1. nazlita@fsktm.um.edu.my1 General Human Factors

2. nazlita@fsktm.um.edu.my2 Human major senses : Vision Hearing Touch Taste Smell The central senses : Vision Hearing Touch

3. nazlita@fsktm.um.edu.my3 4 stages of human information processing  Encoding  Comparison  Response selection  Response execution plus  The processes of attention and memory

4. nazlita@fsktm.um.edu.my4 The perceptual system Visual Perception - use in design of visual interfaces Perceiving size and depth -visual angle, visual acuity perceiving brightness - the amount of light emitted by an object Perceiving colour - hue, intensity and saturation

5. nazlita@fsktm.um.edu.my5 2 approaches in explaining visual perception  The constructivist – perception involves the intervention of representation and memories  The ecological – perception is a direct process, information is simply detected rather than being constructed

6. nazlita@fsktm.um.edu.my6 The capabilities and limitation of visual processing Visual processing involves the transformation and interpretation of image Our expectation is an important factor in what will be interprated Eg. Ambiguous shapes, Muller-Lyer, Ponzo, text Perception - the process of becoming aware of objects representation - appearance of things

7. nazlita@fsktm.um.edu.my7 How do you interpret figure a and b? a b

8. nazlita@fsktm.um.edu.my8 Reading Steps of reading: 1) visual pattern perceived 2) decoded to an internal representation 3) syntactic and semantic analysis Eye, jerky movements (saccades), fixation (during which perception occurs) Adults read 250 word/minute Words are recognize as quickly as a single character Capitalizing words will effect speed and accuracy

9. nazlita@fsktm.um.edu.my9 RED BLACK YELLOW BLUE RED GREEN YELLOW BLACK BLUE BLACK RED YELLOW GREEN BLUE GREEN ZYP QLEKF SUWRG XCIDB WOPR ZYP QLEKF XCIDB SUWRG WOPR SUWRG ZYP XCIDB QLEKF WOPR

10. nazlita@fsktm.um.edu.my10 PadasuatuhariyanggelapAhmadtelahpergikepasar malamuntukmembeliikanyuSampaiDipasarmalamit udiatidakdapatmenjumpaiikanyutetapitejumpadeng anikanbilislalumembelinyadenganhatiyangriangria PadasuatuhariyanggelapAhmadtelahpergikepasarm alamuntukmembeliikanyuSampaiDipasarmalamitudi atidakdapatmenjumpaiikanyutetapitejumpadenganik anbilislalumembelinyadenganhatiyangriangria.

11. nazlita@fsktm.um.edu.my11 Hearing The human ear outer ear (protect and amplify) - processing sound middle ear (vibration occurs and transmit to inner ear) inner ear (send impulses to the auditory nerves) We can determine what and where 20 Hz < Frequency < 15 kHz

12. nazlita@fsktm.um.edu.my12 Others Touch - hot, cold, feeling of action such as picking up a glass, pressing the keys on the keyboard Important means of feedback Movement = reaction time + movement time movement time depends on the physical abilities ( age, fitness) reaction time (speed of senses)

13. nazlita@fsktm.um.edu.my13 Memory Sensory - iconic, echoic and haptic memory Short-term - scratch-pad for temporary recall 35*6 examples number sequence, chunking, meaning Long-term - episodic memory (events) semantic memory (facts, concepts and skills) remember, forgetting and retrieval

14. nazlita@fsktm.um.edu.my14 3 types of memory  Sensory store – holds information for a very brief period of time (a few tenth of a second)  Short-term memory store - holds limited information for a short period of time (a few seconds)  Permanent long-term memory store - holds information indefinitely

15. nazlita@fsktm.um.edu.my15 Thinking Reasoning - deductive, inductive and abductive Problem-Solving

16. nazlita@fsktm.um.edu.my16 Examples If the light is on then the day is getting darker The light is on Therefore…. ???? Some people are criminals Some criminals are murderers So.. ????

17. nazlita@fsktm.um.edu.my17 Statement: If a card has a vowel in one side it has an even number on the other. Which card will you need to pick up to test the statement? 4E7K

18. nazlita@fsktm.um.edu.my18 Examples There are 8 glasses of water in the kitchen. You need to carry them to the dinner table in the dining room. How would you go about doing the above task?

19. nazlita@fsktm.um.edu.my19 Learning Learning by doing, like driving a car Computer systems - manual, steps written in such a way that make user feel overloaded users use prior knowledge to use a new system Errors Skill acquisition

20. nazlita@fsktm.um.edu.my20 Errors 2 types : Mistakes : occur through conscious deliberation Slips : done unintentionally A captured error -frequent activity to intended action description error - action on wrong object data-driven error - external data interruption of action associative-activation error - internal thoughts interruption of action loss of activation error -forgetting something in the middle of action mode error - being in a state without knowing it

21. nazlita@fsktm.um.edu.my21 Skill acquisition Declarative - facts about the world Procedural - how we do things inability to absorb and put into action declarative instruction will lead to problems in learning how to use a system offer few options so declarative knowledge small later on can use more complicated systems

22. nazlita@fsktm.um.edu.my22 Mental-models, knowledge Knowledge - analogical, propositional, distributed network of general knowledge - the schemata Mental-models - the model people have of themselves, others, the environment and the things with which they interact

23. nazlita@fsktm.um.edu.my23 Why mental-models are important? To design interfaces that match user’s mental models >> not easy since actual mental model experiments are difficult to find What is the difference between images and mental models? Analogy of a movie, the frame and the short snippets of a movie

24. nazlita@fsktm.um.edu.my24 Structural and Functional models Structural - describes how devices and systems works Functional - describes how to use devices and systems

25. nazlita@fsktm.um.edu.my25 Metaphors What are metaphors? Descriptions of an abstract concept in a familiar form Verbal, Interface metaphors eg. Describing using the save and find files system in a word processor

26. nazlita@fsktm.um.edu.my26 Conceptual model A model of how human understand things around them. Cognitive model A representation of some aspect of the mind, involving the acquisition of knowledge (understanding, remembering, reasoning, learning)

27. nazlita@fsktm.um.edu.my27 Traditional cognitive framework in HCI Incomplete -individual user performing various tasks at the interface in an inadequate conceptual framework. More practical view of the cognitive framework The design of real systems for real people to carry out real work activities in real organizational settings.

28. nazlita@fsktm.um.edu.my28 2 approaches in cognitive psychology describing the activity of the brain Computational approaches – conceptualize the cognitive system in terms of goals, planning and action involve in task performance Connectionist approaches – simulate behaviour through using programming models

29. nazlita@fsktm.um.edu.my29 Distributed cognition A theory whose goal is to provide an explanation that goes beyond the individual. In distributed cognition “functional systems” is  The collection of actors  Computer systems and technology  The environmental setting

30. nazlita@fsktm.um.edu.my30 Social and Organizational Aspects Group commnunications: face-to-face, multi-party conversations computer-mediated multi-party communication constraints such as the images and sound that can be transmitted across the communication line appearance of users Organization - paperles, automated office, electronic cottage, global village