Management Information Systems 10e Raymond Mc Leod and

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

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

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 Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 3

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 Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 4

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 1960 s/early 1970 s, 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 Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 5

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 Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 6

Figure 7. 1 Phases & Steps of Systems Approach © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 7

Figure 7. 2 Each Business Area is a System © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 8

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 Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 9

Figure 7. 3 Analyze System Parts in Sequence © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 10

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 Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 11

Systems Development Lifecycle ► Methodology adalah cara yang dianjurkan untuk melakukan sesuatu ► Systems development lifecycle (SDLC) adalah penerapan dari pendekatan sistem ke dalam proses pembangunan sistem informasi ► Tahapan Traditional SDLC : § § § Planning Analysis Design Implementation Use. © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 12

Figure 7. 4 Circular Pattern of the System Life Cycle © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 13

Prototyping ► Prototype adalah versi awal (potensial) dari sistem yg memberi developer dan pengguna gambaran bagaimana sistem dlm bentuk lengkapnya akan bekerja ► Prototyping adalah proses untuk menghasilkan prototype ► Paling cocok untuk sistem kecil © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 14

Evolutionary Prototype ► Evolutionary prototype adalah prototype yang terus-menerus diperbaiki sampai semua fungsi yang diperlukan user dipenuhi. Langkah 2 -nya mencakup: § Identifikasi kebutuhan user § Membangun prototype § Menentukan apakah prototype bisa diterima § Gunakan prototype tsb © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 15

Figure 7. 5 Development of Evolutionary Prototype © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 16

Requirements Prototype ► Requirements prototype dibangun sebagai sarana untuk mendefinisikan kebutuhan fungsional dr sistem baru ketika user tidak bisa menyampaikan dengan pasti apa yang mereka butuhkan ► Awali dg Langkah 2 Evolutionary Prototype kmdian langkah selanjutnya adalah: § § Lakukan koding sistem baru Lakukan test sistem baru Tentukan apakah sistem baru bisa diterima Gunakan sistem © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 17

Figure 7. 6 Development of Requirements Prototype © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 18

Hal 2 yg menarik dari Prototyping ► Komunikasi antara developer dengan user meningkat ► Developer dapat berkerja lebih baik dalam menentukan kebutuhan user. ► User memainkan peran yang lebih aktif dalam pembangunan sistem ► Developer dan pengguna menghabiskan waktu dan usaha lebih sedikit dalam pembangunan sistem ► Implementasi menjadi jauh lebih mudah karena user tahu apa yang diharapkan. © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 19

Potensi kegagalan Prototyping ► Keinginan untuk cpt menghasilkan protype mungkin akan menghasilkan definisi masalah yang kurang bagus ► Pengguna mgkin menjadi terlalu bersemangat thd prototype yang bisa membawa kepada harapan yang tidak realistis thd sistem baru ► Evolutionary prototypes mungkin tdk efisien © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 20

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 Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 21

Figure 7. 7 Rapid Application Development © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 22

Phased Development ► Phased development adalah pendekatan pembangunan sistem informasi yang terdiri dari 6 tahapan: § § § Preliminary investigation Analysis Design Preliminary construction System test Installation. ► Cocok © 2007 by Prentice Hall untuk sistem dengan semua ukuran. Management Information Systems, 10/e Raymond Mc. Leod and George Schell 23

Figure 7. 8 Stages of Phases Development © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 24

Module Phases ► System seperti: dibagi ke dalam modul 2 besar § Pembuat Laporan; § Database; § Web interface. ► Jumlah modul bervariasi dari 1 sampai 12 atau lebih ► Tahapan 2 dilakukan secara terpisah untuk masing 2 modul © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 25

Figure 7. 9 Module Phase of Systems Development © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 26

Business Process Redesign ► Reengineering or Business process redesign (BPR) adlh proses mengerjakan ulang sistem. § Sistem mencakup baik sistem yang memproses data perusahaan dan sistem yang melakukan fungsi dasar seperti pengeboran minyak. ► BPR mempengaruhi operasi IT perusahaan dg 2 jalan: § Membantu dlm desain ulang sistem informasi lama § Dgunakan dalam desain ulang sistem informasi untuk mendukung operasi besar perusahaan ► Biasanya strategis © 2007 by Prentice Hall dimulai pada tingkat manajemen Management Information Systems, 10/e Raymond Mc. Leod and George Schell 27

Figure 7. 10 Top-Down Initiation of BPR Projects © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 28

