Lecture 4 from University of Derby's 'Cyberpsychology' module. The Psychology of Human-Computer Interaction. By Dr Simon Bignell

1. The Psychology of
Human-Computer Interaction
Dr Simon Bignell – Senior Lecturer in Psychology
s.bignell@derby.ac.uk
Week 4 – Cyberpsychology (5PS505)

2. Dr Simon Bignell – Cyberpsychology
Learning Outcomes of the Lecture
 To understand why psychologists should be involved in
designing new technologies.
 To consider some elements of human-computer interaction
in relation to psychology.
 To consider how new technologies impact on people and
society.

3. Contents
 What is HCI?
 Disciplines Contributing to Human-computer Interaction.
 Human-Computer Interaction as a Field of Study.
 Human Factors / Ergonomics.
 Systems Model vs User Model
 The User Interface
 Evolution of HCI ‘interfaces’.
 Human-Computer Dialog
 Common Ground
 Metaphors for Human-Computer Interaction
 Fitts’s (Fitts’)Law
 Ubiquitous Computing.
 Seminar Discussion and Activity.

4. Incidents: Information Overload / User Attention.
Three Mile Island, 1979
 What started as a minor malfunction in the system ended as the largest
commercial nuclear accident in the USA.
 Errors in information – signals indicated the reverse of the truth
 Poor placement of information – a caution tag fitted to one system obscured
the reading from another control system.
 Information overload – too much going on. 1500 alarms in either visual or
auditory modalities
 Poor controls – a single acknowledge button silenced all alarms rather than
allowed individual control.
 Operators were unable to break out of a cycle of assumptions that
conflicted with what their instruments were telling them.
 Mistakes are often blamed on operators rather than on the design of
the system.
Poor
interfaces
can lead to
disaster

5. Dr Simon Bignell – Cyberpsychology
What is ‘Human-Computer Interaction’ (HCI)?

6. Dr Simon Bignell – Cyberpsychology
What is ‘Human-Computer Interaction’ (HCI)?
 Human-computer interaction (HCI) is the study of how people
interact with computing technology.
 HCI study is the region of intersection between psychology and the
social sciences, on the one hand, and computer science and
technology, on the other.
 Human-Computer interface.
 Where people “meet” or come together with machines or
computer-based systems.
 ‘Physical interface’ (e.g. buttons, screens, menus, etc.)
 ‘Logical interface’.
 The model a system presents a user.
 Set of tasks available and how they’re organized.

7. What is ‘Human-Computer Interaction’ (HCI)?
 A key design activity is to design the user-interface.
 For every input and output the developer must consider the
interaction between the user and the computer.
 Because the interaction is much like a dialog between the user and the
computer, user-interface design is often referred to as ‘dialog design’.
 The field of HCI investigates how
people use computer systems, so that
better systems can be designed.
 One aspect is concerned with
technological innovation (e.g. better
input devices, like electronic pen etc.)
 The other aspect is concerned with the
human element (e.g. how people
reason, solve problems and interact
with computers).

8. Disciplines Contributing to Human-Computer Interaction
Computer
Science
Cognitive
Psychology
/Science
Artificial
Intelligence
HCI
Social &
Organisational
Psychology
Sociology Ergonomics

9. Human-Computer Interaction as a Field of
Study
 User-interface design techniques and HCI as a field of study evolved
from studies of human interaction with machines in general – human
factors engineering or ergonomics
 Formal study of human factors began in World War II, when aerospace
engineers studied the effects of arranging controls in cockpit.
 What the pilot does is the “human factor” that engineers realised was
beyond their control.

10. Dr Simon Bignell – Cyberpsychology
How does HCI / Human Factors differ from Experimental
Psychology?
 Experimental Psychology is the scientific study of mind, brain, and behavior
 Why do humans think and behave the way they do?
 HCI / Human factors is the study of human behavior in the context of
technological systems.
 How should we design a system to accommodate the way humans think
and behave?
 “The study of how humans accomplish work-related tasks in the
context of human-machine system operation, and how behavioral
and non-behavioral variables affect that accomplishment” Meister
(1989)

11. Dr Simon Bignell – Cyberpsychology
Human Factors
 Human Factors psychology examines the capabilities of humans and
how these constraints and abilities affect design.
 Therefore, it is concerned with cognitive issues and research
concerning humans’ interpretation of stimuli and our abilities to deal
with certain situations.
 The goal is to design systems with these capabilities and limitations in
mind.
 Cognitive issues that must be considered:
 Memory (span, retrieval, storage capacity).
 Visual and auditory capabilities/interpretations.
 Attention capacity (selective, focused, divided).
 Judgment of tones, size, loudness, brightness.
 Interpretation of coding (traffic lights).

