1. What is HCI and where does GUI design fit in?
Lecture 1 CSE3030

2. Outcomes of the lecture
Be able to describe the field of HCI
Be able to argue whether or not specific subjects should fall within the field
Understand how the design of graphical interfaces fit within the broader field of HCI

3. HCI defined
Human-computer interaction is a discipline concerned with the design, evaluation and implementation of interactive computing systems for human use and with the study of major phenomena surrounding them
This is a ‘working definition’
From the ACM SIGCHI (Association of Computing Machinery, Special Interest Group for Human-Computer Interaction)

4. What is and isn’t HCI?
On the H side?
On the C side?

5. Three Mile Island

6. The Control Panel

7. Palm Beach Ballot

9. Beyond intuition
Human-machine system designers cannot just rely on intuition – too many complex factors are operating.
Instead, need to look to:
High level theories/models/principles
Middle level principles
Specific & practical guidelines
Intuition – that looks good or right to me is not an adequate design criteria
High level theories – human factors
Middle level - specific computer interface
Low level – guidelines for types of computer applications - eg
style guides for a particular look and feel,
widget-level guidelines

10. HCI principles
General design principles involve being aware of, and catering to, human abilities, skills and differences (human factors). These apply to design of any human-machine system e.g. cars, playgrounds, lifts, phones, computers.
Designing human-computer interaction is a particular area of human factors design with specific principles and guidelines.
Designing user interfaces is specific area of HCI and concerns general principles & low level concerns.
High level theories – human factors
Middle level – specific computer interface
Low level – guidelines for types of computer applications - eg
style guides for a particular look and feel,
widget-level guidelines

11. HCI: Three basic principles
People want ease of use – usually provided by simplicity and transfer of existing experience.
The user view is different to the system engineers view. Often engineers design systems to perform a set of functions rather than with the user in mind.
Computers and people are both better at some tasks than others – however they are better at different tasks.
E.g. we see a word spelt jomp our brain says its probably meant be jump but a computer is totally literal.
See sh p. 84.

12. Human factors
Invention of machines (cars, airplanes, electronic devices ...) taxed people’s sensorimotor abilities to control them.
Even after high degree of training, frequent errors (often fatal) occurred.
Result: human factors became critically important.

13. Human factors
However, designers still often consider cost and appearance over human factors design.
People tend to blame themselves when errors occur:
“I was never very good with machines”
“I knew I should have read the manual!”
“Look at what I did! Do I feel stupid!”
Bad design not always visible, but sometimes it is very obvious!

14. Human factors How many of you can program or use all aspects of your:
digital watch? Fax machines?
VCR?
stereo system (especially car stereos)
unfamiliar water taps?
“..no need to understand the underlying physics ..(or code) of everything …simply the relationship between the controls and the outcomes” - Donald Norman – “The design of everyday things”
Technology is getting more complicated.
Different taps.

15. Related Fields Computer science Psychology Sociology and anthropology
application design and engineering of human interfaces
Psychology
the application of theories of cognitive processes and the empirical analysis of user behavior
Sociology and anthropology
interactions between technology, work, and organization
Industrial design
interactive products

16. Design process
Important to consider the What, Why and How of design process for an application before you even begin to think about the interface, coding, etc.
User needs and usability goals must be addressed at the beginning of the design process. Designers can make incorrect assumptions about the requirements.
Designers are really often not in tune with the users needs - even their basic requirements and situations

17. WAP mobile phone example
People want to be kept informed of up-to-date news wherever they are - reasonable
People want to interact with information on the move - reasonable
People are happy using a very small display and using an extremely restricted interface - unreasonable
People will be happy doing things on a cell phone that they normally do on their PCs (e.g. surf the web, read , shop, bet, play video games) - reasonable only for a very select bunch of users
See
Was WAP a solution looking for a problem?
Worst aspect - time taken to get info and generally paying by time used.

