Advanced HCI Effective Interaction Pt 1

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Advanced HCIEffective Interaction Pt 1

• This lecture explores some of the theories used
  to explain peoples behaviour when they interact
  with technological products.
• HCI theories are dealt with at various points in
• Preece, Sharp and Rogers, Benyon, Turner and
  Turner, and Dix, Finlay, Abowd and Beale. (Refer
  to these texts if you are seeking more detail)
• There are also further notes on the website, in
  addition to a copy of
• Rogers, Y. (2004) New theoretical approaches for
  HCI. ARIST Annual Review of Information Science
  and Technology, 38, 2004. 87-143.

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Operating a computer

• 1980
• Joe is new to computing. It has taken him several
  weeks to learn how to operate the computer. He
  types in commands and the computer carries out
  his instructions.
• Sometimes he forgets the right command to type
  and has to waste time looking for help. He can
  only get help on the command that he needs, and
  if he has forgotten it
• At other times Joe makes an error by mistyping a
  command. He is surprised when the computer
  doesnt do what he wanted or when it gives him an
  error message he doesnt understand.
• When he wants to print a document he has to first
  select the font he wants on his printer and then
  type the PRINT command followed by some other
  characters that tell the printer what he wants.
  If he gets this wrong he has to do it all again.

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Operating a computer

• Early 1980s computers
• Difficult to learn Difficult to use
• User view Tasks not carried out as user wanted
• Designer view Users do unpredictable things
• How can we make this easier and more enjoyable
  for the user?
• Need to understand
• What the user expects the computer to do
• How the user would prefer to do the task
• What the user is likely to do, and why
• What is the easiest way of doing this?
• Search is on for explanation of peoples
  behaviour when using computers
• To inform the design of existing tasks easier to
  learn use
• To discover new possibilities, new ways of doing
  things

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Explaining behaviour, scientifically

• Computer as brain
• Memex Vannevar Bush, As We May Think 1945
• memory ex tender theoretical analogue computer
• device linked to a library able to retrieve
  books films
• ability to follow cross references between
  documents (precursor of hypertext)
• Memex comparison between the device the
  operation of the brain
• storing in memory
• retrieving from memory
• linking memories

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Explaining behaviour, scientifically

• Brain as computer
• Cognitive Psychology
• how people perceive, understand, evaluate
  think
• brain as information processor
• receiving input
• encoding material
• storing material
• retrieving material

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Explaining behaviour, scientifically

• Similarity of models
• Shannon Weavers Communication Model
• 1950s
• Signal processing

Modal Model of Memory (Based on Atkinson
Shiffrin, 1968)
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Explaining behaviour, scientifically
The conscious mind. This is where you do your
thinking, reasoning, reflecting. Often referred
to as short-term memory. This is associated
with reflective cognition

• But models can be quite simple

The greater part of the mental system. Massive
storehouse of everything you have learnt,
instinctive behaviour patterns, skills we have
learnt etc. Sometimes called long-term memory.
Associated with experiential cognition.
Interactions
Your inner Mental world
The outer world
Imagine an active, distorting simplifying
filter which forms the boundary between your
inner, mental, world and the outside
world.Filter shaped by personal experience and
learning.Causes interpretation of the world in
ways that are familiar, so you see what you
expect to see a familiar world is easier to deal
with. It causes everyone to interpret the world
differently.
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Models of Cognition

• Criticisms of early models of cognition
• Assumes people use mental model to work out what
  to do in a situation
• Using mental models to explain behaviour
• Not much good outside controlled experiments
• Alternative view (Norman others)
• People use the situation to remind/indicate what
  to do
• External cognition
• Knowledge in the head (what we have learnt and
  can recall)
• Knowledge in the world (what we can recognise in
  the environment)

Things in the world
You
Knowledge in the World Knowledge in the Head
Distributed Cognition
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Distributed Cognition

• Reduce cognitive load for user
• Recognition better than recall
• What icons does the user recognise easily?
• What is the best way to group them?
• what we can recallv. what we can recognise

Knowledge in the world
Knowledge in the head
ATTRIBBREAKCDDISKCOPYDIRFINDFINDSTRFORMATG
OTOLABELMKDIR
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From type and swear to point click
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Communicating models of use

• look feel of a well-designed device
• Communicates the designers intention
• Makes it easier for user to see how it should be
  used
• This phenomenon can be summed up thus

Can you add the missing labels?
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Just Click It
Image from OK/Cancel www.ok-cancel.com/
comic/104.html
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Affordance

• The ability to determine how something should be
  used, especially what you can do with it hinges
  on affordance (Norman, 1988)
• An affordance is a relationship between an object
  and a person who encounters it.
• The form or appearance of the object invites, or
  affords, an activity to be carried out with it.