12. Dr Simon Bignell – Cyberpsychology
Emergence of the field of Human-Computer
Interaction
 The field of human factors was associated with engineering,
since engineers designed machines.
 But engineers often found human factors frustrating (different
personality types).
 Gradually specialists emerged who drew on many disciplines
to understand people and their behaviour.
 Disciplines drawn on for HCI:
 Cognitive psychology.
 Computer science.
 Social psychology.
 Linguistics.
 Sociology.
 Anthropology.

13. Dr Simon Bignell – Cyberpsychology
The ‘User Model’ (of the system)…
 Is what the user thinks happens (within the system).
 Much of the user’s model is a logical model of the
system.
 A logical model can be detailed, so a user must know quite
a few details to operate the system.
 People want to learn by doing, but this inclines them to
opportunistically jump around in sometimes brittle learning
sequences.
 They want to reason things out and construct their own
understandings, but they often draw incorrect inferences
 They try to engage and extend prior knowledge and skill,
which can lead to interference or overgeneralisation.

14. Dr Simon Bignell – Cyberpsychology
The ‘System Model’…
 Is what really happens (within a
complex computer systems).
 Designer’s model (of the system).
 How the designer sees and
understands the system.
 Problems with user interfaces can be
considered as resulting from
‘mismatches’ between the user’s
model of the system and the designer’s
model.
 Leads to attempt to study how user’s
view systems and how designer’s view
systems – can be a big gap!

15. Dr Simon Bignell – Cyberpsychology
The User Interface: GUI / Menus
 Users are given predetermined choices, they are
often part of a WIMP interface (point & click).
 Windows and window managers
 Icons
 Menus
 Pointing devices.
 Enforce a hierarchy on the user’s goals.
 Represent well-trodden paths - you can do only what the designer
envisioned.

16. Dr Simon Bignell – Cyberpsychology
 Many people think of the user interface as a component
added to the system near the end of the development
process.
 This view is changing as user interfaces become more
important and systems become more interactive.
 To the end user, the user interface is the system
 The user interface is everything the end user comes
into contact with while using the system – physically,
perceptually and conceptually.
 Therefore, consideration of the user interface should
come early in the development process.
The User Interface: GUI / Menus

17. Dr Simon Bignell – Cyberpsychology
The User Interface: Direct
Manipulation Interfaces
 Post-WIMP interface’s are found on devices that do not have room for a mouse.
Mobile devices, phones, iPods, iPads, PDAs etc.
 Representations behave as if they were the objects they represent.
 Involves dragging, selecting, opening, closing and zooming actions on virtual
objects.
 This reduces the distance between users and their goals.
 Consistent with “what you see is what you get” (WYSIWYG).
 Exploit’s users’ knowledge of how objects behave in the physical world (various
metaphors).
 Continuous representation of the objects of interest.
 Physical actions, not complex syntax.
 Easy to learn, easy to remember.

18. Dr Simon Bignell – Cyberpsychology
 Novices can learn the basic functionality quickly.
 Experienced users can work extremely rapidly to
carry out a wide range of tasks, even defining
new functions.
 Intermittent users can retain operational
concepts over time.
 Error messages are rarely encountered.
 Users can immediately see if their actions are
furthering their goals and if not, do something
else.
 Users experience less anxiety.
 Users gain confidence and mastery and feel in
control.
Why are Direct Manipulation interfaces enjoyable?

19. Dr Simon Bignell – Cyberpsychology
“People are different from computers, and human-human
interaction is not necessarily an appropriate model for
human operation of computers. Since computers can
display information 1000 times faster than people can
enter commands, it seems advantageous to use the
computer to display large amounts of information and
allow novice and intermittent users simply to choose
among the items.” (Schneiderman, 1986)
Why are Direct Manipulation Interfaces Enjoyable?

20. Dr Simon Bignell – Cyberpsychology
Some problems with Direct Manipulation interfaces
 Sometimes: information overload or screen clutter.
 Not all tasks can be represented by objects.
 it’s hard to represent abstract things.
 DM must function in the “here” and “now”.
 icons can be just as cryptic as words.
 With DM, user is responsible for doing everything; but some tasks are
better achieved by delegating.
 e.g. spell checking.
 repetitive actions are tedious!
 Moving a mouse around the screen can be slower than pressing
function keys to do same actions.