18. User needs & usability 63% of large software projects go over cost
Managers gave four usability-related reasons
users requested changes
overlooked tasks
users did not understand their own requirements
insufficient user-developer communication and understanding
(Greenberg, 2001)

19. Human factors Norman – “Design of everyday things”
Most failures of human-machine system are due to poor designs that don’t recognize peoples’ capabilities and fallibility's
This leads to apparent machine misuse and “human error”
Good design always accounts for human capabilities.

20. Darn these hooves. I hit the wrong switch again
Darn these hooves! I hit the wrong switch again! Who designs these instrument panels, raccoons?

21. Human characteristics
Designer must take into account variations in human senses and motor abilities:
Vision – e.g. depth, contrast, colour blindness, and motion sensitivity.
Hearing - e.g. audio cues must be distinct.
Touch: e.g. keyboard and touchscreen sensitivity.
Motor control/ hand-eye coordination e.g use of pointing devices.
Physical strength, coordination.
Not yet for taste and smell!

22. Cognitive and perceptual abilities
There are many aspects to human cognitive abilities. For example:
short-term memory
long-term memory and learning
problem solving, decision making
attention and set (scope of concern)
perception & recognition

23. from Science magazine
In 1988, the Soviet Union’s Phobos 1 satellite was lost on its way to Mars, when it went into a tumble from which it never recovered. “not long after the launch, a ground controller omitted a single letter in a series of digital commands sent to the spacecraft. And by malignant bad luck, that omission caused the code to be mistranslated in such a way as to trigger the [ROM] test sequence [that was intended to be used only during checkout of the spacecraft on the ground]”
Failure of attention, memory, in controller
OR failure in design process???

24. Factors affecting cognitive, perceptual & motor performance
Arousal, vigilance, fatigue
Cognitive (mental) load
Boredom, isolation, sensory deprivation
Anxiety and fear
Illness, ageing
Drugs and alcohol
Circadian rhythms, sleep deprivation
Was that controller tired, overexcited, trying to do /remember too many things at once, very anxious, unwell, old, drunk, hadn’t slept for two days…

25. Personality factors
There is no single taxonomy for identifying user personality types.
Designers must be aware that populations are subdivided and that these subdivisions have various responses to different stimuli.
Myers-Briggs Type Indicator (MBTI)
extroversion versus introversion
sensing versus intuition
perceptive versus judging
feeling versus thinking
Why does this matter?
For example: sensing types – good at routine and precision whereas intuitive types like change and challenge but are often imprecise…

26. Awareness of cultural and international diversity
Characters, numerals, special characters, grammar, spelling
L-to-r vs r-to-l vs vertical input & reading
Date and time formats
Numeric and currency formats
Telephone numbers and addresses
Names and titles (Mr., Ms., Mme.)
Social-security, national id & passport numbers
Etiquette, policies, tone, formality, metaphors
See Preece etc slides for examples

27. Which are universal and which are culturally-specific?
Learned arbitrary conventions - like red triangles for warning
Buddhists – white is mourning, west is used in weddings for celebration
4 is unlucky in Chinese, 13 in west…

28. Users with disabilities
Need to plan early to accommodate users with disabilities as costs may be very high later
Some countries have laws which specify requirements to comply with equal opportunity legislation
See list of guidelines

29. Current Computing Systems
Human factors and HCI design impact on all of the large variety of current and emerging computer systems.
However, the impact of various human factors and design decisions depends on the nature of the system.

30. System types: Critical systems
Examples: air traffic control, nuclear reactors:
High costs, reliability and effectiveness are expected.
Lengthy training periods are acceptable to provide error-free performance.
Subject satisfaction is less an issue due to well motivated users. Retention via frequent use and practice.
Designing this type of system will require quite different approach and specific evaluation criteria

31. Systems types: Commercial/industrial
Examples: banking, production control, banking, insurance, order entry, inventory management, reservation, billing, and point-of-sales systems:
Lower cost may sacrifice reliability.
Training is expensive, learning must be easy.
Speed and error rates are relative to cost, however speed is the supreme concern. Subject satisfaction is fairly important to limit operator burnout.
Often have to train lots of people, and may have large staff turnover also.
Eg system to support directory assistance found that .8 secs reduction in call time meant 40 million per annum savings

32. System types: Office/home/entertainment
Examples: Word processing, electronic mail, computer conferencing, and video games, education:
Choosing functionality is difficult because the population has a wide range of both novice and expert users.
Competition causes the need for low cost.
Subject satisfaction is very important.

