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Requirements Gathering

Requirements Gathering

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Requirements Gathering

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  1. Requirements Gathering

  2. Contemplative Questions • What techniques are available for gathering information about requirements? • Which technique is best? When is each appropriate to use? • What are the problems of bias? From where can bias come?

  3. Issues • What are all the sources of information available? • What is the goal? What is the end result of gathering information about requirements?

  4. Sources • Users • Reports • Forms • Procedures Is it “better” to utilize more than one of the above? How do we define “better”? What is the inherent tradeoff here?

  5. What characteristics should analysts possess? • Impertinence • Question everything • Impartiality • Find the best organizational solution • Relaxation of constraints • Attention to detail • Reframing • View the organization in new ways Are these attributes important? Why or why not? What do analysts really do?

  6. 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 In and of themselves, these deliverables are not important. What do they become? What is the bigger picture here?

  7. Techniques • Interviews • Questionnaires • Observation • Document / Procedure Analysis • JAD • Prototyping

  8. Exercise • Rate each of the previous techniques based on these criteria (high, medium or low): • Degree of participation with user • Information "richness" (depth) • Breadth of information (scope) • Cost (Analysts' Time) • Cost (Users’ Time) • Ability to integrate information • User involvement w/ system design

  9. Interviews -- Five Basic Steps • Selecting Interviewees • Designing the Interview Guide • Preparing for the Interview • Conducting the Interview • Post-Interview Follow-up Each of these steps is ripe with opportunities for injecting bias. Is bias a bad thing? Why or why not? Which step takes the longest?

  10. Interviews • Selecting Interviewees • Same guidelines as questionnaires • Should be representative of all users • Recall the effects of bias • Types of samples • Convenient • Random sample • Purposeful sample • Stratified sample

  11. Interviews • Designing the Interview Guide Sample Interview Guide Figure 7-2 For whose benefit are interview guides? Is it worthwhile to construct them? What are the benefits? What about bias?

  12. Interviews • Designing the Interview Guide • Overall Questioning Strategies • General area, narrowing to specific topic (preferred) • Tell me about CTI site, then Courses, then Course Information, then enrollment numbers • Specific topic, moving to General • Enrollment numbers on Course Info page to CTI site in general • Types of Interview Questions • Open-Ended • No pre-specified answers • Close-Ended • Respondent is asked to choose from a set of specified responses

  13. Interviews • Preparing for the Interview • Confirm place/time • Review areas to be covered • Encourage interviewee to bring reference materials

  14. Interviews • Conducting the Interview • Gather facts, opinions and speculations • Avoid bias when phrasing questions, e.g. phrasing in ways that imply a wrong or right answer • Never take sides on an issue • Tape record with individual and organizational permission

  15. Interviews • Conducting the Interview • Assume tape recording will not work, which means you must simultaneously • Follow the interview guide, and • Listen very carefully to what is being said, and • Observe body language and emotions, and • Separate facts from opinions, and • Take notes, and • Plan the next question/flow of the interview • THIS IS VERY DIFFICULT TO DO CORRECTLY AND MUST BE PRACTICED.

  16. Interviews • Conducting the Interview--practical tips • Don’t worry, be happy • Pay attention • Summarize key points • Be succinct and honest • Give interviewee time to ask questions • Be sure to thank the interviewee • End on time • And, don’t ask unnecessary questions!

  17. Interviews • Post Interview • Consider asking for more time if necessary • Confirm major points identified with interviewee • Look for Gaps and New Questions • “If it isn’t in the field notes, it never happened.” • Type up notes within 24 hours (preferably immediately after the interview is over

  18. 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

  19. Questionnaires • A questionnaire is similar to a very structured interview • Many of the same guidelines apply • Choosing respondents • Should be representative of all users • Same types of samples • Convenient • Random sample • Purposeful sample • Stratified sample

  20. Questionnaires Response rates to questionnaires are commonly low— over 15% is sometimes considered very good.

  21. Observation • Directly Observing Users • Serves as a good method to supplement interviews • Often difficult to obtain unbiased data • People often work differently when being observed • Be cognizant of normal and abnormal conditions, e.g. entering an order vs. the end of quarter sales report

  22. Document/Procedure Analysis • Great starting point • Gets analyst quickly up to speed with user jargon • Can create preliminary models, e.g. DFDs or ERDs • 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

  23. Document/Procedure Analysis • 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

  24. Joint Application Design • Joint Application Design (JAD) • Brings together key users, managers and systems analysts • Purpose: collect system requirements simultaneously from key people • Conducted off-site

  25. Joint Application Design

  26. Joint Application Design • Participants • Session Leader • Users • Managers • Sponsor • Systems Analysts • Scribe • IS Staff

  27. Joint Application Design • 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

  28. Joint Application Design • End Result • Documentation detailing existing system • Consensus on 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 What is the apparent drawback with JAD?

  29. Prototyping • Repetitive process • Rudimentary version of system is built • Replaces or augments SDLC • Goal: to develop concrete specifications for ultimate system

  30. 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 • Is prototyping useful in any of these cases? • 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

  31. 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

  32. Business Process Reengineering (BPR) • Changes to the underlying Business Process (BP) can vary from project to project • Minor changes to process (BP Automation) • Moderate changes (BP Improvement) • Major (BP Reengineering) • BPR is the search for and implementation of radical change in business processes to achieve breakthrough improvements in products and services • Some common BPR Goals • Reorganize complete flow of data in major sections of an organization • Eliminate unnecessary steps completely • Combine steps, or • Become more responsive to future change

  33. Business Process Reengineering (BPR) • 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

  34. 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

  35. Business Process Reengineering (BPR)

  36. Summary • There are many techniques for gathering information about functional requirements • To minimize bias it is a good idea to use more than one technique • Consider the pros and cons of each • Theoretically you should gather information until saturation, i.e. you learn nothing new