21. Dr Simon Bignell – Cyberpsychology
Evolution of HCI ‘interfaces’
 1950s - Interface at the hardware level for engineers - switch
panels.
 1960-70s - Interface at the programming level - COBOL,
FORTRAN.
 1970-90s - Interface at the terminal level - command languages.
 1980s - Interface at the interaction dialogue level - GUIs,
multimedia.
 1990s - Interface at the work setting - networked systems,
groupware.
 2000s - Interface becomes pervasive.
 RF tags, Bluetooth technology, mobile devices, consumer
electronics, interactive screens, embedded technology,
information appliances.

22. Dr Simon Bignell – Cyberpsychology
Human-Computer Dialogue
Person - Person Computer - Computer

23. Human-Computer Dialogue
 Some kinds of human conversations are scripted - who takes the initiative is
relatively fixed.
 In other kinds of conversation, neither person takes all the initiative.
 What can go wrong?
 A dialog can be under-determined.
 E.g. when the user is mystified about what to do next and is forced to
take the initiative (a blank screen, cryptic commands).
 A dialog can be over-determined.
 E.g. When a system is authoritarian and takes too much initiative
(unnatural constraints).

24. Dr Simon Bignell – Cyberpsychology
Human-Computer Dialogue
 Ideally, initiative should be
flexible.
 Interfaces that take the initiative
are better for novices.
 Interfaces that let the user take
the initiative are better for
experts.
An interface is over- or under-
determined with respect to a
particular user.

25. Dr Simon Bignell – Cyberpsychology
Human-Computer Dialogue
 Exploring and browsing:
 Similar to how people browse information with existing
media (e.g. newspapers, magazines, libraries,
pamphlets)
 Information is structured to allow flexibility in way user
is able to search for information.
 Browsers, hypertext, links
 Virtual reality will present new ways of interacting.

26. Dr Simon Bignell – Cyberpsychology
Human-Computer Dialogue

27. Dr Simon Bignell – Cyberpsychology
Different styles of interacting
 Commands
 typing commands via keyboard; function key shortcuts
 Menus
 selecting from pre-determined choices
 Direct manipulation
 acting on objects and interacting with virtual objects
 Conversational dialogue systems
 interacting with the system as if having a conversation
 Exploring, browsing, & foraging for information
 finding out and learning things
 browsers (different from menus)

28. Dr Simon Bignell – Cyberpsychology
Eliza, Computer Therapist
 ELIZA is a computer program and an early example of primitive
natural language processing (NLP).
 http://psych.fullerton.edu/mbirnbaum/psych101/Eliza.htm
 http://www.manifestation.com/neurotoys/eliza.php3
 ELIZA was written at MIT by Joseph Weizenbaum between 1964 and
1966.
 Also: A.L.I.C.E. (Artificial Linguistic Internet Computer Entity)
 http://alice.pandorabots.com
 When the original ELIZA first appeared in the 60's, some people
actually mistook her for human.
 The illusion of intelligence works best, however, if you limit your
conversation to talking about yourself and your life.

29. Dr Simon Bignell – Cyberpsychology
Turing Test
 The Turing test is a test of a machine's ability to
exhibit intelligent verbal behaviour similar to that
of a human.
 The standard interpretation of the Turing test, in
which player C, the interrogator, is tasked with
trying to determine which player – A or B – is a
computer and which is a human.
 The test was introduced by Alan Turing in his
1950 paper ‘Computing Machinery and
Intelligence’, which opens with the words: “I
propose to consider the question, 'Can
machines think?”
 Later rephrased as: “Are there imaginable
digital computers which would do well in
the imitation game?”

30. Dr Simon Bignell – Cyberpsychology
‘Common Ground’ in HCI
 Successful grounding in communication requires parties to coordinate both the
content and process.
 Computer-mediated communication presents potential barriers to establishing
mutual understanding.
 Grounding occurs by acknowledgement of understanding through verbal,
nonverbal, formal, and informal acknowledgments.
 But commuter-mediated communications reduce the number of channels
through which parties can establish grounding.
 ‘Common Ground’ or ‘Grounding’ in
communication was proposed by Herbert Clark &
Susan Brennan.
 It comprises the collection of mutual knowledge,
mutual beliefs, and mutual assumptions, that is
essential for communication between two people.

