Requirement Gathering
Fall 2006/1385
Semester 1
Sources
• Gather information on what system should
do from many sources
– Users
– Reports
– Forms
– Procedures
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Before you start gathering
requirements...
• Identify Stakeholders.
• Develop a problem statement
• Develop a “vision” - The project vision aligns
all project participants in a common and
clearly expressed direction. The vision
describes what the project is about and what
the product could ultimately become in a
perfect world. *
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What are some common software
requirements?
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Business rules - “Inventory shipments come on the 25th”
Budget - “We only have $1,000 for this project”
Interface - “We need a web enabled sales entry system”
Reports or outputs - “Stock check; monthly or weekly
summaries on ...”
Performance - “There might be 5000 concurrent users …”
Project Completion Date - “Oh, I need that next week …”
Security - “Everyone must have their own login and can see..”
Hardware - “We don’t want to buy additional hardware…14’’
screens will have to do.”
Software - “Everything must coded in Java and XML…”
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Requirements Continued...
• Error - Embedded system for the fire sprinklers;
financial.
• User level - “Mary has been dying to learn
Windows...”
• System maintenance - “Jack, our stock guy, he
can…”
• System location - “The server is located in Dallas and
we connect using this here modem. Just wiggle the
cord...”
• No subcontracting - “Due to confidentiality, we ask…”
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Requirements Gathering
Techniques
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Review Existing Documents.
Review current system input and outputs.
Interviews.
Role playing.
Research Existing Solutions.
Storyboarding.
Prototypes.
Questionnaires.
Brainstorming and idea reduction.
Workshop.
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Interviews
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Interviews
• At first you should try to find right people.
• This depends on what kind of information
you are looking for.
• Grouping interview:
– More effective use of time.
– Enables people to hear opinions of others and
to agree or disagree.
– Difficulty in scheduling
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Interviews -- Five Basic Steps
• Selecting interviewees
– Based on information needed
– Often good to get different perspectives
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Designing interview questions
Preparing for the interview
Conducting the interview
Post-interview follow-up
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Interview Questions
• Ask Open-Ended Questions.
– What do you think about the current system?
– What are some of the problems you face on a daily
basis?
• Avoid asking questions like:
– Why?
– For what?
• Do not phrase questions in ways that imply a
wrong or right answer
• Avoid asking people to describe things they
don’t usually describe.
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Interview Preparation Steps
• Prepare general interview plan
– List of question
– Anticipated answers and follow-ups
• Confirm areas of knowledge
• Set priorities in case of time shortage
• Prepare the interviewee
– Schedule
– Inform of reason for interview
– Inform of areas of discussion
• Sometimes it is better not to use tape recorder.
• You should know the domain and also the characteristics
of the interviewee.
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Conducting the Interview
• Appear professional and unbiased
• Record all information
• Check on organizational policy regarding tape
recording
• Be sure you understand all issues and terms
• Separate facts from opinions
• Give interviewee time to ask questions
• Be sure to thank the interviewee
• End on time
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Conducting the Interview
Practical Tips
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Don’t worry, be happy
Pay attention
Summarize key points
Be succinct
Be honest
Watch body language
Listen and Listen and Listen.
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Post-Interview Follow-Up
• Prepare interview notes
• Prepare interview report with in 48
hours.
• Look for gaps and new questions
• Send interviewee a report to confirm
the information.
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Questionnaires
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Questionnaires
• Good for large groups
• An average response level is usually around
10%, if there is no threat from the boss.
• When you used correctly, questionnaires can
be an excellent supplement to interviewing
data.
• A user can’t tip you off to explore different
problem areas with a questionnaire easily.
They will want to get through with it as soon
as possible, not to mention subjective
answers will usually be too brief.
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Good Questionnaire Design
• Begin with non-threatening and interesting questions
• Group items into logically coherent sections
• Do not put important items at the very end of the
questionnaire
• Do not crowd a page with too many items
• Avoid abbreviations
• Avoid biased or suggestive items or terms
• Number questions to avoid confusion
• Pretest the questionnaire to identify confusing questions
• Provide anonymity to respondents
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Storyboarding/Prototyping
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Storyboarding/Prototyping
• Passive storyboards - sketches, pictures, screenshots,
Powerpoint presentations, or sample outputs. Use stick
figures.
• Active storyboards - automated slide presentation or
movie describing the way the system behaves.
• Interactive storyboards - require participation by the
user. Throw away code. Sample interface or reporting
outputs; very close to a throwaway prototype.
• Storyboard elements:
– Who are the players
– What happens to them
– How it happens
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Storyboarding/Prototyping Continued...
• Don’t invest too much in the prototype. A throwaway prototype shouldn’t
take more than a week to build. Customers will be intimidated to make
changes if it looks to close to the real thing.
• If the prototype looks too good, customers will want it now or assume
that you are almost done. “So you are pretty much done, right?”
• Have backup plans. Bring a paper version of a interactive prototype.
– What prevents a client from taking your code and giving to another
developer? “Here is what we want and you can do this for a better price,
right?”
– Hardware presentation problems - no outlet, machine lockup, screen can’t
be seen by everyone, software not cooperating, etc.
– Make sure the prototype is portable.
• Sized to fit screen. Basic colors. Can it run without special software?
“Let me just load this calendar control…”
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