33. System types: ???
Examples: Artist toolkits, statistical packages, and scientific modelling systems
Benchmarks are hard to describe due to the wide array of tasks
With these applications, the computer should "vanish" so that the user can be absorbed in their task domain.
Difficult to design and evaluate….

34. System engineering versus interface design
System engineering evaluated by:
Coverage of task functionality.
Reliability, security, integrity of system and data.
Standardization, consistency and portability.
Time and budget considerations.

35. User interface evaluation
Depends largely on human factors criteria:
1. Learning time
2. Performance speed
3. Error rates of users
4. Retention over time
5. Subjective satisfaction
How long does it take for typical members of the community to learn relevant task?
How long does it take to perform relevant benchmarks
How many and what kinds of errors are commonly made during typical applications?
Frequency of use and ease of learning help make for better user retention
Allow for user feedback via interviews, free-form comments and satisfaction scales.

36. HCI is concerned with… Humans and machines jointly performing tasks
The structure of communication between human and machine
Human capabilities to use and learn to use machines
Algorithms and programming of the interface
Engineering concerns that arise in designing and building interfaces
The process of specifying, designing, and implementing interfaces
Design trade-offs

37. 5 Areas of HCI The nature of human-computer interaction
Use and context of computers
Human characteristics
Computer system and interface architecture
Development processes

39. Nature of Human-Computer Interaction
Overviews of, and theoretical frameworks for, topics in human-computer communication

40. N1 The Nature of Human-Computer Interaction
Points of view
HCI as communication
agent paradigm, tool paradigm
Human / system / tasks division
Objectives or goals
productivity, user empowerment
History and intellectual roots
HCI as an academic topic
journals, literature
relation to other fields
science vs. engineering vs. design aspects

41. Use and Context of Computers
Applications of computers
Applications and appropriate interfaces
The general social, work, and business context
In addition to technical requirements, an interface may have to
satisfy quality-of-work-life goals of a labor union
meet legal constraints on "look and feel“
position the image of a company in a certain market
General problems of fitting computers, uses, and context of use together

42. U1 Social Organization and Work
The human as an interacting social being
The nature of work
Human and technical systems mutually adapt to each other and must be considered as a whole
Models of human activity, groups, organizations
Models of work, workflow, cooperative activity
Organizations as adaptive open systems
Impact of computer systems on work and vice versa
Computer systems for group tasks, case studies
Quality of work life and job satisfaction

43. U2 Application Areas Characterization of application areas
Document-oriented interfaces
Communications-oriented interfaces
Design environments: programming environments, CAD/CAM
On-line tutorial and help systems
Multimedia information kiosks
Continuous control systems: (process control systems, simulators, cockpits, video games)
Embedded systems (Copier controls, elevator controls, consumer electronics and home appliances)

44. U3 Human-Machine Fit and Adaptation
Design addresses ‘fit’ between the object and its use
Adjustments can be made
(1) at design time or at time of use
(2) by changing the system or the user
(3) by the users or by the system.
Adaptive systems
Theories of system adoption
Customizing and tailoring
Compatible users and systems
User adaptation: learning, training
User guidance: help, documentation, error-handling

45. Human Characteristics
human information-processing characteristics
how human action is structured
the nature of human communication
human physical and physiological requirements

46. H1 Human Information Processing
The human as a processor of information.
Models of cognitive architecture
Phenomena and theories of
memory
perception
motor skills
attention and vigilance
problem solving
learning and skill acquisition
motivation
Users' conceptual models
Models of human action
Human diversity, including disabled populations

47. H2 Language, Communication and Interaction
Language as a communication and interface medium
Aspects of language: syntax, semantics, pragmatics
Formal models of language
Conversational interaction
turn-taking, repair
Special languages
graphical interaction, query, command, production systems, editors
Interaction reuse
history lists

