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4 Systems Analysis and Design in a Changing World, Fourth Edition.

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Presentation on theme: "4 Systems Analysis and Design in a Changing World, Fourth Edition."— Presentation transcript:

1 4 Systems Analysis and Design in a Changing World, Fourth Edition

2 4 2 Learning Objectives u Describe the activities of the systems analysis life cycle phase u Explain the effect of business process reengineering on activities of the analysis phase u Describe the difference between functional and nonfunctional system requirements u Describe the kind of information that is required to develop system requirements u Determine system requirements through review of documentation, interviews, observation, prototypes, questionnaires, vendor research, and joint application design sessions u Discuss the need for validation of system requirements to ensure accuracy and completeness and the use of a structured walkthrough

3 4 3 The Analysis Phase in More Detail u Gather information u Define system requirements l Functional and nonfunctional u Prioritize requirements u Prototype for feasibility and discovery u Generate and evaluate alternatives u Review recommendations with management

4 4 4 Activities of the Analysis Phase and Their Key Questions

5 4 5 Stakeholders—The Source of System Requirements u People with interest in successful system implementation u Three primary groups of stakeholders l Users (use system) l Clients (pay for and own system) l Technical staff (ensure system operation) u Every type of stakeholder is identified by analyst

6 4 6 More On Users as Stakeholders u Horizontal user roles – information flow across departments u Vertical user roles – information needs of clerical staff, middle management, and senior executives l Business users perform day-to-day operations l Information users need current information l Management users need summary information l Executive users need strategic information l External users may have access to system

7 4 7 Techniques for Information Gathering u Analysis phase done to understand business functions and develop system requirements u Original structured approach l Create model of existing system l Derive requirements from existing system model u Current approach l Identify logical requirements for new system l Balance the review of current business functions with new system requirements

8 4 8 Relationship Between Information Gathering and Model Building

9 4 9 Themes for Information-Gathering Questions

10 4 10 Characteristics for Successful Requirements Determination u Question everything u Be impartial u Assume anything is possible u Pay attention to details u Reframe

11 4 11 Sampling Sampling is the process of systematically selecting representative elements of a population. We use sampling to make assumptions of the population as a whole. We sample to: l Contain costs l Speed up data gathering l Improve effectiveness l Reduce bias

12 4 12 Sampling Design To design a good sample, analysts need to: u Determine the data to be collected u Determine the population to be sampled u Choose the type of sample u Decide on the sample size (not covered)

13 4 13 Fact-Finding Methods u Review existing reports, forms, and procedure descriptions u Interview and discuss processes with users u Observe and document business processes u Build prototypes u Distribute and collect questionnaires u Conduct joint application design (JAD) sessions u Research vendor solutions

14 4 14 Review Existing Reports, Forms, and Procedure Descriptions u Source: External industry-wide professional organizations and trade publications u Source: Existing business documents and procedure descriptions within organization l Identify business rules, discrepancies, and redundancies l Be cautious of outdated material l Obtain preliminary understanding of processes l Use as guidelines/visual cues to guide interviews

15 4 15 Conduct Interviews and Discussions with Users u Effective way to understand business functions and rules u Time consuming and resource expensive u May require multiple sessions to l Meet all users l Understand all processing requirements u Can meet with individuals or groups of users u List of detailed questions prepared

16 4 16 Sample Checklist to Prepare for User Interviews

17 4 17 Interviewing u Planning the Interview u Conducting the Interview u Writing the Interview Report u Join Application Design (JAD)

18 4 18 Question Types – Open-Ended Questions Benefits u Interviewee at ease u Use interviewee vocabulary u Detail u Generate new questions u More interesting for interviewee u More spontaneity u Phrasing is easier for interviewee u Could use them when not prepared Drawbacks u May result in too much detail u Possibly lose control of interview u Response may take too much time u Appear unprepared u Appear that objectives are lacking

19 4 19 Question Types – Closed-Ended Questions Benefits u Save time u Easy to compare interviews u Getting to the point u Control over interview u Cover lots of ground u Getting only relevant data Drawbacks u Boring to interviewee u Lack of detail u Miss main ideas u Fail to build rapport with interviewee

20 4 20 Question Types – Probes u Follow-up question u Used to get more meaning out of an answer u Can be either open or closed-ended questions u Indicates that you are listening

