1 / 36

Requirements Gathering

Requirements Gathering. 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?. Issues.

Télécharger la présentation

Requirements Gathering

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  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

More Related