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Chapter 20Introduction to Systems Development and Systems Analysis
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall20-1
Learning Objectives
Explain the five phases of the systems development life cycle.
Discuss the people involved in systems development and the roles they play.
Explain the importance of systems development planning and describe planning techniques.
Discuss the various types of feasibility analysis and calculate economic feasibility.
Explain why system changes trigger behavioral reactions,What form this resistance to change takes, and how to avoid orminimize the resulting problems.
Discuss the key issues and steps in systems analysis.
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-2
Why Update Systems?
User or business changes
Technology changes
To improve business process
Create competitive advantage
Increase productivity gains
Integrate multiple systems
Aging systems need replacement
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-3
Software Development Problems
Most software development projects deliver less, cost more, and take longer than expected. Standish Group found that:
70 percent of software development projects were late 54 percent were over budget 66 percent were unsuccessful 30 percent were canceled before completion
American Management Systems found that: 75 percent of all large systems are not used Not used as intended, or Generate meaningless reports or inaccurate data
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-4
Systems Development Life Cycle (SDLC)
System Analysis
Conceptual Design
Physical Design
Implementation &
Conversion
Operations & Maintenance
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-5
SDLC Steps
System Analysis Information about system needs, costs, and so on are gathered.
Conceptual Design Gather system/user requirements.
Physical Design Concepts are translated into detailed specifications.
Implementation and Conversion New hardware and software are installed and tested. Employees are hired and trained or existing employees relocated. Processing procedures are tested and modified. Standards and controls for the new system are established and system
documentation completed.
Operation and Maintenance New system is periodically reviewed. Modifications are made as problems arise or as new needs become evident.
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-6
Systems Analysis Activities
Initial Investigation• What’
s the Problem
• What’s the Scope
Systems Survey• Gain
Understanding of Company
• Preliminary Assessment of Needs & Changes Required
• Develop Working Relationships
• Collect Data
Feasibility Study• Deter
mine Project Viability
Information needs and System Requirements• What do
Users Need
• Document System Requirements
Systems Analysis Report• Summ
arize and Document Activities
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-7
People Interacting in SDLC
Management
Accountants
Users
Information systems steering committee
Project development team
Systems analysts and programmers
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Planning SDLC
Project Development Plan Cost/benefit analysis Developmental and operational requirements (people,
hardware, software, and financial) Schedule of the activities required to develop and operate
the new application
Master Plan What the system will consist of How it will be developed Who will develop it How needed resources will be acquired Where the AIS is headed
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-9
Planning Technique—PERT Chart
Program Evaluation and Review Technique (PERT) Network of arrows and nodes representing project
activities that require an expenditure of time and resources and the completion and initiation of activities
Completion time estimates made Critical path—the path requiring the greatest amount of
time is determined
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-10
Planning Technique—GANTT Chart
A bar chart with project activities on the left-hand side and units of time across the top
Graphically shows the entire schedule for a large, complex project
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-11
Feasibility Analysis
Does it make sense to proceed with new system?
Economic: Will system benefits justify the time, money, and resources required to
implement it?
Technical: Can the system be developed and implemented using existing technology?
Legal: Does the system comply with all applicable federal and state laws,
administrative agency regulations, and contractual obligations?
Scheduling Can the system be developed and implemented in the time allotted?
Operational Does the organization have access to people who can design, implement, and
operate the proposed system? Will people use the system?
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-12
Capital Budgeting: Economic Feasibility
Cost-Benefit Analysis
Benefits and costs are estimated and compared to determine whether the system is cost beneficial.
Benefits and costs that are not easily quantifiable are estimated and included.
If they cannot be accurately estimated, they are listed, and their likelihood and expected impact on the organization evaluated.
Techniques Payback Period
Number of years required for the net savings to equal the initial cost of the investment.
Net Present Value (NPV) Future benefits are discounted
back to the present. Initial cost is subtracted. Positive NPV = economically
feasible.
Internal Rate of Return (IRR) The effective interest rate that
results in an NPV of zero. A project’s IRR is compared with
a minimum acceptable rate to determine acceptance or rejection.
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-13
System Failure Due to Change
The best system will fail without the support of the people it serves.
Why people resist change: Fear Lack of top management support Lack of communication Disruptive nature of change Methods of instituting change Biases and emotions Personal characteristics and background
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Types of Resistance
Aggression Behavior that destroys, cripples, or weakens system
effectiveness, such as increased error rates, disruptions, or deliberate sabotage
Projection Blaming the new system for everything that goes wrong
Avoidance Ignoring a new AIS in the hope that the problem (the
system) will eventually go away
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-15
Preventing Resistance
Obtain management support
Meet user needs
Involve users
Stress new opportunities
Avoid being too emotional
Provide user training
Reexamine performance evaluation to make sure they are aligned with new system
Keep communication lines open
Control users expectations
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall 20-16
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