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This comprehensive guide provides the roadmap for developing information systems, covering aspects like strategic analysis, enterprise analysis, and systems design. It outlines critical success factors, problem areas, implementation strategies, and methodologies to ensure successful system development and implementation.
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11 SYSTEMS DEVELOPMENT
Information Systems Plan Road map indicating direction of system development: • Goals/Rationale • Current situation • New developments • Management decisions • Implementation plan • Budget
Enterprise Analysis Business system planning (BSP): Helps identify key entities & attributes in organization’s data Analysis of organization-wide information needs in terms of: • Organizational units • Functions • Processes • Data elements
Strategic Analysis Critical Success Factors (CSF) • A small number of easily identifiable operational goals • Shaped by industry, manager, environment • Believed to assure firm’s success • Used to determine organization’s information requirements
IS Problem Areas Design • User interface • Doesn’t do what intended to do Data • Data accuracy & consistency Cost • Too expensive to run • Too expensive to complete Operations • System does not run well
Model of Organizational Change • Unfreezing • Prepare those affected by change • Communicate reasons • Solicit feedback • Moving • Training of those affected by change • Refreezing • Routinization of the change • Becomes “second nature”
Causes of Implementation Success & Failure • The role of users in the implementation process • The degree of management support • Level of complexity and risk • Quality of management of the implementation process
Level of Complexity & Risk • Project Size • Larger projects higher risk • Large = cost, size of staff, time to implement • Project Structure • Lower structure higher risk • Structure = requirements inputs and outputs known • Experience with technology • Lower experience higher risk • Experience of project team and info systems staff
Systems Analysis Analysis of problem to be solved with an information system • Feasibility study: Can problem be solved within constraints? • Financial - Legal • Technical - Organizational • Establish Information Requirements • Identifies who needs what information, and when, where and how it is needed
Systems Design Details how a system will meet the information requirements • User Interface • Database Design • Processing • Security • Conversion • Training • Organizational change
Completing Systems Development • Programming • Translate system specifications into program code • Testing • Unit testing (test each program) • System testing (tests info system as a whole) • Acceptance testing (final testing, evaluated by users) • Test plan
Conversion • Parallel approach • Old and new systems used together until assured that new system functions correctly • Direct cutover • New system completely replaces old one on an appointed day • Pilot study • New system introduced to a limited area of the organization • Phased approach • New system introduced in stages by function
Production and Maintenance • Operate the system • Evaluate the system • Modify the system and relevant documentation
Prototyping • Identify basic user’s requirements • Develop an initial prototype • Use prototype • Revise & enhance prototype
Application Software Packages Prewritten, precoded application software, commercially available for sale or lease • Geared to common requirements • Customization • Modification of software to meet organization’s needs • Benefits of using packages whittled away by excessive changes
End User Development End users develop systems,using fourth generation tools, with little assistance from technical experts,
Outsourcing Contracting applications development, or computing centre operations, to external vendors
Other methodologies • Object-oriented development • Combines data and procedures to create objects • reusability • Unified Modelling Language (UML) • Notation for logical representations of objects
Other methodologies • Rapid Application Development (RAD) • Develops system in a short timeframe • Uses prototyping, fourth-generation tools and teamwork • Joint Application Design (JAD) • Process to accelerate the generation of user requirements • End users + information system specialists work in intensive, interactive design sessions