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CHAPTER 6 Decision Support Systems Development 1 CHAPTER 6 Decision Support Systems Development 1

Decision Support System Development n How to develop a DSS n DSS must usually Decision Support System Development n How to develop a DSS n DSS must usually be custom tailored Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 2

System Development Issues n n n n System development life cycle (SDLC) Prototyping Forming System Development Issues n n n n System development life cycle (SDLC) Prototyping Forming the development team Complex process Technical issues Behavioral issues Different approaches Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 3

Development Life Cycle (SDLC) (Waterfall) Need Planning Analysis Design Implementation System Decision Support Systems Development Life Cycle (SDLC) (Waterfall) Need Planning Analysis Design Implementation System Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 4

Fundamental SDLC Phases n n Planning Analysis Design Implementation Steps and deliverables follow Decision Fundamental SDLC Phases n n Planning Analysis Design Implementation Steps and deliverables follow Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 5

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Planning Why Build the System? Minor Step Deliverable 1. Identify business value 2. Analyze Planning Why Build the System? Minor Step Deliverable 1. Identify business value 2. Analyze feasibility 3. Develop work plan 4. Staff project System request Feasibility study Work plan Staffing plan, Project charter Project management tools CASE tool Standards list Project binders / files Risk assessment 5. Control and direct project Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 7

Analysis Who, What, When, Where? Minor Step Deliverable 6. Analyze problem Analysis plan 7. Analysis Who, What, When, Where? Minor Step Deliverable 6. Analyze problem Analysis plan 7. Gather information Information 8. Model process(es) Process model 9. Model data Data model Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 8

Design How Will the System Work? Minor Step Deliverable 10. Design physical system Design Design How Will the System Work? Minor Step Deliverable 10. Design physical system Design plan 11. Design architecture Architecture design, Infrastructure design 12. Design interface Interface design 13. Design database and files Data storage design 14. Design program(s) Program design Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 9

Implementation System Delivery Minor Step Deliverable 15. Construction Test plan, Programs, Documentation 16. Installation Implementation System Delivery Minor Step Deliverable 15. Construction Test plan, Programs, Documentation 16. Installation Conversion plan, Training plan Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 10

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Common Implementation Headaches (DSS in Focus 6. 4) n n n n No project Common Implementation Headaches (DSS in Focus 6. 4) n n n n No project team or management support Hazy purpose; no defined schedule; ballooning scope Unclear aspects of make vs. buy decisions Few project integrations are functional out of the box Qualitative benefits No user buy in Poor project management skills No accountability / no responsibility Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 12

CASE Tools n n n Information systems for systems analysts Can help manage system CASE Tools n n n Information systems for systems analysts Can help manage system development Upper CASE (assists in analysis) Lower CASE (manages diagrams and code generation) Integrated CASE (both) Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 13

CASE Tools n n n n Oracle Enterprise Development Suite Rational Rose Paradigm Plus CASE Tools n n n n Oracle Enterprise Development Suite Rational Rose Paradigm Plus Visible Analyst Logic Works Suite Axiom. Sys and Axiom. Dsn V 32 & X 32 Visual Studio Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 14

Visible Analyst Courtesy of Visible System Corporation (Figure 6. 2) Decision Support Systems and Visible Analyst Courtesy of Visible System Corporation (Figure 6. 2) Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 15

Project Management (PM) n n n Team leader must have good PM skills Major Project Management (PM) n n n Team leader must have good PM skills Major reason for IS development failures -bad PM skills Only 26% of all projects surveyed (23, 000) in 1998 succeeded 28% failed, 46% challenged Lower success rates for large companies Better PM skills needed Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 16

Skills for Project Managers n n n Technology and business knowledge Judgment Negotiation Good Skills for Project Managers n n n Technology and business knowledge Judgment Negotiation Good communication Organization Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 17

Implementation Failures (DW Example) n n n No user involvement No clear objectives stated Implementation Failures (DW Example) n n n No user involvement No clear objectives stated early No real executive sponsorship More in DSS in Focus 6. 5 Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 18

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Alternative Development Methodologies n n Parallel development Rapid application development (RAD) methodologies n n Alternative Development Methodologies n n Parallel development Rapid application development (RAD) methodologies n n n Phased development Prototyping Throwaway prototyping Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 20

