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The User

Lecture 5

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Overview of Lecture

•Introduce final cognitive process – learning

•Interaction of cognitive processes

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H u m an P rocesses

P ercep tion A tten tion M em ory L earn in g

Human Considerations

Cognitive Processes - Learning

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Learning

Techniques toGuide Learning

Human Considerations

Cognitive Processes - Learning

Approaches to Learning

Learning Through Analogy

Learning Through Trial-and-Error

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Cognitive Processes - Learning•The success of any computer system depends on the extent to which the users can learn and use the system

•The learning process is complicated, involving a number of independent factors

•Understanding the basics of this process is important:

•need to understand the difficulties in learning to use a computer system•know the different strategies people use when learning•be able to implement methods that aid the user in learning

Human Considerations

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Cognitive Processes - Learning

A General Observance of UsersA General Observance of Users

•When users encounter a computer system for the first time, their most common reaction is one of fear:

•Their only assistance may be a large manual•Series of ordered explanations •Step-by-step exercises

•Learner feels overloaded with information and frustrated

•However, when for example someone is learning to drive, they tend to be excited at the prospect:

•People usually learn to drive through doing and verbal instruction

Human Considerations

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Cognitive Processes - Learning

•Assumption that having read something in the manual, users can immediately match it to what is happening and the interface, is generally inaccurate

•Often it is not the instructions that help a user understand a device, it is the device that helps the user understand the instructions

•In order to bridge the gap between the users and the system, improving the instructions and on-line help can go a long way

•However we must also understand the way in which users normally learn

Human Considerations

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Cognitive Processes - Learning

Problems users have with manuals:Problems users have with manuals:•It has be observed that the majority of users tend to ‘jump the gun’ skip

•Those that do follow the manual end up committing a number of small errors that often resulted in them being side-tracked

•Users are also reluctant to learn new methods from manuals, they continue to use procedures they already know which may be less effective

On the basis of these and other findings, Mack et al. have classified some major problems confronting users when trying to learn

Human Considerations

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Cognitive Processes - Learning

•Learning is difficult

•experience frustration

•learning takes longer than expected

•Learners lack basic knowledge

•naïve about computers

•Learners make ad hoc interpretations

•construct incorrect interpretations

•interpretations can prevent them from seeing that they have a problem

Human Considerations

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Cognitive Processes - Learning

•Learners generalise from what they know•e.g. text editors work like typewriters

•Learners have trouble following directions•Don’t always read or follow directions•Do not always understand directions when they try

•Problems interact•Don’t understand that one problem can create another

Human Considerations

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Cognitive Processes - Learning

•Interface features may not be obvious•may be confused by feedback and results

•Help facilities do not always help•Do not always know what to ask for•Help information is not always focused on the learners specific problem

Human Considerations

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Cognitive Processes - Learning

•There are two main approaches that users use when learning new computer systems

Learning through

AnalogyTrial andError

Human Considerations

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Cognitive Processes - Learning

Learning through AnalogyLearning through Analogy

•Two theories are used in this approach (introduced in “Cognitive Frameworks”) :

•Mental Models•Metaphors

Human Considerations

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Cognitive Processes - Learning

What is the metaphor used here?

Human Considerations

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Cognitive Processes - Learning

What is the metaphor used here?

Human Considerations

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Cognitive Processes - Learning

Guidelines to Creating Mental Models & MetaphorsGuidelines to Creating Mental Models & Metaphors

•Provide design consistency•greatly reduces the number of models to be learned

•Draw physical analogies•replicate the environment that has become familiar and well-known

•Comply with expectations and stereotypes•avoid new and unfamiliar associations

•Provide action-response compatibility•e.g. command names should reflect their purpose

•Provide necessary and proper feedback•efficient learning of the mental model will not occur unless feedback is provided

Human Considerations

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Cognitive Processes - LearningLearning through Trial and ErrorLearning through Trial and Error

•We always make mistakes learning a new skill

•Feedback from making errors can help us to learn and understand an activity

•Users of computer systems are often scared of making errors

•Anticipation of errors may hinder a users interaction with a system

•Must provide safeguards but also good feedback

Human Considerations

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Cognitive Processes - Learning

