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C H A P T E R
Systems
Investigation
and Analysis
Systems Development
• What is it?
“If you can’t do it better,
why do it?”
-Herbert H. Dow,
Founder, Dow Chemical Company
Why Plan?
• Why do we need a process?

2
Why Plan?
• For every 100 application development
projects, there are 94 restarts.
• 60% of companies rated themselves
successful at meeting the data analysis
expectations of end users and senior
management. What about the other 40%?
• 73% of IS software projects have been
cancelled, over-budget, or late.
Participants in Systems
Development
Stakeholders
Individuals who are
beneficiaries of the systems
development effort.
Users
Individuals who
interact with the
system regularly.
Systems Analyst
Professional who
specializes in analyzing
and designing business
systems.
Programmer
Individual
responsible for
modifying or
developing
programs to
satisfy user
requirements.
Who manages the process?

3
What’s a Systems Analyst
• Computer Systems Analysts
• California Occupational Guide Number 541
• “The first task of the Computer Systems Analyst is the evaluation of
business procedures and problems. Analysts begin an assignment by
talking with managers or specialists to determine the precise nature
of the problem and to break it down into its component parts. This
may involve interviews with staff to specifically identify what
information is being processed, where it comes from, and where it
goes. In addition to the interview method of data collection, analysts
also conduct written surveys and observe workers performing tasks.
On occasion an Analyst may assume the worker's role for a week or
so in order to understand and document the processes being
performed.”
• After sufficient information has been collected, the analyst
prepares charts and diagrams that constitute a representation of
the new system in terms which managers or non-data-
processing personnel can understand. Analysts consult
with management throughout this phase in order to
confirm that the analyst and the management agree on the
principles of the system. Analysts also prepare analyses
which present cost versus benefit as a result of implementing
the proposed new system.
• Once the system is accepted, Systems Analysts prepare
specifications for programmers to follow. The specifications
include detailed descriptions of the records, files, and documents
used in processing, and data flow charts describing the
interrelationship of the data elements to be considered by
the programmers. The analysts also coordinate the
development of test problems to debug the system and
participate in trial runs of the systems. They also may
determine what computer hardware and software will be needed
to set up the system.

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• Employers usually want analysts with a background in accounting,
business management, or economics for work in a business
environment
• A growing number of employers seek applicants who have a degree
in computer science, information science, information systems, or
data processing. Regardless of college major, employers look for
people who are familiar with programming languages. Courses in
computer concepts, systems analysis, and data base management
systems offer good preparation for a job in this field. Systems
Analysts must be able to think logically and should like working with
ideas. They often deal with a number of tasks simultaneously. The
ability to concentrate and pay close attention to detailalso is
important.
Typical Reasons to Initiate a Systems
Development Project?
Systems Development
Life Cycle
• Systems Investigation (Problem)
§ What is the problem and is it worth solving?
• Systems Analysis (Solution)
§ What can the IS do to solve the problem?
• Systems Design (Plan)
§ How will the IS do what it must to solve the problem?
• Systems Implementation (Action)
§ Creating, acquiring, assembling, and implementing
• Systems Maintenance & Review
§ Ensure operations and make necessary modifications

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Systems Development
Life Cycles
Rapid Application
Development (RAD)
A concept that products can be developed
faster and of higher quality through:
§ Gathering requirements using workshops or focus
groups
§ Prototyping and early, reiterative user testing of
designs
§ The re-use of software components
§ A rigidly paced schedule that defers design
improvements to the next product version
§ Less formality in reviews and other team
communication
Managing Change
• Recognize Potential Concerns
§ Jobs will be lost
§ More work will be created
§ Developers don’t understand processes
§ Other problems are more pressing
§ Unwillingness to learn new procedures

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Project Management
• Use of project management tools
§ Schedules – What is to be done
§ Milestones – Critical dates for completion
§ Deadline – When the project is to be operational
§ Critical path – Activities with zero slack
§ Program Evaluation Review Technique (PERT)
§ Gantt chart
PERT Chart
(Program Evaluation and Review Technique)
• A project management tool used to
schedule, organize, and coordinate tasks
within a project.
§ Developed by the U.S. Navy in the 1950s to
manage the Polaris submarine missile program.
• A similar methodology, the Critical Path
Method (CPM) was developed for project
management in the private sector at about
the same time
§ Has become synonymous with PERT
PERT Chart

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Use of Computer-Aided Software
Engineering (CASE) Tools
• Computer-Aided Software Engineering (CASE)
§ Tools that automate many of the tasks required in a
system development effort and enforces adherence
to the SDLC.
• Upper CASE Tools
§ Tools that focus on systems investigation, analysis, and
design activities
• Lower CASE Tools
§ Tools that focus on the later implementation stage of systems
development. May be capable of automating code creation.
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Systems Investigation
• Answers the following questions…
§ What problems might a new or enhanced
system solve?
§ What opportunities might be provided?
§ What are the associated risks?
§ Is it feasible…?
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Feasibility Analysis
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hTechnical Feasibility
§ Can the hardware, software, and other system components
be acquired or developed to solve the problem?
hOperational Feasibility
§ Can the project be put into action or operation?
hSchedule Feasibility
§ Can the project be completed in a reasonable
amount of time?
hEconomic Feasibility
§ Does the project make financial sense? (NPV)
Systems Analysis
Systems Analysis
Data Collection
• Learn more about the problems identified
in the current system.
§ How?
33

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Systems Analysis
Data Analysis
• Manipulating the collected data so that
it is usable for the development team
members who are participating in
systems analysis.
• Can be generated with CASE tools
§ Entity Relationship (ER) Diagrams
§ Data Flow Diagrams (DFD)
§ Application Flowcharts
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Systems Analysis
Requirements Analysis
• Requirements Analysis
§ An assessment used to determine user,
stakeholder, and organizational needs in a
new system (functional requirements).
u What they want and expect
u What is critical to the business (CSF)
u How they wish to interface (screen layouts)
u What output they need (report layouts)
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