Presented at 4th UX Conference at Shiraz - December 2019

1. ،‫مردم‬‫دیزاینی‬‫را‬ ‫آنها‬ ‫که‬
‫بگیرد‬ ‫نادیده‬
‫گرفت‬ ‫خواهند‬ ‫نادیده‬
‫بهشتی‬ ‫دانشگاه‬ ‫مغز‬ ‫و‬ ‫شناختی‬ ‫علوم‬ ‫پژوهشکده‬
‫حــ‬‫امد‬‫عبـدی‬
‫پژوهشگر‬‫علوم‬‫شناختی‬(‫مدلسـازی‬‫محاسبا‬‫تی‬)
@hamedabdi/hamedabdi

2. “
“People ignore design that ignores people.”
Frank Chimero (Design Director)

3. How?

4. Information
Processing
Sensing &
Percepting
Acting &
Controlling
Medium
Acting &
Controlling
Information
Processing
Sensing &
Percepting
Environment
Human Human

5. Information
Processing
Sensing &
Percepting
Acting &
Controlling
Interface
Display
Machine
Operations
Commands
Environment
Human Machine

6. “
“The world and I are within one another.”
Maurice Merleau-Ponty (Philosopher)

7. What is Cognetics?
Ergonomics
Cognitive
Science
Cognetics

8. What is Ergonomics?
Ergonomics (Human Factors) is the scientific discipline
concerned with the understanding of interactions
among humans and other elements of a system
[humans, services, processes, things], and the profession
that applies theory, principles, data and methods to
design to optimize human well-being and overall system
performance.
Source: International Ergonomics Association

9. What is Cognetics?
Ergonomics
Cognitive
Science
Cognetics
Ethnographic analysis
User analysis
System analysis
Task analysis
Meta-analysis
etc.
Attention
Perception
Memory
Reasoning
Decision Making
etc.

10. Applications of Cognetics
Cognetics
HCI IxD UXD
Usability
Eng.
Service
Design
etc.

11. What is Cognetics?
Ergonomics
Cognitive
Science
Cognetics
MeasurementTools
InformationProcessing

12. “
“The Magical Number Seven, Plus or MinusTwo:
Some Limits on Our Capacity for Processing
Information.”
George Armitage Miller (Psychologist)

14. Wickens’ Model of IP

15. Human Processor Model (HPM)

16. How to Calculate HPM?
Parameters Mean Range
Eye MovementTime 230 ms 70-700 ms
Decay Half-life ofVisual Image Storage 200 ms 90-1000 ms
Visual Capacity 17 letters 7-27 letters
Decay Half-life of Auditory Storage 1500 ms 90-3500 ms
Auditory Capacity 5 letters 4.4-6.2 letters
Perceptual Processor CycleTime 100 ms 50-200 ms
Cognitive Processor CycleTime 70 ms 25-170 ms
Motor Processor CycleTime 70 ms 30-100 ms
EffectiveWorking Memory Capacity 7 chunks 5-9 chunks
PureWorking Memory Capacity 3 chunks 2.5-4.2 chunks
Decay Half-life of Working Memory 7 sec 5-226 sec
Decay Half-life of 1 ChunkWorking Memory 73 sec 73-226 sec
Decay Half-life of 3 ChunksWorking Memory 7 sec 5-34 sec
Source: The psychology of human-computer interaction

17. DohertyThreshold
Productivity soars when a computer and its
users interact at a pace (<400ms) that
ensures that neither has to wait on the other.
• Provide system feedback within 400ms in order to
keep users’ attention and increase productivity.

18. Fitts’s Law
The time to acquire a target is a function of
the distance to and size of the target.
• Make elements you wish to be easily selectable
large and position them close to users.
• This law especially applies to buttons, which the
purpose of these elements is to be easy to find and
select.

19. How many 3’s
1281768756138976546984506985604982826762
9809858458224509856458945098450980943585
9091030209905959595772564675050678904567
8845789809821677654876364908560912949686

20. How many 3’s
1281768756138976546984506985604982826762
9809858458224509856458945098450980943585
9091030209905959595772564675050678904567
8845789809821677654876364908560912949686

21. We are fundamentally lazy

22. “
“Less is More!”
Ludwig Mies van der Rohe (Architect)

24. Cognitive Load Theory
Cognitive load refers to the total
amount of mental activity imposed on
working memory in any one instant.
Cognitive
Load
Intrinsic Load
• Manage with
good instructional
sequencing
Extraneous
Load
• Reduce with good
instructional
design
Germane Load
• Maximize this

25. “
“To break a mental model is harder than
splitting the atom.”
Albert Einstein (Scientist &Theoretical Physicist)

27. Mental Models
Mental model is knowledge structure that individuals
construct to understand and explain their experiences.
The models are constrained by the individuals’ implicit
theories about these experiences, which can be more or
less accurate.
Johnson-Laird, 2001

28. Mental Models
Culture
Assumptions
Personalexperiences
Environments
Religion
Past
Beliefs
Family&Friends
Nation
etc.

29. “
“What if nothing exists and we're all in somebody's
dream?”
Woody Allen (American Director)

31. CounterfactualThinking
Counterfactual thinking is thinking about a past that did
not happen. This is often the case in “if only…”
situations, where we wish something had or had not
happened.
• Upward vs. downward
• Additive vs. Subtractive
• Self vs. other

32. CounterfactualThinking
Why do we have counterfactual thoughts?
• Risk Aversion
• Behavior Intention
• Goal-Directed Activity
• Collective Action
• Benefits and Consequences
Change Behavior

33. Behavioral ChangeTheories
Fogg Behavior Model:
B = MAT
• Motivation:
• Pleasure or Pain
• Hope or fear
• Social acceptance or rejection
• Ability
• Triggers

34. ‫منابع‬
1. The Humane Interface. by Jef Raskin
2. The Interface: IBM and the Transformation. of Design by John Harwood.
3. Cognition, Brain, and Consciousness. by Bernard Baars Nicole Gage
4. An introduction to human factors engineering. by Christopher Wickens
5. The Psychology of Human-Computer Interaction. by Thomas P. Moran and Allen Newell
6. The Psychology of Human-Computer Interaction. by Stuart K. Card, Allen Newell
7. Cognitive Load Theory. by Plass, Moreno
8. Cognitive Psychology. by Robert L. Solso, Otto H. MacLin
9. Wikipedia

35. ‫حــ‬‫امد‬‫عبـدی‬
#uxhiraz
‫بهشتی‬ ‫دانشگاه‬ ‫مغز‬ ‫و‬ ‫شناختی‬ ‫علوم‬ ‫پژوهشکده‬
‫پژوهشگر‬‫علوم‬‫شناختی‬(‫مدلسـازی‬‫محاسبا‬‫تی‬)
@hamedabdi/hamedabdi