DECISION SUPPORT SYSTEM 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

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

Skills for Project Managers Technology and business knowledge Judgment Negotiation Good communication Organization

THE TRADITIONAL SYSTEM DEVELOPMENT LIFE CYCLE Need Planning Analysis Design Implementation System

PLANNING 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

ANALYSIS 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.

DESIGN 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.

IMPLEMENTATION 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

CASE 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

Visible Analyst Courtesy of Visible System Corporation

ALTERNATIVE DEVELOPMENT METHODOLOGIES 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 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

Methods a) Phased development b) Prototyping c) Throwaway prototyping 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

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

Prototyping Need Planning Analysis Design Implementation Prototype Prototype Not OK Prototype OK System

Throwaway Prototyping Need Planning Analysis Design Design Implementation Design Prototype Not OK Implementation System Design Prototype

Prototyping for DSS Development Problems are semistructured or unstructured Managers and developers may not completely understand problem Use 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

Advantages of Prototyping Short development time Short user reaction time Improved user understanding Low cost

DSS TECHNOLOGY LEVELS AND TOOLS Specific DSS DSS Generations DSS Tools Technology levels DSS Primary tools DSS Integrated tools Specific DSS

DSS 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

DSS 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.

SPECIFIC DSS Final product or the DSS application

DSS DEVELOPMENT PLATFORMS General purpose programming language Fourth-generation language (4 GL) OLAP with a data warehouse or a large database DSS integrated development tool CASE methodology

DSS DEVELOPMENT TOOL SELECTION Hardware selection -- from individual PC’s to Multiprocessor computers -- existing hardware architecture of the Organisation & no. of Users Software selection -- DSS information requirements & Outputs -- Large DSS might be developed with different tools -- Technical, functional, end-user and managerial issues DSS generator selection

TEAM-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

END 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.

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