3. Importance of Systems
Requirement
Systems Requirements is a feature that
must be included in order for the system
to be acceptable to users.
Two categories:
1) Functional requirements describe
activities or processes the system must
perform (e.g., calculate payroll taxes).
2) Technical requirements describe an
operating environment or performance
objective (e.g., must run with UNIX or
must have one-half second response
time).
3
4. Identify System Requirements
Systems Analysis Activities
◦ Requirements modeling has the
following categories:
Outputs
Inputs
Processes
Performance
Controls
4
5. System Requirements
Checklist
Outputs
Examples:
- 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 sorted by part
number
5
6. System Requirements
Checklist
Inputs
Examples:
- The department head must enter overtime
hours on a separate screen
- Student grades must be entered on
machine-scannable forms prepared by
the instructor.
- Each input form must include date, time,
product code, customer number, and
quantity 6
7. System Requirements
Checklist
Processes
Examples:
- The student records system must
calculate the GPA at the end of each
semester
- 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
7
9. System Requirements
Checklist
Controls
Examples:
- The system must provide logon 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 9
10. Future Growth, Costs, and
Benefits
Scalability
Why?:
◦ A scalable system offers a better return on
the initial investment
◦ To evaluate scalability, you need
information about projected future volume
for all outputs, inputs, and processes
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11. 11
In-Class Exercise
Study the DWC “Portal System” and give
one example to each of the following:
◦ Inputs
◦ Outputs
◦ Processes
◦ Performance
◦ Control
12. Fact-Finding
Fact-Finding Overview
◦ First, you must identify the information
you need
◦ Develop 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
12
13. Interviews
Step 1: Determine the People to
Interview
◦ Informal structures
Step 2: Establish Objectives for the
Interview
◦ Determine the general areas to be
discussed
◦ List the facts you want to gather
13
14. 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
◦ Closed-ended questions
◦ Range-of-response questions
14
15. Interviews
Step 4: Prepare for the Interview
◦ Careful preparation is essential because
an interview is an important meeting and
not just a casual chat
◦ Limit the interview to no more than one
hour
◦ Send a list of topics
Step 5: Conduct the Interview
◦ Develop a specific plan for the meeting
15
16. Interviews
• Step 6: Document the Interview
–Note taking should be kept to a minimum
–Note date, time, location, purpose of the
interview, and the main points you
discussed so the interviewee has a written
summary and can offer additions or
corrections
Step 7: Evaluate the Interview
◦ In addition to recording the facts obtained
in an interview, try to identify any possible
biases
16
17. Other Fact-Finding
Techniques
• Document Review
• Observation
– Seeing the system in
action gives you
additional
perspective and a
better understanding
of the system
procedures
17
18. 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
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19. 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
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20. Other Fact-Finding
Techniques
Research
◦ Can include the
Internet, IT
magazines, and books
to obtain background
information, technical
material, and news
about industry trends
and developments
◦ Site visit
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21. Other Fact-Finding
Techniques
Interviews versus Questionnaires
◦ Interview is more familiar and personal
◦ Questionnaire gives many people the
opportunity to provide input and
suggestions
◦ Brainstorming
21
22. Review Questions:
What are the five questions typically used in
fact-finding? What additional question can
be asked during this process? refer to (Page 157)
What is a systems requirement, and how
are systems requirements classified? refer to
(Page 153)
What are three types of sampling, and why
would you use them? refer to (Page 167-168)
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Editor's Notes
Outputs: Refer to electronic or printed information produced by the system (Ch.4 - page 142)
Inputs: Refer to necessary data that enters the system, either manually or in an automated manner (Ch.4 - page 142)
Processes: Refer to logical rules that are applied to transform the data into meaningful information.(Ch.4 - page 142)
Performatnce: Refer to system characteristics such as speed, volume, capacity, availability, and reliability. (Ch.4 – p 142)
Scalability: Refer to system availability to handle increased business volume and transactions in the future. Because it will have a longer useful life. (Ch.4 - page 155)
Leading questions that suggest or favor a particular reply. For example, rather than asking, “What advantages do you see in the proposed system?” you might ask, “Do you see any advantages in the proposed system?”OPEN-ENDED QUESTIONS encourage spontaneous and unstructured responses. Such questions are useful when you want to understand a larger process or draw out the interviewee’s opinions, attitudes, or suggestions. Hereare some examples of open-ended questions: What are users saying about the newsystem? How is this task performed? Why do you perform the task that way? Howare the checks reconciled? CLOSED-ENDED QUESTIONS: limit or restrict the response. You use closed-ended questions when you want information that is more specific or when you need to verify facts. Examples of closed-ended questions include the following:How many personal computers do you have in this department? Do you review the reports before they are sent out? How many hours of training does a clerk receive? How many customers ordered products from the Web site last month?RANGE-OF-RESPONSE QUESTIONS are closed-ended questions that ask the person to evaluate something by providing limited answers to specific responses or on a numeric scale. This method makes it easier to tabulate the answers and interpret the results. Range-of-response questions might include these: On a scale of 1 to 10, with 1 the lowest and 10 the highest, how effective was your training? How would you rate the severity of the problem: low, medium,or high? Is the system shutdown something that occurs never, sometimes, often, usually, or always?(Ch4. Pg. 160)
A questionnaire, also called a survey, is a document containing a number of standard questions that can be sent to many individuals. Questionnaires can be used to obtain information about a wide range of topics,including workloads, reports received, volumes of transactions handled, job duties,difficulties, and opinions of how the job could be performed better or more efficiently
(Ch4 – Pg. 167)Suppose you have a list of 200 customers who complained about errors in their statements,and you want to review a representative sample of 20 customers. Systematic sample would select every tenth customer for review. If you want to ensure that the sampleStratified sample ensures sample is balanced geographically, to select five customers from each of four zip codes. Another example of stratified sampling is to select a certain percentage of transactions from each zip code, rather than a fixed number.Random sample selects any 20 customers.
brainstorming, which refers to a small group discussion of a specific problem, opportunity, or issue. This techniqueencourages new ideas, allows team participation, and enables participants to build on each other’s inputs and thoughts
