1. Phase 2: Systems Analysis
Chapter 3
Requirements Modeling

2. Phase Description
Systems analysis is the second of five phases in the systems development life cycle (SDLC)
Uses requirements modeling and enterprise modeling to represent the new system
Before proceeding to the next phase, systems design, you will consider system development strategies

3. Systems Analysis Phase Overview
Uses models and other documentation tools to visualize and describe the proposed system
The deliverable is a system requirements document
Figure 3-2
Systems
Requirements
Document

4. Systems Analysis Phase Overview
Systems Analysis Skills
Analytical skills
Interpersonal skills
Team-Oriented Methods and Techniques
Joint application development (JAD)
Rapid application development (RAD)

5. Modeling Tools and Techniques
CASE Tools
Offer powerful modeling features
System analysts use modeling and fact-finding interactively
Functional Decomposition Diagrams
Functional decomposition diagram (FDD)
Figure 3-9

6. Modeling Tools and Techniques
Unified Modeling Language - Provides various graphical tools and techniques to represent the IS from user’s perspective
Use case diagrams
Figure 3-10
Figure 3-12

7. Modeling Tools and Techniques
Sequence diagrams
Shows timing of transactions between objects as they occur
Figure 3-13

8. System Requirements Checklist
System requirement – a feature that must be added to the IS to satisfy business requirements
Five general categories
Outputs
Inputs
Processes
Performance
Controls

9. System Requirements Checklist
Outputs
The Web site must report online volume statistics every four hours, and hourly during peak periods
The inventory system must produce a daily report showing the part number, description, quantity on hand, quantity allocated, quantity available, and unit cost of all parts — sorted by part number

10. System Requirements Checklist
Inputs
Manufacturing employees must swipe their ID cards into online data collection terminals that record labor costs and calculate production efficiency
The department head must enter overtime hours on a separate screen

11. System Requirements Checklist
Processes
The student records system must allow record access by either the student name or the student number
As the final step in year-end processing, the payroll system must update employee salaries, bonuses, and benefits and produce tax data required by the IRS

12. System Requirements Checklist
Performance
The system must support 25 users online simultaneously
Response time must not exceed four seconds

13. System Requirements Checklist
Controls
The system must provide log-on security at the operating system level and at the application level
An employee record must be added, changed, or deleted only by a member of the human resources department

14. Future Growth, Costs, and Benefits
Scalability
Determines how a system will determine future growth and demands.
To evaluate, you need information about projected future volume for all outputs, inputs, and processes

15. Future Growth, Costs, and Benefits
Total Cost of Ownership
Direct + indirect costs
especially important if the development team is evaluating several alternatives
Rapid Economic Justification (REJ)
Microsoft’s method for measuring TCO and benefits
Figure 3-14

16. Fact-Finding Overview Who, What, Where, When, How, and Why?
The first step is to identify the information you need
Start with a fact-finding plan
Who, What, Where, When, How, and Why?
Difference between asking what is being done and what could or should be done
Figure 3-15

17. Interviews
Systems analysts spend a great deal of time talking with people
Much of that time is spent conducting interviews

18. Interview Step 1: Determine the People to Interview
Informal structures
Step 2: Establish Objectives
Determine the general areas to be discussed
List the facts you want to gather
Figure 3-17

19. Interviews Step 3: Develop Interview Questions
Creating a standard list of interview questions helps to keep you on track and avoid unnecessary tangents
Avoid leading questions
Open-ended questions
Close-ended questions
Range-of-response questions

20. Interviews Step 4: Prepare for the Interview
Careful preparation is essential because an important meeting and not just a casual chat
Limit the interview to no more than one hour
Send a list of topics
Ask the interviewee to have samples available
Figure 3-18
Figure 3-19

21. Interviews Step 5: Conduct the Interview
Develop a specific plan for the meeting
Begin with good introduction
Use engaged listening
Allow the person enough time to think about the question
Summarize main points
After interview, summarize the session and seek a confirmation

22. Interviews Step 6: Document the Interview
During the interview, note taking should be kept to a minimum
After the interview, record the information quickly
After the interview, send memo expressing appreciation, including the main points discussed so the interviewee has a written summary and can offer additions or corrections

23. Interviews Step 7: Evaluate the Interview Unsuccessful Interviews
In addition to recording the facts obtained in an interview, try to identify any possible biases
Unsuccessful Interviews
No matter how well you prepare for interviews, some are not successful

