INTERACTION D ESIGN
1 Gathering Requirements: Acquisition Techniques O VERVIEW
Requirements Elicitation Techniques
What are requirements
What is involved in gathering them
2 W HAT REQUIREMENTS ARE
What users actually want.
Who the users are and what they can
Context of Use
Where, under what conditions,
environmental, organizational, cultural
or other the system shall operate. 3 U SER G OALS
Purchase A Computer On Line
Stay in Touch with Friends
Write an Assignment
Usability Goals that are critical
Learnability and Efficiency for a self-service airport check-in
Safety for a nuclear reactor
Exciting, engaging, challenging,etc..
Other Non-Functional Goals
Maintain Privacy, Maintain a Professional Image, Incr4ase
Availability to Colleagues etc. U SER C HARACTERISTICS AND SKILLS
Characteristics and Skills
ability, background and attitude to computers
Skill level: novice vs. expert
Frequency of use: casual vs. frequent
Concerns for each type of user:
Experts want flexibility and access/power.
Frequent users need short-cuts.
Novices and casual users want clear instructions.
5 U SER C HARACTERISTICS
• Characteristics and Skills:
• ability, background and attitude to computers
• System use: novice, expert, casual, frequent
• Novice: step-by-step (prompted), constrained,
• Expert: flexibility, access/power
• Frequent: short cuts
• Casual/infrequent: clear instructions, e.g. menu
6 C ONTEXT OF U SE
Limited Space? Noisy? Vibration? Light? Heat?
Sharing of files, displays, or paper
Style of work (collaborative vs. individual)
Hierarchy, communications structure and
infrastructure, relationship types (informal,
formal, mutual support, competition, trust),7power
relationships and politics. T HE R EQUIREMENTS A CQUISITION
Data Gathering Activities
Gathering information from the field/user
Data Analysis Activities
Making sense of the data
Requirements Modeling and Representation
Modeling and representing the results.
May occur at any point during the design process:
Initially when figuring out what the project is about.
During early prototyping i.e. when the first models of
the system are exposed to stakeholders 8
During later evaluation stages. D ATA G ATHERING A CTIVITIES
At the Beginning
Understanding Organization (or individual users or
user population) and current processes (or habits,
Understanding problem with existing situation and
implicit/explicit user needs and opportunities.
To test prototypes
To evaluate models and ideas
In the End
Final usability study
9 W HAT A RE THE S OURCES OF D ATA
User is a person who will actually use the interface.
Stakeholder is any person that is influenced by or
influences the system – may not be user. These include:
Secondary users: occasional users or those who use the
system through an intermediary.
Tertiary users: affected by the system or influence its
The social, cultural and physical environment in which the
users exist and work/live.
Existing forms, documents, rules/regulations.
That solve the same requirements
Competitors systems. 10 INTERVIEWS
Unstructured - are not directed by a
script. Rich but not replicable.
Structured - are tightly scripted, often like
a questionnaire. Replicable but may lack
Semi-structured - guided by a script but
interesting issues can be explored in more
depth. Can provide a good balance
between richness and replicability.
11 INTERVIEW PROCESS
Introduction – introduce yourself, explain the
goals of the interview, reassure about the ethical
issues, ask to record, present any informed
Warm-up – make first questions easy and non-
Main body – present questions in a logical order
A cool-off period – include a few easy questions to
defuse tension at the end
Closure – thank interviewee, signal the end,
e.g, switch recorder off. 12 INTERVIEW QUESTIONS
Closed questions: have a predetermined
answer format e.g. yes or no or choosing
from a list of options
Open-ended questions: do not have a
Closed-ended questions are easier to
analyse (e.g. aggregate)
13 C ONDUCTING THE INTERVIEW
Select the appropriate interviewee
Study related material
Build a list of questions!
Go in pairs or small groups!
Listen a lot, talk little.
Follow a master-apprentice model (see next).
Ask for details, or unknown terms, words and processes
that are mentioned.
Take thorough notes.
Review notes and write better or transfer to models.
Construct new set of clarification questions
Thank your interviewee. 14 R ELATIONSHIP M ODELS
Relationship model to aim for:
Analyst plays the role of the “apprentice” that wants
to learn a craft from the “master” (i.e. the
Relationship models to avoid
Analyst is able to enforce relationship
Can collect larger amounts of information
Can help gauge people’s real feelings needs etc.
Flexibility; can direct discussion so that the right
information is given
Can be hard to make sense of the result and compare
with other stakeholders.
It is expensive.
how do you tie the laces of your shoes?
knowledge the interviewee will not disclose (unconsciously or
Removal from context 16
Biases caused by interviewer’s attitude G ROUP E LICITATION (F OCUS G ROUP )
What is it:
Inquiry based on meeting of a group of individuals.
Has different dynamics than the interview.
Interviewer is basically a moderator of the group.
Less structured than interviews.
Why focus group?
Allow diverse or sensitive issues to be raised.
Provide direct evidence of similarities and differences
between participants (otherwise difficult to identify
thorough post-hoc analysis).
Participants play a more important role in guiding the
discussion = less control from the researcher = a bit more
Very efficient: e.g. two 8-person focus groups can produce
the same amount of information as 10 interviews. 17 W HAT GOES ON IN A F OCUS G ROUP
It consists of people who have a shared characteristic:
Sample from a particular market segment: e.g. young
adults living downtown Toronto (e.g. for a bike sharing
Sample from a group of users:
May involve many sessions with different samples.
Open ended exploratory questions
e.g. how do you feel about [such-and-such] process/system,
what are your priorities/strong desires etc.
Subject participants to stimuli and observe/solicit reaction
E.g. show them different wireframes (mock-ups) and gauge
their reaction (both verbal and non-verbal)
E.g. Ask them to classify, rate, priotitize, comment on concepts,
ideas, and early designs. Q UESTIONNAIRES
What they are:
Roughly: collections of questions answered by a
larger number of respondents.
Need a larger sample of the target population
Generation of statistics and performance of statistical
Impossible to access respondents otherwise (e.g.
Sample selection Method.
Questionnaire Administration. 19
Analysis of Responses. Q UESTIONNAIRE A DMINISTRATION
By Mail or E-mail
Send the questionnaire to a number of potential respondents
and wait for response.
Issue: response rate
Benefit: no individual biases.
Subject a group to the same stimuli.
All subjects answer under the same conditions.
Through Interview Schedules
Trained interviewers contact each respondent go through the
questions following a schedule.
Higher response rates.