User Modelling
ID 405 Human-Computer Interaction
Ascending and Descending By M. C. Escher 1960
Mental models and program/design models
Users’ mental
model
Designers’ program
model
What you are up against…
- a mental model is what the user believes about the
system at hand (belief, and not facts)
- individual users each have their own mental model
(different users, different models)
- mental models are in a flux (users are bound to update
models with experience)
- users suffer model inertia*
- mental models are simple (if design model is nontrivial, it's
probably not the user model)*
Let’s see some examples…
- the word "Google" is usually the top query at other search
engines, and words like "Yahoo" and "Bing" score high on
Google
- Why do people search for a website if they already know
its name? Why not just type, google.com into the URL
field?
Let’s see some examples…
Users don't just confuse search fields; many less tech-savvy
users don't understand the differences between many other
common features:
•Operating-system windows vs. browser windows
•A window vs. an application
•Icons vs. applications
•Collapsible/expandable views
•Single-clicks vs. double-clicks
•Local vs. remote info
•…
Let’s see some examples…
- Netflix queue vs. shopping cart
- Picture embedding in a word processor vs. WYSWYG
HTML editor
Let’s see some examples…
- When people have to guess how a program is going to
work, they tend to guess simple things, rather than
complicated things
Let’s see some examples…
- When people have to guess how a program is going to
work, they tend to guess simple things, rather than
complicated things
Let’s see some examples…
- In Microsoft Windows the Alt+Tab key combination
switches to the "next" window
- Most users would probably assume that it simply rotates
among all available windows
- If you have window A, B, and C, with A active, Alt+Tab
should take you to B. Alt+Tab again would take you to C
- Actually, what happens is that the second Alt+Tab takes
you back to A. The only way to get to C is to hold down Alt
and press Tab twice.
- It's a nice way to toggle between two applications, but
almost nobody figures it out, because it's a slightly more
complicated model than the rotate-among-availablewindows model
So what can we do?
In case of a mental model mismatch, you basically have two
options:
- Make the system conform to users' mental models
- Improve users' mental models so that they more
accurately reflect the system
Personas
- Personas are archetypes that describe various goals and
observed behaviour patterns among your potential users
and customers
- A persona encapsulates and explains the most critical
behavioural data in a way that designers and stakeholders
can understand, remember and relate to
- Personas use storytelling to engage the social and
emotional aspects of our brain, which helps us to visualise
and empathise with the user in a vivid and direct manner
Personas
Katie Bennet, digital camera user
from Designing for the Digital Age: Creating Human-Centred Products
and services by By Kim Goodwin (pp.230)
-Set of goals
-Mental model
-Environment
-Skills
-Frustrations
-Likes & dislikes
-Attitudes
-Typical tasks
-Behaviour patterns
-…
What personas are
- Personas are fictional characters but distilled from real
data you gathered from actual users (data driven & not
based on assumptions)
- They are based on what users do and why they do them
(actions, goals, motivations & behaviours)
- Sound personas emerge from good data, rigorous
analysis, and compelling human presentation
What personas are NOT
- Creative writing exercises with photos and fictitious
biographical details
- Market segments
Market
segments
- averages
Segment
size and
value
Skills
Demographics attitudes and
behaviours
always have
May have
Personas
Mental
models
and goals
What personas are NOT
- Creative writing exercises with photos and fictitious
biographical details
- Market segments
Market
segments
- averages
Segment
size and
value
Skills
Demographics attitudes and
behaviours
always have
May have
Personas
Mental
models
and goals
Structure of a persona
1. Use a photo for your persona. A good photo is key to
making the persona believable and convincing.
Structure of a persona
2. Give your personas names. Refer to them by those
names. Avoid silly or alliterative names. Also avoid
placing your persona in a category (like “Stay-at-homeMom”). Silly names and categories allow people to
stereotype the persona, and thus treat them as an other,
not as someone potentially just like themselves.
Structure of a persona
3. Highlight personas key behaviors and motivations. In
order to deliver a great user experience, you need to
understand why people would engage with that
experience, and how they would go about it.
Structure of a persona
4. Include basic demographic information. But only to the
degree that helps a reader better understand who your
persona is. Age, income, occupation, marital status can be
informative.
Structure of a persona
5. Provide key statements in the persona’s voice. This
statement might be something you heard in a research
interview, or it might be a fabrication. The quote will allow
others to see a distinct person.
Summary
- User research is primarily about empathy — getting
designers and developers to have empathy for their users,
and be able to deliver products and services that really
appreciate the users’ needs and goals
- And personas are perhaps the best tool in the usercentered design toolbox for communicating empathy —
they feel like real people with real concerns, and when
crafted well, can transfer insights realized through
research to other members of the project team
Summary
- User research is primarily about empathy — getting
designers and developers to have empathy for their users,
and be able to deliver products and services that really
appreciate the users’ needs and goals
- Personas are perhaps the best tool in the user-centered
design toolbox for communicating empathy — they feel
like real people with real concerns, and when crafted well,
can transfer insights realized through research to other
members of the project team