24. Other Fact-Finding Techniques
Document Review
Observation
Seeing the system in action gives you additional perspective and a better understanding of the system procedures
Plan your observations in advance
Hawthorne Effect
Figure 3-20

25. Other Fact-Finding Techniques
Questionnaires and Surveys
When designing a questionnaire, the most important rule of all is to make sure that your questions collect the right data in a form that you can use to further your fact-finding
Fill-in form
Figure 3-21
Figure 3-22

26. Other Fact-Finding Techniques
Sampling
Systematic sample
Stratified sample
Random sample
Main objective of a sample is to ensure that it represents the overall population accurately

27. Other Fact-Finding Techniques
Research
Newsgroups
Site visit
Figure 3-23

28. Other Fact-Finding Techniques
Interviews versus Questionnaires
Interview is more familiar and personal
If you require detailed information from only a few people, then you probably should interview each person
When you seek input from a large group questionnaire is a very useful tool
Questionnaire gives many people the opportunity to provide input and suggestions

29. Documentation The Need for Recording the Facts
Record information as soon as you obtain it
Use the simplest recording method
Record your findings in such a way that they can be understood by someone else
Organize your documentation

30. Documentation Software Tools CASE Tools Word processing Spreadsheets
Histogram
Databases
Figure 3-24

31. Documentation Software Tools Presentation graphics
Personal information managers
Personal information manager (PIM)
Handheld computers
Personal digital assistants (PDAs)
Figure 3-25

32. Preview of Enterprise Modeling
At the conclusion of requirements modeling, systems developers should have clear understanding of business processes and system requirements
The next step is to model the logical design of the system

33. Test Yourself
Match the terms in the left column to the proper definitions in the right column.
1. Functional
decomposition
diagram
2. Use case
3. Sequence
Shows the timing of transactions between objects as they occur
b. Visual representation of the interaction between users and the information system
Top-down representation of business functions and processes 49

34. Test Yourself
Match the terms in the left column to the proper definitions in the right column.
1. Functional
decomposition
diagram
2. Use case
3. Sequence
Shows the timing of transactions between objects as they occur
b. Visual representation of the interaction between users and the information system
Top-down representation of business functions and processes 49

35. Test Yourself
The end product of the systems analysis phase is a system requirements document (T/F). 49

36. Test Yourself
The end product of the systems analysis phase is a system requirements document (T/F).
True 49

37. Test Yourself
Rapid application development (RAD) is a team-based technique that speeds up information systems development but doesn’t produce a functioning system like JAD does (T/F). 49

38. Test Yourself
Rapid application development (RAD) is a team-based technique that speeds up information systems development but doesn’t produce a functioning system like JAD does (T/F).
False 49

39. Test Yourself
Name two of the five general categories of system requirements: 49

40. Test Yourself
Name two of the five general categories of system requirements:
outputs
inputs
processes
performance
controls 49

41. Test Yourself
The fact-finding process includes interviewing, __________, observation, questionnaires, sampling, and _______. 49

42. Test Yourself
The fact-finding process includes interviewing, document review, observation, questionnaires, sampling, and research. 49

43. Test Yourself
What are the seven basic steps for interviewing? 49

44. Test Yourself What are the seven basic steps for interviewing?
Determine the people to interview
Establish objectives for the interview
Develop interview questions
Prepare for the interview
Conduct the interview
Document the interview
Evaluate the interview 49

45. Test Yourself
The following question is an example of an open-ended/closed-ended interview question:
“What added features would you like to have in the new system?” 49

46. Test Yourself
The following question is an example of an open-ended/closed-ended interview question:
“What added features would you like to have in the new system?” 49

47. Test Yourself
There are many other fact-finding techniques, in addition to interviewing. Name at least two others. 49

48. Test Yourself
There are many other fact-finding techniques, in addition to interviewing. Name at least two others.
Document review, observation, surveys and questionnaires, sampling, and research. 49

49. Test Yourself
What is sampling? If you have a list of customers, and want to methodically select every 10th customer for review, which sampling technique would you use? 49

50. Test Yourself
What is sampling? If you have a list of customers, and want to methodically select every 10th customer for review, which sampling technique would you use?
Sampling is a technique where the analyst collects examples of actual documents, records, logs, or forms.
A systemic sample would select every 10th customer. 49

51. Test Yourself
Name at least two guidelines for good documentation. 49

52. Test Yourself Name at least two guidelines for good documentation.
Write it down
Record information as soon as possible
Use the simplest recording method
Ensure that your work is understandable
Organize your documentation material 49

53. End Chapter 3