Chapter_3_ID2e_slides - Rose

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Chapter 3:
Understanding users
With a bit more added about personality theories!
Question 1
There’s lots to consider
• How the user interacts
– What can we predict, as we design
– Guidelines to ID success for types of users:
• Like new versus experienced
• Users from different cultures
• Different ages and interests
• The ID book focuses on this practical
side of “understanding users”
• Let’s look at that approach first…
What goes on in the mind?
Questions 2, 3
Core cognitive aspects
• Attention
• Perception and recognition
• Memory
• Reading, speaking and listening
• Problem-solving, planning, reasoning and decision-making,
learning
Question 4
Attention
• Selecting things to concentrate on at a point in time
from the mass of stimuli around us
• Involves audio and/or visual senses
• Information at the interface should be structured to
capture users’ attention, e.g. use perceptual boundaries
(windows), colour, reverse video, sound and flashing
lights
Activity: Find the price of a double room at the
Holiday Inn in Bradley
Activity: Find the price for a double room at the
Quality Inn in Columbia
Design implications for
attention
• Make information salient when it needs attending to
• Use techniques that make things stand out like colour,
ordering, spacing, underlining, sequencing and
animation
• Avoid cluttering the interface - follow the google.com
example of crisp, simple design
• Avoid using too much because the software allows it
Question 5
Perception and recognition
• How information is acquired from the world and
transformed into experiences
• Obvious implication is to design representations that are
readily perceivable, e.g.
– Text should be legible
– Icons should be easy to distinguish and read
– Use of white space is good
Is color contrast good? Find
italian
Are borders and white space
better? Find french
Which is easiest to read and
why?
What is the time?
What is the time?
What is the time?
What is the time?
What is the time?
Design implications
• Icons and other graphical representations should enable
users to readily distinguish their meaning
• Bordering and spacing are effective visual ways of
grouping information
• Sounds should be audible and distinguishable
• Speech output should enable users to distinguish
between the set of spoken words
• Text should be legible and distinguishable from the
background
Memory
• Involves first encoding and then retrieving knowledge
• We don’t remember everything - involves filtering and
processing what is attended to
• Well known fact that we recognize things much better than
being able to recall things
– Better at remembering images than words
– Why interfaces are largely visual
Context is important
• Context affects the extent to which information can be
subsequently retrieved
Recognition versus recall
• People are better at recognition than recall.
– If we listed here the stuff on the previous few slides, you’d
probably go, “Oh, yeah.”
– If we didn’t, how much could you recall?
The problem with the classic
‘72’
• George Miller’s theory of how much information people
can remember
• People’s immediate memory capacity is very limited
What some designers get up to…
•
•
•
•
•
Present only 7 options on a menu
Display only 7 icons on a tool bar
Have no more than 7 bullets in a list
Place only 7 items on a pull down menu
Place only 7 tabs on the top of a website page
– But this is wrong? Why?
Question 6
Personal information
management
• Personal information management (PIM) is a growing
problem for most users
Personal information
management
• Memory involves 2 processes
– recall-directed and recognition-based scanning
• File management systems should be designed to
optimize both kinds of memory processes
– e.g., Search box and history list
• Help users encode files in richer ways
– Provide them with ways of saving files using colour,
flagging, image, flexible text, time stamping, etc
Design implications
• Don’t overload users’ memories with complicated
procedures for carrying out tasks
• Design interfaces that promote recognition rather than
recall
Question 7
Learning
• Learning through doing
• Training wheels approach
Design Implications
• Must encourage exploration
• Constrain interfaces during learning
Left – a typical “expert
interface” that would lose
beginners in a hurry. This is
the 6-screen version of the
“Bloomberg Terminal” for
financial analysis.
Question 8
There’s lots to consider
• Back to understanding users in
general (slide 2):
– One could also role-in personas as a
way of designing for users.
• See “371_Week1Day04Interviewing.ppt”
• In general, perception, memory,
problem-solving, etc. are big
topics in psychology!
E.g. – User personality types
• Lots more than your scores on the
Myers-Briggs, but that’s a start:
– Attitudes: extraversion / introversion
– Functions: sensing / intuiting, and thinking
/ feeling
– Lifestyle: judging / perception
• Different “types” might interact
differently with your system.
 What’s the typical CS person, as a
Myers-Briggs type?
Personality theory – Different kinds
• Biological theories – Look at
people’s genetics, brain processes
• Behavioral theories – Look at
observable phenomena
– Don’t‘ try to infer internal processes
like “what they are thinking”
– B F Skinner may be the most famous
proponent
Personality theory – More!
• Psychodynamic theories – Freud,
etc.
– The unconscious mind and childhood
experiences influence what you are
aware of.
• Humanist theories – You shape
your own personality via free will.
– Carl Rogers and Abraham Maslow
Personality theory – Trait theories
• Like Myers-Briggs:
– People’s thinking has a stable set of
“traits” that differ from one person to
another.
– These traits cause them to behave in
certain ways
– The theorists don’t agree on how to
carve us up into these traits…
Personality theory – Another trait model
• E.g., here is Ned Herrmann’s “Whole brain
model’s” traits:
And here’s Ned
Personality theory & philosophy
• Like philosophers, personality theorists
all differ on questions like:
– Freedom vs determination
• Active vs reactive
• Person vs situation
– Heredity vs environment
– Uniqueness vs universality
– Optimistic vs pessimistic
• Freud, for one – very pessimistic
– Thought few people really “grow up”
– But he saw sick patients all day long!
Freud
Personality theory – Cognitive Psych
• A lot of ID people are “cognitive
psychologists:
– Try to build a model of mental processes in
the people interacting with something.
– In design, they often try to make
corresponding parts in the system:
• Like things to “help you remember”
• Things to “help you do problem solving”
• Cognitive psych tries to use
experiments to confirm its models
Personality theory – Cognitive Psych, cntd
• Major Topics in Cognitive Psychology
look like the ID book’s Ch 3 list:
–
–
–
–
–
–
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Perception
Language
Attention
Memory
Problem-Solving
Decision-Making and Judgment
Intelligence
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