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IMS9001 - Systems Analysis and Design

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  2. Systems analysis • Systems analysis: to determine what information and processing services are required to support selected objectives and functions of an information system • Systems analysis involves: • Requirements determination/acquisition/capture • Requirements modelling/structuring/specification • Deliverable is the requirements specification

  3. Data gathering in systems development: systems analysis • Data gathering is a major task of systems analysis.Systems analysis involves: • Understanding and describing how the current system functions • Determining what users would like their new system to do (requirements) • Need to collect information: current and future situations, problems, opportunities, constraints

  4. Data gathering • What data? • Sources of data? • What data gathering methods? • What strategy for gathering data is needed? • How will the data gathered be analysed?

  5. What data to gather? • The business or organisation • The business environment • The system’s environment • The users of the system • The system: current and future • Constraints: e.g. cost, technical,

  6. What data to gather? • The business or organisation: • The nature of the business and its market and business environment • Business goals and objectives that drive what and how work is done • Organisational structure: major functions, departments etc • Major business subsystems and how they interact • Business policies and guidelines

  7. What data to gather? • Users of the system: • Roles and responsibilities • Reporting structures • Job specifications and actual tasks performed • Information needed to do their jobs • Formal and informal communication and workflow channels

  8. What data to gather? • The existing system: • Tasks and workflow: functions, processes, sequence of processes, methods and procedures, inputs, outputs • The data (definition, volumes, size etc.) • Interactions with other systems • Work volumes and processing cycles • Performance standards and criteria • Control mechanisms: e.g security, accuracy • Problems: e.g. efficiency, information

  9. What data to gather? • The new system: • System requirement: a need or desire to be met by a proposed system • Both functional requirements (processes and functionality) and • non-functional requirements (security, performance, service etc.) • Constraints e.g. existing technology • Interactions with other systems • Relationship to existing system

  10. Sources of data • Users and other stakeholders • Documents about the system • Documents about the organisation • Documents and data used within the existing system • Transactions within existing system • External sources

  11. Sources of data • Users • System sponsor/owner: overall project objectives • Managers: high level, broad view of existing system and requirements • End-users: detailed, operational level view of existing system and requirements • Technical staff: technology capaabilities, limitations etc. • External stakeholders: e.g. customers

  12. Sources of data • Documents about the system and organisation: • Organisation charts • Policy manuals • Business reports: financial, annual etc. • Jobs, procedure, operations manuals • Training manuals • Existing system documentation • Internal reports relating to the system

  13. Sources of data • Documents and data used within the existing system: • Files, databases, programs, forms, reports • Informal: Memos, bulletin boards, files • External sources: • Other organisations’ systems • Hardware & software vendors • Business & industry publications

  14. What data gathering methods? • Interviews • Questionnaires • Observation • Sampling documents and transactions • Research and site visits

  15. Interviews • Generally the most important and widely-used method for data gathering • May be formal/structured (specific questions) or informal/unstructured (general goal or purpose) • Need an interview strategy for the entire interviewing process • Need an interview plan or guide for each interview

  16. The interview strategy • Identify the users to interview: • Do this after you have an initial understanding of the organisation and system • Establish general objectives and guidelines for the entire interviewing process: • e.g. information to be obtained, sources, formats, documenting, analysis • Ensure all key people are included

  17. The interview strategy • Determine the sequence of interviews: • E.g. management first: • broad overview of system operations • gain support and co-operation • help to identify who to interview next • Then system users: • obtain information about detailed operations • Co-ordinate the interviewing process: • Compare results, select follow ups etc.

  18. The interview strategy • Need individual interview plans: • Initial interviews to meet users • Fact gathering interviews • Follow up interviews • Interview plans: • Decide on interview structure • Determine content of questions • Decide on question types

  19. Interviews • Need to consider: • Who has the information you need? • Where to conduct the interview? • When is the best time to interview? • How should the interview progress?

  20. The individual interview • Before the interview: • Arrange time and place, necessary materials, inform interviewee of interview purpose • Conduct the interview • After the interview: • Write an interview report • Review this with the interviewee at a follow up interview

  21. The interview structure • Preliminaries: • Introduction, purpose, environment and procedures e.g. permission to tape • “Body”: • Define what you already believe to be true and confirm this, explore points & issues further, new areas (questions) • Conclusion: • Summarise and confirm your findings • Schedule a follow up interview

  22. Interviews: types of questions • Closed: how many transactions per day? • Limits available responses • Open: tell me about ….. • Leaves options open for interviewee • Probe: tell me more about the problem with the …. • To clarify and expand • Mirror: From what you said, I understand that…. • To confirm what was said etc.

  23. Interviews: types of questions • Avoid long, complex, or double-barrelled questions: • what decisions are made during this process and how do you make them? • Avoid leading questions; • you don’t need the customer number on this report, do you? • Avoid loaded questions: • when did you first discover the mistake? • i.e. how long have you known and done nothing?

