
the quality of the data used to obtain it;
the quality of the information available;
the expertise of the estimator
... and a reasonable time scale to calculate the
estimate.
Estimating ...
But how then?
The natural human problem
solving method is to
subdivide a problem until it
is small enough to be
understandable and
manageable, and then hope
to combine the solutions to
answer the original
problem.
Process-Based
Estimation
Process decomposition sets of:
Stages into activities
Activities into tasks.
Consideration of past experience and data from past projects
through:
 expert judgement; or
 analogy.
Consideration of “especial factors” (individual skill, support
tools, communication and co-ordination problems);
Estimation of effort required for each individual task.
Process-Based
Estimation
Usually a top-down approach:
 Starting from an understanding of the whole project
and then broken down into the component stages,
activities and task.
Why ?
That is
why.
Process-Based
Estimation
But … the final project estimate is calculated
bottom-up:
Once component tasks are identified, understood
and sized these individual tasks are identified and
aggregated to determine activity estimates,
which in turn are aggregated to determine
stage estimate,
which in turn are aggregated to
determine an estimate for the whole project.
Process-Based
Estimation
Detailed Task Lists (DTL)
A detailed task list (DTL) is a listing of
unique work packages (tasks, activities and
stages) drawn form applying a particular IS
methdology to a specific project, including
clear description of:
- Work to be done;
- Assignment of responsibilities;
- Predecessor relationships.
Process-Based
Estimation
Work Breakdown Structure (WBS)
The Work Breakdown Structure (WBS) are top-down
herarchical charts of phases, activities, tasks and sub-tasks
required to complete the project.
These charts are build from the DTLs by adopting the 4 basic
stages of an IS project: start-up; development; completion and
operational.
Therefore, the elements of a WBS are discrete work packages
that can be separately estimated, planned and budgeted
(Cantor, 1998).
Process-Based
Estimation
WBS example
Process-Based
Estimation
WBS representation?
Hierarchical trees ...
An then use in ...
• CPM diagrams;
• Gantt charts.
Process-Based
Estimation
So will we be secure with
process based estimation?
“It is very easy for estimators to be overly
optimistic. At the beggining of a project, it is natural
to assume that everything wll work as planned.
But because the need to accomplish a wide variety
of tasks – and their realtionships – projects rarely
proceed as sheduled.”
Still? ... Why ?
Ahh …
but this is a
bit boring ….
This module’s question:
“We know why projects fail,
we know how to prevent their
failure -- so why do they still
fail?“ Cobb (1995)
Old question!???
Project Management
What has happened ?
What is happening ?
What is going to happen ?
What needs to be done ?
How are we going to do it ?
When are we doing it ?
Who is going to do it ?
What is the quality of our work (product) ?
What are the risks involved ?
Project
Management
Planning and Organising
(What and How)
Estimating
( When and Who)
Scheduling and Monitoring
( awareness of progression, remediation
action, quality assurance)
Planning and
Organising
Planning and Organising
(What and How)
Understanding requirements;
Selecting a methodology;
Estimating Effort;
Determining deliverables and milestones;
Determining verification and validation
checks.
To Sum up ...
Allocation of time and human resources should be is based
on Process Based Estimation ... supported by DTL and
WBS and expressed in terms of Gantt and CPM charts.
However, estimation is an
ongoing activity that starts
at the initial proposal
stage and continues
throughout the lifetime of
a project and requires
good communication in
the team.
It is not THE whole
answer to our
question.
To Sum up ...
If Time allocation in the
plan depends on IS
methodology, effort
estimation, quality
standards used, risk
management and the use
of human resources.
Then we still have two
questions to answer.
To Sum up ...
Your Turn now !!!!
Group 1 - UML
Group 2 - XP
For Tomorrow:
Group 3 - RAD
Group 4 - SSADM
Prepare the structure of your project by identifying
ALL the phases, activities and tasks of that your
methodology needs for the specific IS Project in the
case study and express it in terms of a DTL, a WBS
and a Gant Chart.