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Systems Analysis

Requirements Modeling. Systems Analysis. SDLC Phases. Phase 2: Systems Analysis Objectives Develop a logical model of the proposed system Learn about requirements modeling, data and process modeling, and object modeling Consider the transition from logical to physical design. Chapter 3.

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Systems Analysis

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  1. Requirements Modeling Systems Analysis

  2. SDLC Phases Phase 2: Systems Analysis Objectives • Develop a logical model of the proposed system • Learn about requirements modeling, data and process modeling, and object modeling • Consider the transition from logical to physical design Systems Analysis and Design Fourth Edition

  3. Chapter 3 Requirements Modeling Systems Analysis and Design Fourth Edition

  4. Objectives • Explain systems analysis phase activities and the end product of the systems analysis phase • Describe joint application development (JAD) Systems Analysis and Design Fourth Edition

  5. Objectives • Explain how functional decomposition diagrams (FDD) are used during systems development • List and describe system requirements, including outputs, inputs, processes, performance, and controls • Explain the importance of scalability in system design Systems Analysis and Design Fourth Edition

  6. Objectives • Define total cost ownership (TCO) and explain the concept • Describe how to conduct a successful interview Systems Analysis and Design Fourth Edition

  7. Objectives • Explain when and how to use fact-finding techniques, including interviews, documentation review, observation, questionnaires, sampling, and research • Develop effective documentation methods to use during systems development Systems Analysis and Design Fourth Edition

  8. Overview of systems analysis phase Fact-finding techniques Interviewing Documentation review Observation Surveys and Questionnaires Sampling Research Methods used to record results Introduction Systems Analysis and Design Fourth Edition

  9. Systems AnalysisPhase Overview • Systems analysis phase tasks • Requirements Modeling • Data and Process Modeling • Object Modeling • Transition to Systems Design • Two steps in the requirement modeling phase • Requirements determination (fact-finding) • Requirements analysis Systems Analysis and Design Fourth Edition

  10. Systems AnalysisPhase Overview Systems Analysis and Design Fourth Edition

  11. Systems Development Methods • Joint Application Development (JAD) • JAD team approach • JAD Participants and Roles • JAD project leader • Top management • Managers • Users • IT staff members • Recorder Systems Analysis and Design Fourth Edition

  12. Systems Development Methods • Joint Application Development (JAD) • JAD Agenda • Introduce team members and discuss objectives • Explain reason for project • Present outline of issues to be investigated • Open discussion to identify specific issues • Discuss system requirements • Develop models Systems Analysis and Design Fourth Edition

  13. Systems Development Methods • Joint Application Development (JAD) • JAD Agenda (continued) • Present issues to be addressed • Review results • Decide on main issues • Document all topics • Recap JAD session • Prepare report for all JAD members Systems Analysis and Design Fourth Edition

  14. Modeling Tools and Techniques • Functional Decomposition Diagrams • A functional decomposition diagram (FDD) is a top-down representation of business functions and processes Systems Analysis and Design Fourth Edition

  15. Modeling Tools and Techniques Systems Analysis and Design Fourth Edition

  16. Systems Requirements Checklist • Characteristics or features that must be included to satisfy business requirements • Outputs • Inputs • Processes • Performance • Controls Systems Analysis and Design Fourth Edition

  17. Scalability and Total Cost of Ownership • Scalability • The ability to adjust system capacity as business requirements change • Total Cost of Ownership • The sum of the direct costs and indirect expenses • Systems developers must identify and document indirect expenses: a system that seems inexpensive initially might turn out to be the most expensive Systems Analysis and Design Fourth Edition

  18. Fact-Finding • Overview • Software helps you gather and analyze facts; however, it cannot perform fact-finding for you • First step to fact-finding is identifying the information you need • Create a fact-finding plan Systems Analysis and Design Fourth Edition

  19. Fact-Finding • Who, What, When, Where, and How? • Who performs the procedures within the system? • What is being done? • Where are operations being performed? • When is a procedure performed? • How is a procedure performed? • Another important question • Why? Systems Analysis and Design Fourth Edition

  20. Fact-Finding Systems Analysis and Design Fourth Edition

  21. Fact-Finding Techniques • Interviews • Document review • Observation • Surveys and questionnaires • Sampling • Research Systems Analysis and Design Fourth Edition

  22. Interviews • Determine the people to interview • Establish objectives for the interview • Develop interview questions • Prepare for the interview • Conduct the interview • Document the interview • Evaluate the interview Systems Analysis and Design Fourth Edition

  23. Document Review • Document review • Review existing system documentation • Obtain copies of actual forms and documents • Review blank copies of forms • Review samples of completed forms • Review software documentation Systems Analysis and Design Fourth Edition

  24. Observation • Observation • Ask questions about present system operation • Observe all steps in the processing cycle • Examine each form, record, and report • Consider each person working with the system • Talk to people who receive current reports • Consider the Hawthorne Effect Systems Analysis and Design Fourth Edition

  25. Questionnaires and Surveys • Questionnaires and surveys • Brief and user-friendly • Clear instructions • Questions in logical order • Simple wording to avoid misunderstanding • Avoid leading questions • Open-ending questions are difficult to tabulate • Limit questions raising concern/negative issues • Section for general comments • Test the questionnaire in advance Systems Analysis and Design Fourth Edition

  26. Sampling • Sampling • Collect examples of actual documents • Sampling techniques • Systematic sample • Stratified sample • Random sample • Main objective is to ensure representation of the overall population accurately • Sampling should be considered for interviewing or questionnaires Systems Analysis and Design Fourth Edition

  27. Other Fact-Finding Techniques • Research • Journals, periodicals, books • Internet sites • Hardware and software vendors • Independent firms that provide information • Newsgroups • Professional meetings, seminars, discussions • Site visits to observe a system in use Systems Analysis and Design Fourth Edition

  28. Other Fact-Finding Techniques • Interviews vs. questionnaires • Interview • Need information from only a few people • More familiar and personal • Can be costly and time-consuming • Questionnaire • Many people able to provide input • People may offer more candid responses • If not designed well, may be viewed as intrusive Systems Analysis and Design Fourth Edition

  29. Documentation • The need for recording the facts • Keeping accurate records is essential • Basic rule: write it down • Guidelines for good documentation • Record information as soon as possible • Use the simplest recording method • Ensure that your work is understandable • Organize your documentation material • Consider a narrative list with simple statements Systems Analysis and Design Fourth Edition

  30. Recording the Facts • Software tools • CASE tools • Word processing • Spreadsheets • Database • Presentation graphics • Personal information managers Systems Analysis and Design Fourth Edition

  31. EndChapter 3

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