Chapter 15 Systems Development. 2 Learning Objectives When you finish this chapter, you will Understand the systems development life cycle. Be able.

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Management Information Systems, Second EditionEffy Oz

Chapter 15Chapter 15Systems DevelopmentSystems Development

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Learning ObjectivesLearning Objectives

When you finish this chapter, you will

Understand the systems development life cycle.

Be able to list and explain the pros and cons of prototyping.

Understand how software tools facilitate the monitoring and controlling of systems development.

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Learning ObjectivesLearning Objectives

Recognize the difficulties involved in systems development.

Be able to list the advantages and disadvantages of different system conversion strategies.

Understand the concept of systems integration.

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Why Develop an IS?Why Develop an IS?

Three phenomenon that trigger IS development

An opportunity (proactive)

A problem (reactive)

A directive

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The Systems Development The Systems Development Life Cycle (SLDC)Life Cycle (SLDC)

Figure 15.1 The systems development life cycle

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Analysis

Determines what need the system will satisfy

Investigation Developers interview managers and perspective

users to determine business needs.

Three feasibility studies performed.

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Figure 15.2 Phases in systems analysis

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The Technical Feasibility Study Ensures hardware and software exist to build

the system

The Economic Feasibility Study Benefits of the system weighed against the cost

The Operational Feasibility Study Determines if system will be used as intended

Requirements Definition Specific requirements of system defined

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Figure 15.3 Estimated benefits and costs of an IS ($)

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Figure 15.4 Phases in systems design

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Design

Logical Design Translation of user requirements into detailed

functions of the system

Physical Design

Construction

Systems Testing

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Figure 15.5 Payroll system development. Using the divide-and-conquer approach, the planned system is broken into hierarchical modules.

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Figure 15.6 A flowchart describing a sales bonus system

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Figure 15.7 Data flow diagram symbols

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Figure 15.8 The sales bonus system: a data flow diagram

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Figure 15.9 Activities in systems implementation

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Implementation

Training

Conversion Parallel Conversion Phased Conversion Cold Turkey Conversion Pilot Conversion

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Figure 15.10 Strategies used to convert from one IS to another

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19Figure 15.11 Activities in systems support


Support

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PrototypingPrototyping

Systems developed using an iterative rather than a systematic process

Purpose is to develop a working model as quickly as possible, which can be tweaked and revised

Significantly shortens systems development backlog

Can increase risk of incompatibility and other unforeseen mishaps

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Figure 15.12 In prototyping, refinement of the system continues until users are satisfied.

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Figure 15.13 When to prototype and when not to prototype

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Computer-AidedComputer-AidedSoftware EngineeringSoftware Engineering

Computer-Aided Software Engineering (CASE tools)

System development programs that ease and speed design and construction of new ISs

Application generators

I-CASE tools

Rapid Application Development (RAD)

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Project ManagementProject ManagementProject Management Tools

Project Evaluation and Review Technique (PERT) PERT chart shows events, required activities, and

relationships Advantage: Communication of interdependencies

among activities

Gantt Chart Represents activities and start and completion times,

but not the relationships among activities Advantage: Simple and linear

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Project ManagementProject Management

Figure 15.14a Project management software allows managers to use both PERT charts (above) and Gantt charts (Figure 15.14b) to control projects.

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Figure 15.14b Gantt chart

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Figure 15.15 Dimensions of project management

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Project Management Goals

Complete the project on time.

Complete the project within budget.

Meet requirements.

Meet expectations.

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Figure 15.16 IS development projects: challenges and failures

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Project Management Functions

Communication Management

Schedule Management

Quality Management

Financial Management

Resource Management

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Systems DevelopmentSystems DevelopmentLed by End UsersLed by End Users

JAD: An example of User-led Systems Development

Joint Application Development (JAD): method to be used in SDLU

Uses six-step process to take the team through planning and design

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Systems DevelopmentSystems DevelopmentLed by End UsersLed by End Users

Figure 15.17 The six steps of JAD

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Systems DevelopmentSystems DevelopmentLed by End Users Led by End Users

JAD Critical Success Factors

All participants must be committed to JAD process. Customers and IS people must agree on project’s scope. Sponsor must be supportive and involved. Team members must be empowered decision makers. Business objectives must be clearly defined. Business process must be understood. Team members must be able to meet two or more days

per week. Members must be committed to the team.

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Systems IntegrationSystems Integration

Takes a look at the information needs of an entire organization (or a major division)

Analysts integrate existing systems so that:

Data can flow more easily among business units.

Users can access different types of data via a single interface.

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Ethical and Societal IssuesEthical and Societal IssuesShould IS Professionals Be Certified?Should IS Professionals Be Certified?

Malfunctioning ISs

Faulty systems may wreak havoc, causing financial damage or even death

Should IS professionals be certified based on the high investment and risk involved in their work?

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Ethical and Societal IssuesEthical and Societal IssuesShould IS Professionals Be Certified?Should IS Professionals Be Certified?

Certification Pros

Protect potential employers Protect clients of consultants Fewer software-related failures

Certification Cons

Difficult to measure software competence May create a “closed shop:” decreased

competition, decreased incentive to improve skills

Chapter 15 Systems Development. 2 Learning Objectives When you finish this chapter, you will Understand the systems development life cycle. Be able.

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