Friday, July 1, 2011

Mental Models – How to track and analyse?


Cognitive scientists have argued that the mind constructs mental models as a result of perception, imagination and knowledge, and the comprehension of discourse.
Perception: Becoming aware of something by seeing, hearing or by using other senses.
Imagination: Forming new ideas, or images or concepts of external objects.
Knowledge: What is known perceptual experience and reasoning.
Comprehension of discourse: The action of understanding  something by written or spoken communication.
One notion is that analogies or metaphors function as tools of thoughts which help structure unfamiliar domain (Gentner and Gentner, 1983)
Example: (Analogies) Flowing waters simulates the flow of electricity and any other liquid substances.
Example: (Metaphor)
More is up/good is up
I’m feeling up. That boosted my spirits
Get up. Wake up. She rises early
There are several methods used to track mental models:
  • Novices and experts studies
  • Comparing users’ performance on a system
  • Protocol analysis
  • Field observation
  • Comparison across culture and historical comparison
  • Content analysis
  • Procedural mapping (Think aloud)
  • Card sort and many more…
These methods can be used together to support the findings.
Example: (like card sorts / novice and expert comparative study)
Barry R. Hill (Lebanon Valley College) realised a need for matching student mental models with experts in his case teachers so has to know that student are understanding the same way teachers are explaining any subject. He used card sort techniques with students and matched the grouping of ideas with the expert sorted ideas. This gave him better picture of how students are understood and interpret the information derived from the lectures.

Mental Models – Why to research?


One of the questions that arise while exploring mental model theory is why do we need to research on them and what is the use of in-depth knowledge of mental models? If they really exist how can we extract, represent and analyse it.
Gentner and Stevens (1983) in their book “Mental Models” have mentioned a simple yet interesting example which satisfy our question of why we need to understand mental models. 
Patrick Hayes’ (1979) extensive study on the behaviour of liquids. The understanding enables people to predict when a liquid will flow, stand still and fall from the surface. This theory would be useful any substance in liquid form and it would be helpful in understanding why operators of nuclear plants misinterpret their instruments. One of the chapter in the above mentioned book – “Flowing waters or teeming crowds: Mental models of electricity” by Gentner and Gentner (1983) have actually used similar metaphors to understand the behaviour of electricity.
When we talk about mental models in human computer interaction domain, Donald Norman has explained that:
“In interacting with the environment, with others, and with the artifacts of technology, people form internal, mental models of themselves and of the things with which they are interacting. These models provide predictive and explanatory power for understanding the interaction.“
Better understanding of the interaction leads to better system designs making peoples life easier while using any kind of devices to interfaces. He proposes that better conceptual model (model of the system) leads to easy learning and better performance while using a system. Easy Learning promotes increase in motivation to use the system and better performance enhances efficiency, accuracy and problem solving skills of a person.
To conclude the better our understanding (models) of the knowledge involved, the better we would be able to simulate, teach and test it

Mental Models – History


The term “Mental model” was first proposed by Scottish psychologist Kenneth Craik (1943) in his book, The Nature of Explanation. He believed that the mind constructs “small-scale models” of reality that it uses to anticipate events, to reason, and to underlie explanation. The concept was not explored by him much due to his untimely death the idea was left open for others to explore it.
According to Laird (2004), there were few precursors Lord Kelvin and Boltzmann who predicted the existence of mental models and coined some theories around it. Boltzmann wrote:
“The task of theory consists in constructing an image of external world that exists purely internally and must be our guiding star in thought and experiment; that is in completing, as it were, the thinking process and carrying out globally what on a small scale occurs within us whenever we form an idea”. (Boltzmann, 1899)
But the theory’s intellectual grandfather is Charles Sanders Pierce (Johnson-Laird, 2004). He first postulated (1896) in his theory about deduction that reasoning is a process by which a human “examines the state of things asserted in the premises, forms a diagram of that state of things, perceives in the parts of the diagram relations not explicitly mentioned in the premises, satisfies itself by mental experiments upon the diagram that these relations would always subsist, or at least would do so in a certain proportion of cases, and concludes their necessary, or probable, truth.”
In simple words, he explains that while we try to make sense of something or conclude about a situation in our daily activity we try to deduce two or more propositions (assumptions) which are called premises and form a diagram or visual images (model) and also try to identify connections between the entities (models). At the same time confirms the validity of the formed diagram (model/s) by performing mental experiments for a probable truth.
Kurtz explains mental models may be (1) An image, (2) A script, (3) A set of related mental models, (4) A controlled vocabulary, or (5) A set of assumptions. According to him a mental model may contain aspects of one or more of these types of models. A user may have an image of the look of an interface, a script of the process to be followed when completing a task, knowledge of the vocabulary the system uses, and assumptions about the behaviour of the system (Kurtz, 2004). The properties can co-occur: a photograph with verbal labels for its parts is iconic (diagram), indexical (connection) and symbolic (verbal description) (Johnson-Laird, 2004).
Many recent researchers have used mental models to explain aspects of thinking including problem solving, inductive learning, and human-machine interaction. The concept of mental theory became popular in cognitive science is largely due to Philip Johnson-Laird, who has used it extensively in explanations of deductive and other kinds of inference as well as many aspects of language understanding (Kurtz, 2004). Most of the literatures in mental models and thinking reasoning have been documented by him along with his associates.
Similarly Norman (1983) was one of the first attempts to create a terminology for a human-computer interaction theory of mental models where he introduced the idea of there being different models of a system (Kurtz, 2004). He suggested:
  1. Target system: A system user is using and learning.
  2. Conceptual model: Invented by teachers, designers as an accurate representation of the system.
  3. The system image: The impression system portrays to the users.
  4. Scientist’s conceptualisation of the mental model: A model of a model. In other words scientist’s assumption of user’s mental model.
References:
Johnson-Laird, P. N. 2004. The history of mental models. In: MANKTELOW, K. & CHUNG, M. C. (eds.)Psychology of Reasoning: Theoretical and Historical Perspectives. New York: Psychology Press.

Kurtz, A. 2004. Mental Models – A Theory Critique [Online]. The Open University. Available:http://mcs.open.ac.uk/yr258/ment_mod/ [Accessed].