48. H3 Ergonomics Human anthropometry and workspace design
Arrangement of displays and controls
Human cognitive and sensory limits
Sensory and perceptual effects of display technologies
Control design
Fatigue and health issues
Furniture and lighting design
Temperature and environmental noise issues
Design for stressful or hazardous environments
Design for the disabled

49. Computer System and Interface Architecture
Machines have specialized components for interacting with humans
Transducers for moving information physically between human and machine
Have to do with the control structure and representation of parts of the interaction

50. C1 Input and Output Devices
Technical construction of devices
Input devices
Mechanics and performance
Devices for the disabled
Handwriting and gestures, virtual keyboard
Speech input
Eye tracking, EEG, other biological signals
Output devices
Sound and speech output
3D displays, motion (e.g., flight simulators)
Device weight, portability, bandwidth, sensory mode

51. C2 Dialogue Techniques Techniques for interacting with humans
Dialogue Interaction Techniques
Dialogue type and techniques
Navigation, orientation, error management
Agents and AI techniques
Multi-person dialogues
Dialogue Issues
Real-time response
Manual control theory
Supervisory control, automatic systems, embedded systems
Standards
"Look and feel," intellectual property protection

52. C3 Dialogue Genre Conceptual uses for the technical means
Concepts arise in any media discipline (film, graphic design)
Interaction metaphors
Content metaphors
Persona, personality, point of view
Workspace models
Transition management
Techniques from other media (film, theater, graphic design)
Style and aesthetics

53. C4 Computer Graphics
Concepts from computer graphics that are useful for HCI
Geometry in 2- and 3-D space, linear transformations
Graphics primitives and attributes
Solid modeling, splines, surface modeling, hidden surface removal, animation, rendering algorithms, lighting models
Colour representation, colour maps, colour ranges of devices

54. C5 Dialogue Architecture
Software architectures and standards
Layers and windows
Screen imaging models (e.g. postscript)
Window manager models, analysis of major window systems
Models for specifying dialogues
Multi-user interface architectures
Standardization and interoperability

55. Development Process Both design and engineering
The methodology and practice of interface design
The relationship of interface development to the engineering of the rest of the system

56. D1 Design Approaches The process of design
Alternative system development processes
Choice of method under time/resource constraint
Task analysis techniques
Design specification techniques
Design analysis techniques
Graphic design basics
Industrial design basics
Design case studies and analyses of design

57. D2 Implementation Techniques and Tools
Tactics and tools for implementation.
Relationships among design, evaluation, and implementation
Independence and reusability, application independence, device independence
Prototyping techniques
Dialogue toolkits
Object-oriented methods
Data representation and algorithms

58. D3 Evaluation Techniques
Philosophy and methods for evaluations
Productivity
Measures
Time
Errors
Learnability
Design for guessing
Preference
Testing techniques, link testing to specifications
Formative and summative evaluation
Methods from psychology and sociology
Ethics

59. D4 Example Systems and Case Studies
Classic designs that serve as examples of HCI
Command-oriented
Graphics-oriented
Frame-based
User-defined

61. Where does GUI fit in? U3 human-machine fit and adaptation
H1 human information processing
H2 language, communication and interaction
C1 input and output devices
C2 dialog techniques
C3 dialogue genre
C4 computer graphics
C5 dialogue architecture
D1 design approaches
D3 evaluation techniques

62. References
ACM Special Interest Group on Computer-Human Interaction (SIGCHI). ACM SIGCHI is an international, interdisciplinary forum for the exchange of ideas about the field of human-computer interaction.
Norman, D. A. (1998). The Design of Everyday Things. New York, New York, USA: Basic Books.
Shneiderman, B., & Plaisant, C. (2005). Designing the User Interface: Strategies for Effective Human-Computer Interaction (Fourth ed.). USA: Pearson Education, Inc.
Stone, D., Jarrett, C., Woodroffe, M., & Minocha, S. (2005). User Interface Design and Evaluation. San Francisco, California, USA: Elsevier.