21 4 21 Question Pitfalls u Avoid leading questions u Avoid double-barreled questions u Avoid ambiguity, especially in closed-ended questions u Pretest questions before use

22 4 22 Arranging Questions u Pyramid Structure l Open with a specific question and close with a general one l Used to warm up the interviewee l Used for reluctant interviewees u Funnel Structure l Open with a general question and close with a specific one l Easy, non-threatening way to start interview l Used when interviewee feels emotional about the topic u Diamond-shaped Structure l Uses a combination of the two approaches above l Combines strengths of two approaches l Takes longer l Keeps interviewee’s interest by using a variety of questions

23 4 23 Making a Record of the Interview Making an Audio Recording u Provides accurate record u You can listen and respond more rapidly u Allows better eye contact u Allows replay u Can make interviewee nervous u Difficult to locate messages on long tapes u Cost (need to transcribe tapes) Note taking u Keep the interviewer alert u Show interest in interview u Demonstrates prepareness u Lose vital eye contact u Interviewee stops when notes are taken u Cause attention to facts and little attention to feelings and opinions

24 4 24 Conducting the Interview (my suggestions) u Arrive early u Shake hands u Inform interviewee how you will work (note taking, recorder) u Check equipment u Start with open-ended questions to warm-up interview and get a feeling of attitudes u Cover all questions in 45 min to 1 hour interview u Reflect back to the interview u Ask if something was not covered u Summarize and give feedback

25 4 25 Writing the Interview Report u Write a report as soon as possibly after the interview u Note the main points of the interview and your own opinions u Review the report with the respondent at a follow- up meeting

26 4 26 System Requirements u New system capabilities and constraints u Functional requirements l Activities system must perform (use cases) l Based on procedures and business functions l Documented in analysis models u Nonfunctional requirements l Technical environment or performance objectives l Usability, reliability, and security requirements

27 4 27 Distribute and Collect Questionnaires u Limited and specific information from a large number of stakeholders u Preliminary insight into business u Not well suited for gathering detailed information u Closed-ended questions direct person answering question u Open-ended questions encourage discussion and elaboration

28 4 28 Conduct Joint Application Design Sessions u Expedites investigation of system requirements u Seeks to compress fact-finding, modeling, policy formation, and verification activities into shorter time frame u Critical factor is to have all important stakeholders present

29 4 29 Joint Application Design Participants u Session leader trained in group dynamics and JAD group facilitation u Knowledgeable business and system users and policy makers u Technical staff representatives to handle l Computer and network configurations l Operating environments l Security issues u Project team members

30 4 30 Joint Application Design Facilities u Conducted in special room l Limit interruptions l May be off-site u Resources l Overhead projector, white board, flip charts, work material l Electronic support (laptops) l CASE tools l Group support systems (GSS)

31 4 31 A JAD Facility (Figure 4-16)

32 4 32 What Is Prototyping? u A repetitive process in which analysts and users build a rudimentary version of an information system based on user feedback u Prototyping is good when: l Users are unclear about their requirements. l The system affects a relatively small number of users. l Designs are complex. l Communication between users and analysts needs to be strengthened. l Rapid application development tools are available.

33 4 33 Build Prototypes u Preliminary working model of a larger, more complex system component l Discovery, design, evolving prototypes u Prototype should be l Operative u Working model to provide “look and feel” l Focused to accomplish single objective l Quick u Built and modified rapidly with CASE tools

34 4 34 Validating the Requirements u Make sure gathered information is correct u Structured walkthrough l Effective means of implementing quality control early in project l Verify and validate system requirements l Review of findings from investigation and of models based on findings u Project manager responsible for system quality l Systems analyst, project manager are partners

35 4 35 Summary u Analysis phase activities l Gather information l Define system requirements l Prioritize requirements l Prototype for feasibility and discovery l Generate and evaluate alternatives l Review recommendations with management u Gathering system requirements l Functional and nonfunctional l Work with various stakeholders (users, clients, technical staff) u What kind of information do I need? l What are the business processes and operations? l How are the business processes performed? l What are the information requirements? u Primary information-gathering techniques l Review existing reports, forms, and procedure descriptions l Conduct interviews and discussions with users l Observe and document business processes l Build prototype working models l Distribute and collect questionnaires l Conduct JAD sessions l Research vendor solutions


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