Parallel Development n n n Multiple copies of design and implementation phases To develop Parallel Development n n n Multiple copies of design and implementation phases To develop separate subsystems All come together in a single implementation phase Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 21

Phased Development n n n Break system up into versions developed sequentially Each version Phased Development n n n Break system up into versions developed sequentially Each version has more functionality Evolves into a final system Users gain functionality quickly But initial systems are incomplete Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 22

Prototyping n n Performing analysis, design, and implementation phases concurrently, and repeatedly Users see Prototyping n n Performing analysis, design, and implementation phases concurrently, and repeatedly Users see system functionality quickly and provide feedback Decision maker learns about problem But can lose gains in repetition Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 23

Prototyping (Figure 6. 3) Need Planning Analysis Design Implementation Prototype Not OK Prototype OK Prototyping (Figure 6. 3) Need Planning Analysis Design Implementation Prototype Not OK Prototype OK System Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 24

Throwaway Prototyping n n n Like prototyping and SDLC Analysis phase is thorough Design Throwaway Prototyping n n n Like prototyping and SDLC Analysis phase is thorough Design prototypes assist in understanding the system Example: can use Excel, then Visual Basic (Figure 6. 4) Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 25

Throwaway Prototyping (Figure 6. 4) Need Planning Analysis Design Prototype Not OK Implementation System Throwaway Prototyping (Figure 6. 4) Need Planning Analysis Design Prototype Not OK Implementation System Design Prototype Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 26

Prototyping for DSS Development n n n Problems are semistructured or unstructured Managers and Prototyping for DSS Development n n n Problems are semistructured or unstructured Managers and developers may not completely understand problem Use prototyping Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 27

Prototyping Terms n n n Iterative design Evolutionary development Middle-out process Adaptive design Incremental Prototyping Terms n n n Iterative design Evolutionary development Middle-out process Adaptive design Incremental design Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 28

Prototyping (Figure 6. 3 again) Need Planning Analysis Design Implementation Prototype Not OK Prototype Prototyping (Figure 6. 3 again) Need Planning Analysis Design Implementation Prototype Not OK Prototype OK System Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 29

Why Prototyping? n n n Users and managers involved in every phase and iteration Why Prototyping? n n n Users and managers involved in every phase and iteration Learning is part of design Prototyping bypasses the information requirement definition (step 7) Short interval between iterations Initial prototype must be low cost Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 30

Advantages of Prototyping n Short development time n Short user reaction time n Improved Advantages of Prototyping n Short development time n Short user reaction time n Improved user understanding n Low cost Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 31

Disadvantages of Prototyping n n n Lack of a thorough understanding IS’s benefits and Disadvantages of Prototyping n n n Lack of a thorough understanding IS’s benefits and costs- not using SDLC Lack of a detailed description of information needs Lack of an easy to maintain IS design Lack of a well-tested IS Unprepared users- not using SDLC Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 32

DSS Technology Levels and Tools n Three Levels of DSS Technology n n Plus DSS Technology Levels and Tools n Three Levels of DSS Technology n n Plus n n n Specific DSS [the application] DSS integrated tools (generators) [Excel] DSS primary tools [programming languages] DSS integrated tools Now all with Web hooks and easy GUI interfaces Relationships among the three levels (Figure 6. 5) Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 33

DSS Technology Levels (Figure 6. 5) Specific DSS Generators (Spreadsheets, …) DSS Tools (Languages, DSS Technology Levels (Figure 6. 5) Specific DSS Generators (Spreadsheets, …) DSS Tools (Languages, …) Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 34

DSS Development Platforms n n n n General-purpose programming language Fourth-generation language (4 GL) DSS Development Platforms n n n n General-purpose programming language Fourth-generation language (4 GL) OLAP with a data warehouse or large database DSS integrated development tool (generator, engine) Domain-specific DSS generator Use the CASE methodology Integrate several of the above Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 35

Hardware Selection n PCs Unix workstations Network of Unix workstations Web servers Mainframes n Hardware Selection n PCs Unix workstations Network of Unix workstations Web servers Mainframes n Typically use existing hardware n n Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 36