How do we open these doors?
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Affordance

• We must understand the needs and abilities of
  the prospective users. But equally we must
  understand the capabilities and limitations of
  technologies in order to know the possibilities
  they offer for design. (Gaver, 1991 p.79)
• Where is the affordance?
• In the object?
• In our perception of the object?
• In the social context in which we encounter the
  object?

Here?
Here?
Here?
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Situated Action

• Origins in social anthropology (Suchman, 1987)
• Accounts of relations among people, and between
  people and the historically and culturally
  constituted worlds they inhabit.
• To explain the relationship between structures
  of action and the resources and constraints
  afforded by physical and social circumstances.
  (my italics)
• Holistic view
• Belief You cannot look at technology, or the
  people using it, or the situation it is used in,
  in isolation.
• Method ethnographic (observations, interviews,
  note-taking of a particular setting)
• Findings people often dont use technology in
  the way it was intended
• Recommendations designers need to know how
  people go about tasks before designing technology

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Situated Action

• Suchman (1987) study of people using help system
  for photocopier
• Design based on preconceived model of how user
  will use system
• Novice users frequently unable to use machine
• User continues to act by doing what they think is
  appropriate in this situation
• Designers need to base design on users
  situation not on some abstract model

Image fom http//www.balanceconsulting.ca/_photos/
photocopier.jpg
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Ethnography

• Similar to Situated Action and Distributed
  Cognition approaches
• Used to explicate details of various work
  practices through which actions interactions
  are achieved
• Used to analyze workplace settings
• London Underground control centre (Heath and
  Luff, 1991)
• Air traffic control (Bentley et al., 1992)
• Results in very detailed accounts of workplace
  practice
• Often exposing taken for granted working practice
  central to how system is being used
• The only way to come to a good understanding of
  the effectiveness of a software system is to
  understand how it features as part and parcel of
  a set of working practices, as embodied by a
  group of people actually using the system to do
  real work in real setings. (Dourish, 2001, p.62)

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HCI Contributing research fields (not exhaustive)
Design
Design
Ergonomics and human factors
Ergonomics and human factors
Semiotics
Semiotics
Psychology
Psychology
HCI
HCI
Ethnography
Ethnography
Computer Science
Computer Science
Engineering
Engineering
Language
Language
Sociology
Sociology
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Viewpoints

• Often used to explain the use of technology in a
  particular situation
• Many overlaps sometimes, contradictions
• Remember, we all see the world differently -
  including HCI practitioners
• General move is away from static cognitive models
  towards holistic views

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References

• Atkinson, R.L. and Shiffrin, R.M., 1968. Human
  memory A proposed system and its control
  processes. In K.W. Spence and J.T. Spence (eds.),
  The psychology of learning and motivation. Vol.2.
  London Academic Press.
• Bentley, R., Hughes, J.A., Randall, D., Rodden,
  T., Sawyer, P., Shapiro, D. and Sommerville, I.,
  Ethnographically-Informed Systems Design for Air
  Traffic Control. In Proceedings of ACM CSCW'92
  Conference on Computer-Supported Cooperative Work
  (Toronto, Canada, 1992) ACM Press, 123-129.
• Dourish, P. (2001). Where the Action Is The
  Foundations of Embodied Interaction. Cambridge
  MIT Press.
• Gaver, W. (1991). Technology Affordances, CHI 91
  Conference Proceedings, ACM Press, 1991, pp.79-84
  
• Heath, C. and Luff, P. (1991). Collaborative
  Activity and Technological design Task
  Coordination in London Underground Control Rooms.
  In Proceedings of the Second European Conference
  on Computer-Supported Cooperative Work, Kluwer,
  Dordrecht, 65-80.
• Norman, D. A. (1988). The psychology of everyday
  things. New York, NY Basic Books.Subsequently
  published under the title The design of everyday
  things.
• Shannon, C. E. (1948). A mathematical theory of
  communication, Bell System Technical Journal,
  vol. 27, pp. 379-423 and 623-656, July and
  October, 1948.
• Suchman, L.A. (1987). Plans and Situated Actions.
  Cambridge University Press, Cambridge.