Mental Models : Theory and Application in Human Factors JOHN R Mental Models : Theory and Application in Human Factors JOHN R. WILSON' and ANDREW RUTHERFORD, University of Nottingham, Nottingham, England 고려대학교 산업경영공학과 김보람

Mental Models : Theory and Application in Human Factors Introduction What are Mental Models? A Starting Point Different Approaches in Ergonomics and Psychology Mental Models and Theories of Knowledge Representation Pictures in the Mind? Use of Mental Models within Human Factors Conclusions

1.Introduction “Designing the machine to fit the human” The importance of employing knowledge of the users’ mental models in specifying the display

Is Mental Model Panacea? 1. Introduction Theory Mental Model theories developed and tested by cognitive psychologist Human factors literature on system design Cognitive ergonomics the application of psychological theories, models, and findings to problem of user interface design Is Mental Model Panacea? We don’t know if it has utility as an explanation of mind and behavior Difficulty to matching Application

2. What are Mental Models? A Starting Point Toffler “ Every person carries within his head a mental model of the world - a subjective representation of external reality” Wickens “hypothetical constructs that assist scientists in understanding behavior” “Users’ conceptual models” “Conceptualization” “Device model” “ Naive Theories” Norman ＆Young Designer’s conceptual model of the target system User’s mental model of the system

3. Different Approaches in Ergonomics and Psychology Ergonomists Say Rouse and Morris “The mechanism whereby humans are able to generate description of system purpose and form, explanations of system functioning and observed system states, and predictions of future system state” Rasmussen “Internal representations of environmental factors that determine the interrelationships among observable environmental data”

3. Different Approaches in Ergonomics and Psychology Psychologist Say Johnson Laird “enable individuals to make inferences and predictions, to understand phenomena, to decide what action to take and to control its execution, and above all to experience events by proxy”

3. Different Approaches in Ergonomics and Psychology 1. One source of confusion between the psychological and human factors notions of mental models lies in what the concept is employed to describe 2. Another source of confusion, at least with respect to Rasmussen’s account of mental models, is the claim that these are not psychological models but functional models Ergonomists Psychologists Human factors it is the product of such processes that is of concern Rasmussen intends to communicate the product The attempt is to describe mental processes Psychology is interested in both the function computed and the representation and algorithm (effective procedure) that compute the function 인간공학자와 심리학자 사이에 mental model의 viewpoint에 차이가 존재합니다. 이들 사이의 이런 Confusion은 첫째, 묘사하기 위해 어떤 개념을 적용시키느냐에 있다. 인간공학자는 인간의 knowledge의 처리(process)를 묘사하기 위해 시도하는 반면에 인간공학자는 Process에 대한 Product과의 mapping에 집중한다. 또 다른 이유로는, Mental model을 인간공학자들이 취할 때 하나의 심리학적 모델이 아닌, 기능적인 모델로 고려하기 때문에 이들 간의 혼란이 존재한다. 심리학자는 인간의 기능을 추정하는 표현이나 알고리즘에 관심을 가지는 반면, 인간공학자는 Product와 인간사이의 communication적인 측면에 관심을 가지고 있다.

4. Mental Models and Theories of Knowledge Representation Frame Scenario Script Schema Slot Input slots with appropriate information which From default value Frame of Restaurant Roles Props Customer Attendance Chef Food Menu Table

4. Mental Models and Theories of Knowledge Representation Frame Scenario Script Schema Schemata Mental model Mental model Schemata Mental models are regarded as the utilization of such information in a computationally dynamic manner schemata provide the procedures from which mental models are constructed Schemata are taken to be data structures in memory, which can be activated

“ ” 5. Pictures in Mind Internal representation a catchall term used to refer to some activity or state within the nervous system or a computer system that represents or is a token for some other entity Internal representation ⊃ Mental model Propositional representation Analogical representation Internal representation = Mental model “Mental models are frequently pictorial or image like” Visualization of system or more abstract data-processing models “ ” forms of behavior

6. Use of Mental Models Within Human factors They may be employed in general design guidance, as in such exhortations as "know the user's mental model“ To summon up the idea of a "picture in the mind" or an "envisionment“ To test the effects of different levels of training or task information on performance used to estimate the complexity of system use in order to enhance system design Programmed intermediaries encapsulating "knowledge“ of the human user In the explanation and description of behavior Mental model be employed as a tool in design

6. Use of Mental Models Within Human factors The displays of a process or system must be compatible with operators' internal representations of the system The displays themselves allow or determine that certain mental models be built up "interface design can influence the formation of a user's mental model“ "the designer is obliged to ensure the users have or construct an appropriate user model"

7. Conclusions The mental model notion is part of a continual theoretical development It is regarded as a step on the way to an explanation of mind and behavior Human factors community is often tempted (indeed needs) to go beyond this to obtain a tool to apply in systems or product design

7. Conclusions Human factors researchers now agreed on terminology and notion 1. Designer’s conceptual model - design’s representation of user 2. User’s conceptual model - user’s representation of the system 3. User’s mental model - descriptions of the user's internal representations which are informed by theories from psychology

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