•There are two categories of errors

•MistakesMistakes – •Incorrect mental model, incorrect action is taken based on an incorrect decision•Occur intentionally

•SlipsSlips – •unintentional errors•Skilled behaviour

Human Considerations

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Slips

capturefrequently done

activity capturesthe action

descriptioncorrect action,wrong object

data-drivenunconsciousprocessing ofexternal data

associative-activationinternal thoughts

interfere with currenttask

loss-of-activationforgot something

mid-flow of activity

modethinking in one state

but actually in another

Human Considerations

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Cognitive Processes - Learning

Human Considerations

Error Prevention GuidelinesError Prevention Guidelines

•Use good coding techniques (color, style)

•Maximise recognition, minimize recall

•Minimise need for typing

•Allow reconsideration of action by user (e.g., removing file from trash)

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Cognitive Processes - Learning

Human Considerations

Error Prevention GuidelinesError Prevention Guidelines•Provide appropriate type of response

•Prevent user from continuing

•Warn user an unusual situation is occurring

•Self-correct - spell-check correction

•System opens dialog with user - go into debugger on run-time crash

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Cognitive Processes - Learning

Human Considerations

Error Correction GuidelinesError Correction Guidelines•Provide undo function

•Provide cancel function from operations in progress

•Require confirmation for drastic, destructive commands

•Provide some intelligence•Guess what they wanted to do

•Provide quick access to context-sensitive help

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Three main commandments for aiding user learning

Mental Models

Metaphors

Errors

Human Considerations

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Cognitive Processes - Learning

Techniques to guide learning:

•Design interfaces that

•encourage exploration

•constrain and guide users to select appropriate action

•prevent/correct errors

•Dynamically link representations and abstractions that need to be learned

•Useful feedback should be provided

•Maximise recognition, minimise recall

Human Considerations

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Cognitive Processes Interactive Processes

Human Considerations

Adapted from Wickens' Human Information Processing Model

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Cognitive Processes Interactive Processes

Human Considerations

Cognitive Process Guidelines

AttentionAttention

PerceptionPerception LearningLearning

MemoryMemory

Attention is aided by perception

Attention enhanceslearning

Learning enhancesmemory

Perception requiresmemory

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Summary of User Considerations

References

•Nature/type of userNature/type of user

•Human considerations in developing a user Human considerations in developing a user interfacesinterfaces

•Cognitive Frameworks•Cognitive Processes

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Summary of User Considerations

Nature of User

User GroupsUser Groups

Computer skillsComputer skills& knowledge& knowledge

Age Age

DisabilitiesDisabilities CulturalCultural

•Discretionary

•Non-discretionary

•Novice

•Expert

•Physically disabled

•Cognitively

disabled

•Ageing user

•Young user

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CognitiveCognitiveProcessesProcesses

Human Considerations

Summary of User Considerations

Perception Attention Memory LearningClasses of Visual Perception Theory•Constructivism•Ecological

Techniques to guide perception

•Basic forms of attention

•Multi-tasking & interruptions

•Automatic processing

•Techniques to guide attention

•Memory categories

•LoP Theory

•Recognition vs Recall

•Techniques to guide memory

•Approaches to learning •Learning through

Analogy

•Learning through

Trial-and-Error

•Techniques to guide learning

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Terms of Reference• Norman, D. (1990) The Design of Everyday Things

• Preece, J. et al. (2002) Interaction Design

• Shneiderman, B. & Plaisant, C. (2005) Designing the User Interface

• Benyon, D. et al (2005) Designing Interactive Systems

• Wickens, C.D. (1992) Engineering Psychology and Human Performance

• Mack, R. (1983) Learning to use word processors: problems and prospects

• FAA (..) FAA Human Factors

• http://www.ted.com/index.php/talks/view/id/7 (video)

• http://www.ted.com/index.php/talks/al_seckel_says_our_brains_are_mis_wired.html (video)

References