© 2007 by Prentice Hall Management Information Systems, 10/e Raymond McLeod and George Schell 1 Management Information Systems, 10/e Raymond McLeod and George Schell

© 2007 by Prentice Hall Management Information Systems, 10/e Raymond McLeod and George Schell 2 Chapter 7 Systems Development

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 3 Learning Objectives ► Recognize the systems approach as the basic framework for solving problems of all kinds. ► Know how to apply the systems approach to solving systems problems. ► Understand that the systems development life cycle (SDLC) is a methodology – a recommended way to develop systems.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 4 Learning Objectives (Cont’d) ► Be familiar with the main SDLC approaches – the traditional waterfall cycle, prototyping, rapid application development, phased development, and business process redesign. ► Know the basics of modeling processes with data flow diagrams and use cases. ► Understand how systems development projects are managed in a top-down fashion. ► Be familiar with the basic processes of estimating project cost.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 5 The Systems Approach ► John Dewey identified three series of judgments involved in adequately resolving a controversy 1. Recognize the controversy 2. Weigh alternative claims 3. Form a judgment ► During the late 1960s/early 1970s, interest in systematic problem solving strengthened ► Systems approach — a series of problem-solving steps that ensure the problem is first understood, alternative solutions are considered, and the selected solution works.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 6 Series of Steps ► Preparation effort prepares the problem solver by providing a systems orientation.  Business areas, level of management, resource flows ► Definition effort consists of identifying the problem to be solved & then understanding it. ► Solution effort involves identifying alternative solutions, evaluating them, selecting the one that appears best, implementing that solution, & following up to ensure that the problem is solved.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 7 Figure 7.1 Phases & Steps of Systems Approach

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 8 Figure 7.2 Each Business Area is a System

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 9 Definition Effort Terminology ► Problem trigger is a signal that things are going better or worse than planned. ► Symptom is a condition that is produced by the problem & is usually more obivious than the root cause of the problem. ► Problem is a condition or event that is harmful or potentially or beneficial or potentially beneficial to the firm.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 10 Figure 7.3 Analyze System Parts in Sequence

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 11 Select the Best Solution ► Analysis – a systematic evaluation of options. ► Judgment – the mental process of a single manager. ► Bargaining – negotiations between several managers.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 12 Systems Development Lifecycle ► Methodology is a recommended way of doing something. ► Systems development lifecycle (SDLC) is an application of the systems approach to the development of an information system. ► Traditional SDLC stages are:  Planning  Analysis  Design  Implementation  Use.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 13 Figure 7.4 Circular Pattern of the System Life Cycle

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 14 Prototyping ► Prototype is a version of a potential system that provides the developers & future users with an idea of how the system in its completed form will function. ► Prototyping is the process of producing a prototype. ► Best suited for small systems – reflecting the prototyping influence.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 15 Evolutionary Prototype ► Evolutionary prototype is continually refined until it contains all of the functionality that users require of the new system. The steps involved are:  Identify user needs.  Develop prototype. ► Integrated application developer ► Prototyping toolkit  Determine if the prototype is acceptable.  Use the prototype.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 16 Figure 7.5 Development of Evolutionary Prototype

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 17 Requirements Prototype ► Requirements prototype is developed as a way to define the functional requirements of the new system when users are unable to articulate exactly what they want. Begin with the Evolutionary Prototype steps, then the next steps are:  Code the new system;  Test the new system;  Determine if the new system is acceptable;  Put the new system into production.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 18 Figure 7.6 Development of Requirements Prototype

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 19 Attraction of Prototyping ► Communications between the developer & user are improved. ► The developer can do a better job of determining the users’ needs. ► The user plays a more active role in system development. ► The developers & the user spend less time & effort developing the system. ► Implementation is much easier because the user knows what to expect.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 20 Potential Pitfalls of Prototyping ► The haste to deliver the prototype may produce shortcuts in problem definition, alternative evaluation, & documentation. The shortcut produces a “quick & dirty” effort. ► The user may get overly excited about the prototype, leading to unrealistic expectations regarding the production system. ► Evolutionary prototypes may not be very efficient. ► The computer-human interface provided by certain prototyping tools may not reflect good design techniques.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 21 Rapid Application Development ► Rapid Application Development (RAD), is a term coined by James Martin. It refers to a development life cycle intended to produce systems quickly without sacrificing quality. ► Information engineering is the name that Martin gives to his overall approach to system development, which treats it as a firm-wide activity. ► Enterprise is used to describe the entire firm. ► Essential to RAD is management, people, methodologies, & tools. ► Best suited for large systems.

© 2007 by Prentice HallManagement Information Systems, 10/e Raymond McLeod and George Schell 22 Figure 7.7 Rapid Application Development