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DECISION SUPPORT DECISION SUPPORT SYSTEM DEVELOPMENTSYSTEM DEVELOPMENT

• The Traditional SDLC

• Alternate Development Methodologies

• Prototyping

• DSS Technology Levels and Tools

• DSS Development Platforms

• DSS Development Tool Selection

• Team Developed DSS

• End User Developed DSS

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Project Management (PM)Project Management (PM)

• 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

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Skills for Project ManagersSkills for Project Managers

• Technology and business knowledge

• Judgment

• Negotiation

• Good communication

• Organization

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THE TRADITIONAL SYSTEM THE TRADITIONAL SYSTEM DEVELOPMENT LIFE CYCLEDEVELOPMENT LIFE CYCLE

Need

Planning

Design

Implementation

System

Analysis

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PLANNINGPLANNING

• Business needs not being met

• possible opportunities identified through environment scanning

• feasibility analysis is conducted for project initiation

• technical, cost and organization feasibility are considered

• if the project is approved the staffing is planned

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ANALYSISANALYSIS

• who will be the users ?

• what will be the systems output ?

• where and when it will run ?

• starts with the development of analysis strategy.

• if there is an existing system, it is analyzed, along with the ways of moving to the new system.

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DESIGNDESIGN

• indicates how system will work

• all details of hardware, software, network infrastructure, user interface are all considered

• user interface forms, displays, reports and programs, database and files are specified

• amount of system to be purchased or contracted is decided-on.

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IMPLEMENTATIONIMPLEMENTATION

• involves not only building the system but also testing it to verify that it works

• better planning will result in fewer bugs

• installation is the last step and involves actually getting the system up and running

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CASE TOOLSCASE TOOLS

• for complex projects, the SDLC should be managed with CASE tools

• these tools are information systems for systems analyst and can help manage every aspects of developing a system

• upper CASE tools (analysis phase)

• lower CASE tools (code)

• I-CASE tools (both)

• oracle enterprise development suite, rational rose, paradigm plus, visible analyst, logic works suite

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Visible AnalystVisible Analyst Courtesy of Visible System Corporation Courtesy of Visible System Corporation

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ALTERNATIVE DEVELOPMENT ALTERNATIVE DEVELOPMENT METHODOLOGIESMETHODOLOGIES

1 Parallel Development

• the design and implementation phases split into multiple copies

• involves development of a separate subsystem or subproject

• A systems integrator puts the pieces together in a cohesive system while implementing

2 Rapid Application Development Methodologies

• will adjust the SDLC in such away that parts of a system can be developed quickly and users can obtain some functionality as soon as possible

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Methods

a) Phased development

b) Prototyping

c) Throwaway prototyping

a) Phased development

• involves breaking a system into a series or versions that are developed sequentially

• each version has more functionality than the previous one

• user will gain functionality quickly

• system is incomplete by design

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b) Prototyping• involves performing the analysis, design and implementation phases

concurrently and repeatedly• system prototypes are quickly developed and demonstrated to users• feedback is obtained, and the system can be modified on moving to the

next prototype

c) Throwaway prototyping• design prototypes are developed to assist in understanding more about

the system being developed• developed as pilot tests on simple development platforms to learn about

user requirements and the final system to be deployed• once the pilot test is successful, the prototype is discarded and a

preliminary design of the real systems takes place

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Prototyping Prototyping

Design

Implementation

Analysis

Need

Planning

Prototype

System

Prototype Not OKPrototype OK

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Throwaway Prototyping Throwaway Prototyping

Design

Implementation

Analysis

Need

Planning

DesignPrototype

System

Design PrototypeNot OK

Design

Implementation

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Prototyping for DSS DevelopmentPrototyping for DSS Development

• Problems are semistructured or unstructured

• Managers and developers may not completely understand problem

• Use prototyping

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Why Prototyping?Why Prototyping?

• Users and managers involved in every phase and iteration

• Learning is part of design

• Prototyping bypasses the information requirement definition

• Short interval between iterations

• Initial prototype must be low cost

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Advantages of PrototypingAdvantages of Prototyping

• Short development time

• Short user reaction time

• Improved user understanding

• Low cost

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DSS TECHNOLOGY LEVELS DSS TECHNOLOGY LEVELS AND TOOLSAND TOOLS

Specific DSS

DSS Tools

DSS Generations

Technology levels

DSS Primary tools DSS Integrated tools Specific DSS

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DSS PRIMARY TOOLSDSS PRIMARY TOOLS

• Lowest level of DSS technology

• Facilitate the development of either the DSS generator or a specific DSS

• Examples of these tools are programming languages, graphics, editors, query systems and random numbers generators

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DSS INTEGRATED TOOLSDSS INTEGRATED TOOLS

• Integrated development software package

• Provides a set of capabilities for building specific DSS

• Quick, inexpensive and easy

• Capabilities ranging from modeling, report generation and graphical display to performing risk-analysis.

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SPECIFIC DSSSPECIFIC DSS

• Final product or the DSS application

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DSS DEVELOPMENT DSS DEVELOPMENT PLATFORMSPLATFORMS• General purpose programming language

• Fourth-generation language (4 GL)

• OLAP with a data warehouse or a large database

• DSS integrated development tool

• CASE methodology

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DSS DEVELOPMENT TOOL DSS DEVELOPMENT TOOL SELECTIONSELECTION1 Hardware selection

-- from individual PC’s to Multiprocessor computers

-- existing hardware architecture of the Organisation & no. of Users

2 Software selection

-- DSS information requirements & Outputs

-- Large DSS might be developed with different tools

-- Technical, functional, end-user and managerial issues

3 DSS generator selection

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TEAM-DEVELOPED DSSTEAM-DEVELOPED DSS

A group of people from different categories such as users, intermediaries, DSS developers, technical support experts, and IS personnel who join together to develop a particular DSS is called a Team-Developed DSS. Team-Developed DSS is a complex, lengthy and costly process.

• Need extensive planning and organization

• The team members may be as few as 2-3 people or as many as 12-15 people

• The no of members depends on the nature of DSS application and the tools used for developing the DSS

• The team may be temporary or permanent

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END USER-DEVELOPED DSSEND USER-DEVELOPED DSS

End- user computing / End-user development is the development and use of computer-base information systems by people outside the formal information system area.

User-developed DSS includes decision makers and professionals who build or use computers directly to solve problems or enhance their productivity.

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ADVANTAGE

• Delivery time is short

• No need for IS development team

• DSS implementation problems are reduced

• Cost is very low

DISADVANTAGE

• Can lead to low-quality system

• Security risk

• Lack of documentation and maintenance procedures may cause problems

• Quality risks: Substandard, inappropriate tools and facilities used in DSS development