Software Selection Complex because n n n At start, information requirements, etc. are unknown Software Selection Complex because n n n At start, information requirements, etc. are unknown Hundreds of packages Software updated rapidly Price changes Many people involved in decision Language capability problems (More) Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 37

n Different tools might be needed Many criteria Technical, functional, end-user, and managerial issues n Different tools might be needed Many criteria Technical, functional, end-user, and managerial issues Inaccurate published software reviews Might prefer a single vendor n Maybe use the AHP!!! n n Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 38

Team-Developed DSS n n Substantial effort Extensive planning and organization Some generic activities Group Team-Developed DSS n n Substantial effort Extensive planning and organization Some generic activities Group of people to build and to manage it Size depends on n n Effort Tools Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 39

Team-Developed Versus User. Developed DSS n n DSS 1970 s and early 1980 s Team-Developed Versus User. Developed DSS n n DSS 1970 s and early 1980 s Large-scale, complex systems Primarily provided organizational support Team efforts Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 40

End-User-Developed Systems n n n n n Personal computers Computer communication networks PC-mainframe communication End-User-Developed Systems n n n n n Personal computers Computer communication networks PC-mainframe communication Friendly development software Reduced cost of software and hardware Increased capabilities of personal computers Enterprise-wide computing Easy accessibility to data and models Client/server architecture Now OLAP Balance Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 41

Organizational Placement of the DSS Development Group 1. 2. 3. 4. 5. 6. Information Organizational Placement of the DSS Development Group 1. 2. 3. 4. 5. 6. Information services (IS) department Highly placed executive staff group Finance or other functional area Industrial engineering department Management science group Information center group Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 42

End-user Computing and User-Developed DSS n n End-user Computing (end-user development): development and use End-user Computing and User-Developed DSS n n End-user Computing (end-user development): development and use of computer-based information systems by people outside the formal information systems areas End-users n n At any level of the organization In any functional area Levels of computer skill vary Growing Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 43

User-Developed DSS Advantages 1. Short delivery time 2. Eliminate extensive and formal user requirements User-Developed DSS Advantages 1. Short delivery time 2. Eliminate extensive and formal user requirements specifications 3. Reduce some DSS implementation problems 4. Low cost Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 44

User-Developed DSS Risks 1. Poor Quality 2. Quality Risks n n n Substandard or User-Developed DSS Risks 1. Poor Quality 2. Quality Risks n n n Substandard or inappropriate tools and facilities Development process risks Data management risks 3. Increased Security Risks 4. Problems from Lack of Documentation and Maintenance Procedures Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 45

Issues in Reducing End. User Computing Risks n n n Error detection Use of Issues in Reducing End. User Computing Risks n n n Error detection Use of auditing techniques Determine the proper amount of controls Investigate the reasons for the errors Solutions Spreadsheet errors n Should use same controls as normal IS Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 46

Developing DSS: Putting the System Together n Development tools and generators Use of highly Developing DSS: Putting the System Together n Development tools and generators Use of highly automated tools Use of prefabricated pieces n Both increase the developer’s productivity n n Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 47

DSS Development System Includes n n n Request (query) handler System analysis and design DSS Development System Includes n n n Request (query) handler System analysis and design facility Dialog management system Report generator Graphics generator Source code manager (more) Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 48

n n n n Model base management system Knowledge-base (management) system Object-oriented tools Standard n n n n Model base management system Knowledge-base (management) system Object-oriented tools Standard statistical and management science tools Special modeling tools Programming languages Document imaging tools Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 49

DSS Development System Components n n n Some may be integrated into a DSS DSS Development System Components n n n Some may be integrated into a DSS generator Others may be added as needed Components used to build a new DSS Core of system includes development language or DSS generator Construction by combining programming modules Windows environment handles the interface Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 50

DSS Research Directions and The DSS of the Future n n n n n DSS Research Directions and The DSS of the Future n n n n n More AI Faster, more powerful computers The Web - interfaces and DB and model access More and better GSS ERM/ERP Knowledge management Better GUI Better telecommunications More research on theories More research on methods Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 51

Summary n n n n DSS are complex and their development can be too Summary n n n n DSS are complex and their development can be too SDLC Prototyping DSS technologies DSS teams or individuals End user computing Tool and generator selection can be tricky DSS research continues Decision Support Systems and Intelligent Systems, Efraim Turban and Jay E. Aronson, 6 th edition Copyright 2001, Prentice Hall, Upper Saddle River, NJ 52