Chapter07 determining system requirements
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This document discusses various methods for determining system requirements, including interviews, questionnaires, observation, document analysis, Joint Application Design (JAD), prototyping, and business process reengineering (BPR). Interviews can use open-ended or close-ended questions, and preparation is important. Questionnaires must be carefully designed and can include both open-ended and close-ended questions. JAD brings together key stakeholders to simultaneously collect requirements. Prototyping converts early requirements into a working system for user feedback. BPR aims to radically improve processes through reorganization and leveraging disruptive technologies.
Chapter07 determining system requirements
- 1. Copyright 2002 Prentice-Hall, Inc. Modern Systems Analysis and Design Third Edition Jeffrey A. Hoffer Joey F. George Joseph S. Valacich Chapter 7 Determining System Requirements 7.1
- 2. Learning Objectives Describe options for designing and conducting interviews and develop a plan for conducting an interview to determine system requirements Design, distribute, and analyze questionnaires to determine system requirements Explain advantages and pitfalls of observing workers and analyzing business documents to determine requirements 7.2
- 3. Learning Objectives Explain how computing can provide support for requirements determination Learn about Joint Application Design (JAD) Use prototyping during requirements determination Select the appropriate methods to elicit system requirements Apply requirements determination to Internet applications 7.3
- 4. Performing Requirements Determination Gather information on what system should do from many sources Users Reports Forms Procedures 7.4
- 5. Performing Requirements Determination Characteristics for gathering requirements Impertinence Question everything Impartiality Find the best organizational solution Relaxation of constraints Attention to detail Reframing View the organization in new ways 7.5
- 6. Deliverables and Outcomes Types of deliverables: Information collected from users Existing documents and files Computer-based information Understanding of organizational components Business objective Information needs Rules of data processing Key events 7.6
- 7. Traditional Methods for Determining Requirements Interviewing and Listening Gather facts, opinions and speculations Observe body language and emotions Guidelines Plan Checklist Appointment Be neutral Listen Seek a diverse view 7.7
- 8. Traditional Methods for Determining Requirements Interviewing (Continued) Interview Questions Open-Ended No pre-specified answers Close-Ended Respondent is asked to choose from a set of specified responses Additional Guidelines Do not phrase questions in ways that imply a wrong or right answer Listen very carefully to what is being said Type up notes within 48 hours Do not set expectations about the new system 7.8
- 9. Traditional Methods for Determining Requirements Administering Questionnaires More cost-effective than interviews Choosing respondents Should be representative of all users Types of samples Convenient Random sample Purposeful sample Stratified sample 7.9
- 10. Traditional Methods for Determining Requirements Questionnaires Design Mostly closed-ended questions Can be administered over the phone or in person Vs. Interviews Interviews cost more but yield more information Questionnaires are more cost-effective See table 7-4 for a complete comparison 7.10
- 11. Traditional Methods for Determining Requirements Interviewing Groups Advantages More effective use of time Enables people to hear opinions of others and to agree or disagree Disadvantages Difficulty in scheduling Nominal Group Technique Facilitated process to support idea generation by groups Individuals work alone to generate ideas which are pooled under guidance of a trained facilitator 7.11
- 12. Traditional Methods for Determining Requirements Directly Observing Users Serves as a good method to supplement interviews Often difficult to obtain unbiased data People often work differently when being observed 7.12
- 13. Analyzing Procedures and Other Documents Types of information to be discovered: Problems with existing system Opportunity to meet new need Organizational direction Names of key individuals Values of organization Special information processing circumstances Reasons for current system design Rules for processing data 7.13
- 14. Analyzing Procedures and Other Documents Four types of useful documents Written work procedures Describes how a job is performed Includes data and information used and created in the process of performing the job or task Business form Explicitly indicate data flow in or out of a system Report Enables the analyst to work backwards from the report to the data that generated it Description of current information system 7.14
- 15. Modern Methods for Determining Requirements Joint Application Design (JAD) Brings together key users, managers and systems analysts Purpose: collect system requirements simultaneously from key people Conducted off-site Prototyping Repetitive process Rudimentary version of system is built Replaces or augments SDLC Goal: to develop concrete specifications for ultimate system4.15
- 16. Joint Application Design (JAD) Participants Session Leader Users Managers Sponsor Systems Analysts Scribe IS Staff 4.16
- 17. Joint Application Design (JAD) End Result Documentation detailing existing system Features of proposed system CASE Tools During JAD Upper CASE tools are used Enables analysts to enter system models directly into CASE during the JAD session Screen designs and prototyping can be done during JAD and shown to users 4.17
- 18. Joint Application Design (JAD) Supporting JAD with GSS Group support systems (GSS) can be used to enable more participation by group members in JAD Members type their answers into the computer All members of the group see what other members have been typing 7.18
- 19. Prototyping Quickly converts requirements to working version of system Once the user sees requirements converted to system, will ask for modifications or will generate additional requests Most useful when: User requests are not clear Few users are involved in the system Designs are complex and require concrete form History of communication problems between analysts and users Tools are readily available to build prototype 7.19
- 20. Prototyping Drawbacks Tendency to avoid formal documentation Difficult to adapt to more general user audience Sharing data with other systems is often not considered Systems Development Life Cycle (SDLC) checks are often bypassed 7.20
- 21. Business Process Reengineering (BPR) Search for and implementation of radical change in business processes to achieve breakthrough improvements in products and services Goals Reorganize complete flow of data in major sections of an organization Eliminate unnecessary steps 7.21
- 22. Business Process Reengineering (BPR) Goals (Continued) Combine steps Become more responsive to future change Identification of processes to reengineer Key business processes Set of activities designed to produce specific output for a particular customer or market Focused on customers and outcome Same techniques are used as were used for requirements determination 7.22
- 23. Business Process Reengineering (BPR) Identify specific activities that can be improved through BPR Disruptive technologies Technologies that enable the breaking of long-held business rules that inhibit organizations from making radical business changes See table 7-7 7.23
- 24. Summary Interviews Open-ended and close-ended questions Preparation is key Questionnaires Must be carefully designed Can contain close-ended as well as open- ended questions 7.24
- 25. Summary Other means of gather requirements Observing workers Analyzing business documents Joint Application Design (JAD) Prototyping Business Process Reengineering (BPR) Disruptive technologies 7.25