Strategic Initiation of BPR ► Reverse engineering is the process of analyzing an existing system to: § identify its elements & their interrelationships; § Create documentation at a higher level of abstraction than currently exists. ► Functionality is the job that it performs. ► Reengineering is the complete redesign of a system with the objective of changing its functionality. ► Forward engineering is given to the process of following the SDLC in the normal manner while engaging in BPR. © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 29

BPR Components ► BPR components can be applied separately or in combination. ► Functional quality is a measure of what the system does. ► Technical quality is a measure of how well it does it. © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 30

Figure 7. 11 BPR Component Selection © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 31

Methodologies in Perspective ► Traditional SDLC is an application of the systems approach to the problem of system development; contains all elements. ► Prototyping is an abbrev. form focusing on the definition & satisfaction of user needs. ► RAD is an alternative approach to the design & implementation phases of SDLC. ► Phased development uses traditional SDLC & applies it in a modular fashion. © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 32

System Development Tools ► Process modeling was first done with flowcharts. § ISO standards § Use of 20+ symbols ► Data flow diagrams (DFD) is a graphic representation of a system that uses four symbol shapes to illustrate how data flows through interconnected processes. . ► DFDs are excellent for modeling processes at a summary level. © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 33

Data Flow Diagram Symbols ► Terminator describes an environmental element, such as a person, organization, or another system. § Environmental elements exist outside the boundary of the system. Process is something than transforms input into output. ► Data flow consists of a group of logically related data elements that travel from one point or process to another; can diverge and converge. ► Data storage is a repository of data. ► Connector contains the number of the process that provides the data flow. ► © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 34

Figure 7. 12 DFD of a Sales Commission System © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 35

Leveled Data Flow Diagrams Leveled DFDs is used to describe the hierarchy of diagrams, ranging from context to lowest-level n diagram. ► Figure 0 diagram identifies the major processes of a system. ► § Use additional DFDs to achieve documentation at both a more summarized & a more detailed level. ► Context diagram is a diagram that documents the system at a more summarized level. § Positions the system in a environmental context. ► Figure n diagram is a diagram that provides more detail. § n represents the # of processes on the next higher level. § Documents a single process of a DFD in greater detail. © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 36

Figure 7. 13 Context Diagram of a Sales Commission System © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 37

Figure 7. 14 Figure 4 Diagram of a Sales Commission System © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 38

Use Cases ► Use case is a narrative description in an outline form of the dialog that occurs between a primary & secondary system. ► Continuous narrative format with each action numbered sequentially. ► Ping-pong format consists of two narratives & the numbering indicates how the tasks alternate between the primary & secondary systems. ► Alternative events are actions that are not normally expected to occur; alphabetic letters are appended to step numbers. © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 39

Figure 7. 15 A Use Case © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 40

Figure 7. 16 Use Case Guidelines © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 41

Project Management ► Steering committee is a committee with the purpose of providing ongoing guidance, direction, & control of all systems projects. ► MIS steering committee purpose is directing the use of the firm’s computing resources. § It establishes policies. § It provides fiscal control. § It resolves conflict. © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 42

Figure 7. 17 Managers of a System Life Cycle Arranged in a Hierarchy © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 43

Project Leadership ► Project team includes all of the persons who participate in the development of an information system. ► Team leader (project leader) provides direction throughout the life of the project. © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 44

Project Management Mechanism ► Basis for project management is the project plan. ► Gantt chart is a horizontal bar chart that includes a bar for each task to be performed; bars arranged in time sequence. ► Network diagram (CPM diagram, PERT chart) is a drawing that identifies activities & links them with arrows to show the sequence in which they are to be performed. ► Narrative reports are in the form of weekly written reports by project leader, communicates project information to MIS steering committee. © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 45

Figure 7. 18 A Gantt Chart © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 46

Figure 7. 19 A Network Diagram © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 47

Project Cost-Estimating ► Cost-estimating inputs § § ► Cost-estimating tools & techniques § § § ► Work breakdown structure (WBS) Resource requirements, resource rates Activity duration estimates Historical information Bottom-up estimating Computerized estimating Mathematical models Cost-estimating outputs § Supporting details § Cost-management plan © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 48

Table 7. 1 Components of Cost. Estimating Process © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 49

Table 7. 2 Example of Project Cost © 2007 by Prentice Hall Management Information Systems, 10/e Raymond Mc. Leod and George Schell 50