1. Determining System
Requirements

2. SDLC
Project Identification
& Selection
Project Initiation
& Planning
Analysis
**
Logical Design
Physical Design
Implementation
Maintenance

3. Requirements Determination
 System requirements
 Functional requirements

Current and future functions

Current and future data

Current and future employee jobs

4. Requirements Structuring
 Two essential views of the current and
replacement information systems. Both are
describing the same system, but in a different
way.
 Process view: The sequence of data movement &
handling operations within the system

Data flow diagrams
 Data: The inherent structure of data independent of
how or when it is processed

Entity-relation diagrams

5. Remember to...

6. Who will you get info from?
 User Stakeholders
 Users
 Managers
 Client Stakeholders
 Technical Stakeholders

7. What Information Do You
Need?
 1.
 2.
 3.

8. Traditional Methods for
Determining System
Requirements
 Administering questionnaires
 Interviewing and listening
 Interviewing groups
 Directly observing users
 Analyzing procedures & other
documents

9. Administering Questionnaires
Advantages & Disadvantages
 Strengths
 1.
 2.
 3.
 Weaknesses
 1.
 2.
 3.

10. Give Me Ambiguity or Give Me
Something Else!
 How often do you back up your
computer files?
 A. Frequently
 B. Sometimes
 C. Hardly at all
 D. Never

11. This is better…
 How often do you back up the computer
files stored on the hard disk on the PC
you use for over 50% of your work
time?
 A. Frequently (at least once per week)
 B. Sometimes (from 1 to 3 times per
month)
 C. Hardly at all (once per month or less)
 D. Never

12. Interviewing & Listening
 Before
 During the interview
 Afterwards

13. During the Interview
 Beginning
 Introduction, open-ended questions, interest &
attention
 Middle
 Open & close-ended questions, f-u questions,
active listening, provide feedback, limit note-taking
 End
 Summarize, request feedback and/or f-u, ask for
corrections

14. Interviews
Advantages & Disadvantages
 Strengths
 Extracts both
qualitative and
quantitative data
 Detailed and
summary data
 Good way to find
needs and
assumptions
 Weaknesses
 Requires skills
 May be biased; May
collect lots of useless
data
 Expensive, time
consuming
 Requires other
methods to verify
results

17. How do you choose
interview questions?
 Open-ended questions
 1.
 2.
 3.
 Closed-ended questions
 1.
 2.
 3.

18. Find out about someone’s
job
 Write 3 open-ended
questions
 Ask 3 open-ended
questions (You may
substitute questions
during interview.)
 Write down answers
 Write 3 closed-ended
questions
 Ask 3 closed-ended
questions (You may
substitute questions
during interview.)
 Write down answers

19. Interviewing Groups
Adv & Disadv
 Strengths
 Not biased by one
user’s opinion
 Can get many user’s
opinion
 Weaknesses
 With many people
present, decision-
making takes time
 Interruptions during
process

20. You May Need to Analyze
Work Procedures
 Work procedures describe a particular
job or task
 May show duplication of effort
 May find missing steps
 May contradict info collected from
interviews, questionnaires, and
observations
 Formal systems vs informal systems

21. Directly Observing
Users
 Strengths
 Doesn’t rely on a
user’s memory
 More objective and
accurate than
interviews
 Weaknesses
 Hawthorne effect
 Time consuming

22. Temporary Job Assignment
 Strengths
 Good for learning
context, terminology,
procedures
 Provides insight for
other questions
 Get operation “feel”;
adds to analysts
credibility with users
 Weaknesses
 Time Consuming
 May bias future work
design towards way
things are currently
done

23. Reviewing internal documents
 Strengths
 Good way to learn
history and politics
 Explains current
context
 May help understand
why and way of
current procedures &
applications
 Weaknesses
 May bias future work
design
 Not useful for
obtaining current
attitudes or motives

24. Modern Methods for Determining
System Requirements
 Prototyping
 Joint Application Design (JAD) - Intensive
meetings between users, managers, sponsor,
& systems analysts to discuss & review
system requirements
 Group Support Systems (GSS) to share ideas
& voice opinions
 BPR – Business process reengineering
 CASE tools to analyze existing systems