Advanced HCI Effective Interaction Pt 1

1
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.

2
Explaining behaviour

• Well look at two ways of explaining behaviour
  that are relevant to interaction design (there
  are several more).
• Cognitive theory starting point is the
  individual and what goes on in the individuals
  head. (You did some of this in the second year
  HCI module).
• Activity theory starting point is the society,
  of which the individual is a part.
• Although these two ways of looking at interaction
  behaviour have their origins in different
  philosophical traditions they have some things in
  common as you might expect since they are
  directed at explaining the similar phenomena.

3
Explaining behaviour hard information
processing models of cognition

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

4
Explaining behaviour hard information
processing models of cognition

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

Modal Model of Memory (Based on Atkinson
Shiffrin, 1968)
5
Explaining behaviour softening the information
processing model of cognition
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.
6
A model of cognition (still essentially
information processing)

• 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
7
Cognitive explanations of human error

• Models of users should acknowledge people make
  errors
• Errors are part of normal human behaviour
• People make errors frequently
• Sometimes trivial
• Sometimes serious.
• You have to take this into account in design.
• If you design something assuming the user wont
  make errors then your model of the user is wrong
• Inevitable consequence is failure.
• But errors are bound up problem solving and with
  learning
• So not only is it good to design things so that
  errors are less likely
• It is also important to allow people to
  experiment, to play safely.

8
Cognitive model of error - Mistakes, slips (or
lapses)
I have an objective in carrying out an activity,
but due to some action on my part I dont get
the intended result
Error
Arise from experiential cognition I wasnt
concentrating on the action, I dont usually need
to. (Implies skilled performance is involved)
Arise from reflective cognition I reflected on
the problem, but I made a wrong decision.
9
Mistake or slip?

• Laura is editing some data on a spreadsheet.
• In the middle of doing one of the changes she has
  to call up another database to find some
  information.
• She wonders if she can copy several fields at
  once from the database and then paste them into
  the spreadsheet.
• She decides that this plan will work. When she
  pastes the cells into the spreadsheet all the new
  data is crowded into one cell and not distributed
  across several cells as you had expected.

10
Mistake or slip?

• Julie is writing her report.
• She reads through the 3000 word text and finds
  nothing wrong with the phrase the results of
  our tests were not as we had excepted.

11
Explaining behaviour ACTIVITY THEORY (start point
SOCIETY)

• offer the possibility of integrating the micro
  and macro concerns of those trying to improve
  our understanding of how to support work with
  technology.
• micro - the detailed minute-by-minute
  interaction between a user and a product (or
  system)
• macro - the wider social interaction with the
  product,
• The research problems which can be attacked more
  successfully with the use of the conceptual tools
  of Activity Theory, include the role of
  contextual factors in human computer interaction,
  the nature of cognitive artifacts, advantages and
  limitations of affordances, and user interface
  transparency, among others. (Bannon, 1997)
• Activity theory is optimistic about the
  potential for human development. (Nardi, 1998)
  does this explain why it hasnt found wider
  acceptance?.

12
Some Activity theory concepts People

• Activity refers to human activity only.
• All human activity takes place in a social and
  cultural context..
• Peoples activities are always directed to an
  outcome.
• You are what you do.
• People always use tools in their activities
  (tools might have a physical form might be mental
  constructs).

13
Some Activity theory concepts People and tools

• People always use tools in their activities
  (tools might have a physical form might be mental
  constructs).
• Tools shape the way people interact with the
  world.
• Tools have both an enabling and constraining
  function.
• All tools carry the history of their development
  in their design.
• If you design mediating tools for others (such as
  computer hardware or software), you are also
  responsible, in part, for the consciousness of
  others.

14
Some Activity theory concepts

• Differentiation between internal and external
  activities
• internal activities cannot be understood if they
  are analysed separately, in isolation from
  external activities, because there are mutual
  transformations between.
• Internalisation - transformation of external
  activities into internal ones
• Externalisation
• it is the constant transformation between
  external and internal that is the very basis of
  human cognition and activity. (Nardi, 1998).

15
Some Activity theory concepts

• Hierarchical scheme that describes the structure
  of an activity.
• Activity
• Action
• Operation
• Activities are motivated by human desires
• Actions can be operationalised, that is turned
  into operations.
• Operations can be conceptualized (Bodker, 1991)
  which means we think about what we are doing.

end
16
Some Activity theory concepts

• Breakdown situations
• experienced as tensions, problems or
  contradictions in how we understand the
  situation.
• This is the central dynamic of activity theory
  and, according to Nardi (1998), distinguishes it
  from superficially similar approaches such as
  distributed cognition. 

end
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Sources

• 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.
• 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.
• (not complete but see notes on web site)