[HCI2.0] Week 02. Users' Mental Models
Transcript of [HCI2.0] Week 02. Users' Mental Models
Lecture 2
Users’ Mental Models
Human Computer Interaction / COG3103, 2015 Fall Class hours : Tue 1-3 pm/Thurs 12-1 pm 8th September
From Usability to User Experience
Lecture #2 COG_Human Computer Interaction 2
Figure 1-2 User experience occurs within interaction and usage context
User’s Mental Models : The Very Ideas
• Book
– Stephen J. Payne, “User’s Mental Models : The Very Ideas” in John M.
Carroll, (2003) HCI Models, Theories, and Frameworks : Toward a
Multidisciplinary Science, CA : Morgan Kaufmann Publishers, pp. 135-156.
COG_Human Computer Interaction 3 Lecture #2
Design Philosophy
• Herb Simon:
“Engineers are not the only professional designers. Everyone
designs who devises courses of action aimed at changing existing
situations into preferred ones.
The intellectual activity that produces material artefacts is no different
fundamentally from the one that prescribes remedies for a sick patient or the one
that devises a new sales plan for a company or a social welfare policy for a state.”
– Herbert A. Simon, The Sciences of the Artificial, 1969 (p.129 of 1981 MIT press 2nd
edition)
COG_Human Computer Interaction 4 Lecture #2
Intro
COG_Human Computer Interaction 5
Figure 1 (adapted from Norman (1988) p. 16): The problem of ensuring that the user's mental model corresponds to the designer's model arises because the designer does not talk directly with the user. The designer can only talk to the user through the "system image" - the designer's materialised mental model. The system image is, like a text, open to interpretation.
Lecture #2
Users
• Mental Models
– User’s knowledge about the system they use.
• Bounded Rationality (Simon, 1955)
– People often have to act too quickly to allow full consideration of all their relevant
knowledge – they do the best they can to achieve their goals according to the
knowledge they can bring to mind, and the inferences that knowledge supports, in the
time allowed.
– “Bounded rationality” : rationality that is bounded by the environmental constraints on
their performance, interacting with their limits on access to knowledge and the limits on
their performance, interacting with their limits on access to knowledge and the limits on
their ability to process relevant information.
COG_Human Computer Interaction 6 Lecture #2
Mental Models
• Idea 1. Mental Content vs. Cognitive Architecture : Mental Models as
Theories
– Bounded Rationality : the general limits of the human information-processing
system – the constrains on attention, retrieval, and processing.
– Human information-processing architecture : theories of the structure of the
mind.
– Contents of the mind : what do people believe about an aspect of the world,
what is the relation between these beliefs and reality, and how do the beliefs
affect their behavior?
COG_Human Computer Interaction 7 Lecture #2
Cognitive Architecture
COG_Human Computer Interaction 8
A model of the user based on an information processing metaphor
Lecture #2
Mental Models
• Idea 2. Models vs. Methods : Mental Models as Problem Spaces
– Mental models of machines can provide a problem space that allows more
elaborate encoding of remembered methods, and in which novice or expert
problem solvers can search for new methods to achieve tasks.
– Stepping through a sequence of states in some mental models of a machine, is
often called “mental simulation” in the mental-models literature, and the kind
of model that allows simulation is often called “surrogate”
– Reasoning is performed by sequential application of completely domain-
specific rules and thus is knowledge bounded rather than architecture
bounded.
COG_Human Computer Interaction 9 Lecture #2
Mental Models
• Idea 3. Models vs. Descriptions : Mental Models as Homeomorphisms
– Mental models are a special kind of representation, sometimes called an
analog representation – one that shares the structure of the world it
represents.
– Example
• The spoon is to the left of the fork spoon fork
• The knife is to the left of the spoon knife spoon fork
– Such a model allows deductive inferences to be “read off”
COG_Human Computer Interaction 10 Lecture #2
Swankolab
COG_Human Computer Interaction 11 Lecture #2
Mental Models
• Idea 4. Models of Representations : Mental Models Can Be Derived
from Language, Perception, or Imagination
– Mental models can be constructed by processing language, but the same
models might also, in principle, have been constructed through
interaction with and perception of the world. Therefore a mental model
provides a way of mapping language to perception.
COG_Human Computer Interaction 12 Lecture #2
Mental Models
• Idea 5. Mental Representations of Representational Artifacts
– The yoked state space hypothesis(Payne, Squibb, & Howes, 1990)
• To construct a conceptual model of a device, the user must conceptualize the
device's representation of the task domain. This knowledge can be
represented by three components: a device-based problem space, which
specifies the ontology of the device in terms of the objects that can be
manipulated and their interrelations, plus the operators that perform the
manipulations; a goal space, which represents the objects in terms of which
user's goals are expressed; and a semantic mapping, which determines
how goal space objects are represented in the device space.
COG_Human Computer Interaction 13 Lecture #2
Social Networking Space
Lecture #2 COG_Human Computer Interaction 14
Mental Models
• Idea 6. Mental Models as Computationally Equivalent to External
Representations
– If structure-sharing is taken to be an important property of mental models,
then a mental model derived from text shares the structure of the situation,
not of the text.
– However, it is not clear that this distinction extends to mental models
derived from “reading” other representational artifacts, such as maps, or
diagrams.
COG_Human Computer Interaction 15 Lecture #2
Homework
Lecture #2 COG_Human Computer Interaction 16
Submission Due : 11: 59 pm Sun. 13th Sept.
Video in a time capsule
Your Blog Post #3 - Title “Message to myself in Future” - Edit it in the length of 30 seconds. - Share the vimeo(or youtube) link on your blog