  24. Interviews: advantages • obtain extensive, complex detailed information • get insights and opinions • discover informal procedures • flexible e.g. explore issues further or new issues • establish rapport with interviewee and understand their attitudes • reveal the ‘politics’ of the system environment • information is revealed both by the spoken word and by the interviewee’s body language • guaranteed response

  25. Interviews: Disadvantages • Time-consuming • Costly • Danger of bias • More difficult to tabulate and analyse results e.g. to obtain an overall picture • Success in interviewing depends on the inter-personal skills of the interviewer

  26. Questionnaires • A structured method of data gathering in which written questions/comments are provided for the participants to respond to in written form • The questionnaire can take many forms - write comments/ select from a list of possible responses/ mark on a scale • May permit either quantitative or qualitative data (mark out of 10/grade from good to bad) • Usually involves no direct contact between data gatherer and respondents

  27. Questionnaires • Useful when small amounts of data are required from a large number of people • For geographically dispersed respondents • Types of questions: • Open-ended (free format) • Fill-in-the-blank • Multiple choice • Rating • Ranking

  28. Designing questionnaires • What facts and opinions to be collected • Who to sample and sample size • Types of questions and wording (precise, accurate, unambiguous) • How to administer e.g. paper, online, mail out etc. • Format and layout (grouping, crosschecks etc.) • Test on small sample of respondents • How completed questionnaires will be returned and collated • How analysis of the data will be carried out

  29. Questionnaires • Useful for: • Obtaining simple opinions, facts • Quantifying what was found in interviews • Identifying issues before interviewing • Determining extent of problems • Not useful for detailed or complex information or exploring issues in depth • Can supplement other methods

  30. Questionnaires: advantages • most economical method for gathering data from large numbers of people • quick and easy to administer • results can be tabulated rapidly and analysed readily • allow respondents to be anonymous • gives respondents time to reflect on answers • respondents complete in their own time

  31. Questionnaires: disadvantages • difficult to construct effective questionnaires • specific and limited amounts of information • possible low return rates • possible bias and misinterpretation • cannot probe issues further (inflexible) • cannot clarify vague or incomplete answers • lack non-verbal communication

  32. Observation • observing the actual processes of a system • need to prepare beforehand, and report on data collected • gain first hand knowledge of current system’s operations • clarify other information collected • understand complex procedures • inexpensive • behaviour distortions may affect reliability • unrepresentative samples affect reliability

  33. Sampling of documents and transactions • Sampling: collecting a representative sample of documents, forms, transactions • Useful for specific information e.g. transaction volumes and types, file sizes • Useful where large volumes exist • Information about existing system operations • Representative samples must be selected: determine sample size, appropriate range, avoid bias

  34. Research and site visits • Most problems not unique: learn from experiences of other organisations • Professional societies can provide contacts for site visits • Computer trade journals and magazines and the internet can be sources for research into the problem/s e.g. do appropriate software packages exist?

  35. Other data gathering methods Other “modern” methods used: • Discovery prototyping • JAD (Joint Application Development) sessions • Focus groups

  36. Discovery prototyping • Build a small-scale working model of the users’ requirements to discover or verify them • Develop the prototype quickly, get feedback from the users to add/change requirements • Useful for poorly understand parts/aspects of the system • Throw away prototypes: technology of prototype vs target technology platform • Prototyping is a process of discovery for users and developers

  37. Discovery prototyping • Advantages: • Improved understanding of new system • Better requirements definition • May speed up requirements process • Disadvantages: • Users may develop unrealistic expectations • Prototype may inhibit further exploration • Non-functional requirements often ignored

  38. JAD sessions • Often called JRP (Joint Requirements Planning) sessions when used for requirements • Highly structured group meeting held in special-purpose rooms involving system users, system owners and system developers who meet intensively for a period of time to analyse problems and define requirements • An effective JAD session requires extensive planning • selecting location, selecting participants, preparing an agenda

  39. JAD sessions: participants • Project sponsor or champion • top management with authority • full support for the project • encourages active participation • JAD leader/ facilitator • good communicator and negotiator • good business and organisational knowledge • impartial

  40. JAD sessions: participants • Business users and managers - clear understanding of the business • IS developers - not active participants, primarily there to learn • Scribe - takes notes, need to be published and disseminated quickly

  41. JAD sessions • actively involves users • improved consensus and resolution of conflicts/misunderstandings • reduces overall development time • is very expensive in • location costs • participants’ time

  42. Focus groups • an intensive group meeting held to get further information about a particular aspect of the business • sometimes used as a follow-up to other data gathering methods e.g. to explore issues in more detail • need a facilitator and appropriate users as participants

  43. A data gathering strategy • Data gathering must be carefully planned in order to make the most of the time and resources available: • Information sources • Data gathering methods • Recording and documentation methods • Data analysis methods • Procedures for reviewing results with management and users

  44. A data gathering strategy • E.g. a “top down” approach: • Initial interviews with management to determine major system activities and data • Document and verify this • Expand major system component descriptions into detailed descriptions: Interview operational users, sampling, questionnaires, observation etc • Document and verify this • Repeat these last two steps as necessary • Review findings with management

  45. A data gathering strategy • Consider costs: allow for time and resources required for initial and ongoing information gathering • Use the least expensive methods first • Plan how to check the validity of data: • Cross checking between groups, methods • Evaluate data for inconsistencies • Ask further questions • Plan documentation of data e.g. records of interviews etc. data dictionary, system models

  46. Data gathering in practice • Completeness? • Accuracy? • Objectivity? • Biases? • Stability? • Representative? • Finished?

  47. References • HOFFER, J.A., GEORGE, J.F. and VALACICH (2005) Modern Systems Analysis and Design, (4th edition), Pearson Education Inc., Upper Saddle River, New Jersey, USA. Chapters 5,6 • WHITTEN, J.L., BENTLEY, L.D. and DITTMAN, K.C. (2001) 5th ed., Systems Analysis and Design Methods, Irwin/McGraw-HilI, New York, NY. Chapter 6 • DWYER, J. (1997) The Business Communication Handbook (4th edition) Prentice-Hall, New York, N.Y. Chapter 5