31. Dr Simon Bignell – Cyberpsychology
 The design of human-computer interaction is a
problem that primarily involves the designer’s
meaning and the user’s understanding.
 When software use is successful…
 The designer and the user carry out a kind of
collaboration but both have to work at it.
 The designer’s meaning (ideally) becomes the
user’s understanding.
 A variety of linguistic and nonlinguistic signals
are used. E.g., labels, icons, actions, sounds,
messages, etc.
 Signal use is really language use.
 Meaning and understanding depend on the notion of ‘common ground’.
‘Common Ground’ in HCI

32. Dr Simon Bignell – Cyberpsychology
‘Common Ground’ in HCI
 When the normal function of common ground in a language use
setting is impaired, people are forced to work harder cognitively to
accomplish their goals
 What we call ‘human-computer interaction’ takes place in the
secondary layer of software use
 In this layer, the user participates in a direct interaction with the computer
(as opposed to the designer).
 The interaction is designed to resemble a joint activity in a face-to-
face setting…
 But this setting is not equivalent with a face-to-face setting between
people
 The user and the computer use different communication languages and
their tools for conveying and receiving are mismatched.

33. Dr Simon Bignell – Cyberpsychology
Metaphors for Human-Computer Interaction
 The term metaphor describes the overall “concept” you may use to
organize all the objects and actions in an interface into a coherent
whole.
 Having a metaphor can tell you how you might use something.
 Three major metaphors in HCI…
 Direct manipulation metaphor
 The user interacts directly with objects on the display screen.
Objects are made visible so the user can point at them and
manipulate them with the mouse or arrow keys
 Desktop metaphor.
 The display screen includes an arrangement of common desktop
objects.
 Document metaphor.
 Data is conceptualized as physical paperwork.

34. Dr Simon Bignell – Cyberpsychology
Useful Metaphors
 Text editing as using a typewriter.
 Voice mail as answering machine or mailbox.
 Data as files (in folders or directories), represented
as icons on desktop in windows.
 Deleting a file as throwing it in the trash.
 Applications as tools (with icons).
 Programming as building objects.
 Programming as directing actors on a stage.
 Applications as agents.

35. Dr Simon Bignell – Cyberpsychology
Example: Fitts’s (Fitts’) Law

36. Dr Simon Bignell – Cyberpsychology
Example: Fitts’s (Fitts’) Law
 Predicts that: “The time required to rapidly move to a
target area is a function of the distance to the target
and the size of the target.”
 proposed by Paul Fitts in 1954.
 Fitts's law is used to model the act of pointing, either by physically
touching an object with a hand or finger, or virtually, by pointing to an
object on a computer monitor using a pointing device.
 Buttons and other GUI controls should be a reasonable size; it is
relatively difficult to click on small ones.
 Edges and corners of the computer monitor are particularly easy
to acquire with a mouse, touchpad or trackball.

37. Dr Simon Bignell – Cyberpsychology
Augmented Reality
 Augmented reality (AR) is a live direct or
indirect view of a physical, real-world
environment whose elements are
augmented (or supplemented) by computer-
generated sensory input such as sound,
video, graphics or GPS data.
 Techniques include speech recognition
systems that translate a user's spoken
words into computer instructions and
gesture recognition systems that can
interpret a user's body movements by visual
detection or from sensors embedded in a
peripheral device such as a wand, stylus,
pointer, glove or other body wear.

38. Ubiquitous Computing: In contrast to desktop computing,
ubiquitous computing can occur using any device, in any
location, and in any format.

39. Dr Simon Bignell – Cyberpsychology
Recommended Reading
 Don Norman: The
Design of Future Things
 http://youtu.be/wQmw
EjL6K1U?list=PL818A
65742B734849

40. Any questions?

41. Seminar Activity 1: Discuss
1. You have been commissioned to evaluate
a new generation mobile phone. Describe
how you would fulfil this commission,
justifying your choice of methodology.
2. Is it better to interact with computational
devices through direct manipulation or by
conversing with agents? Why?
3. A science fiction writer describes humans
in the future as ‘socially isolated without
skills at human interaction’. Discuss why
this view fails to take into account the wide
range of ways that computers facilitate
communication.

42. Seminar Activity 2: Human
Considerations in Software Design
Consider 5 different users:
1. A University of Derby student trying to do research for an essay on the Web.
2. An adult on using tax preparation software at home.
3. A young woman with Cerebral Palsy who is typing coursework for a module.
4. A child playing a computer-video game.
5. An octogenarian grandparent sending email to faraway grandchildren.
Questions
• Q: What do we need to know about each of them in order to make the
software that they are using accessible?
• Q: What kinds of things do we need to consider in our designs?
• Q: What do we know about Psychology that will guide our designs?