1 The User Lecture 5

2 Overview of Lecture Introduce final cognitive process – learning Interaction of cognitive processes

3 Human Considerations Cognitive Processes - Learning

4 Learning Techniques to Guide Learning Human Considerations Cognitive Processes - Learning Approaches to Learning Through Analogy Learning Through Trial-and-Error

5 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

6 Cognitive Processes - Learning A 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

7 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

8 Cognitive Processes - Learning 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

9 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

10 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

11 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

12 Cognitive Processes - Learning There are two main approaches that users use when learning new computer systems Learning through Analogy Trial and Error Human Considerations

13 Cognitive Processes - Learning Learning through Analogy Two theories are used in this approach (introduced in “Cognitive Frameworks”) : Mental Models Metaphors Human Considerations

14 Cognitive Processes - Learning What is the metaphor used here? Human Considerations

15 Cognitive Processes - Learning What is the metaphor used here? Human Considerations

16 Cognitive Processes - Learning Guidelines 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

17 Cognitive Processes - Learning Learning 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

18 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

19 Slips capture frequently done activity captures the action description correct action, wrong object data-driven unconscious processing of external data associative-activation internal thoughts interfere with current task loss-of-activation forgot something mid-flow of activity mode thinking in one state but actually in another Human Considerations

20 Cognitive Processes - Learning Human Considerations Error 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)

21 Cognitive Processes - Learning Human Considerations Error 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

22 Cognitive Processes - Learning Human Considerations Error 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

23 Three main commandments for aiding user learning Mental Models Metaphors Errors Human Considerations

24 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

25 Cognitive Processes Interactive Processes Human Considerations Adapted from Wickens' Human Information Processing Model

26 Cognitive Processes Interactive Processes Human Considerations Cognitive Process Guidelines Attention PerceptionLearning Memory Attention is aided by perception Attention enhances learning Learning enhances memory Perception requires memory

27 Summary of User Considerations References Nature/type of userNature/type of user Human considerations in developing a user interfacesHuman considerations in developing a user interfaces Cognitive Frameworks Cognitive Processes

28 Summary of User Considerations Nature of User User Groups Computer skills & knowledge Age Age DisabilitiesCultural Discretionary Non-discretionary Novice Expert Physically disabled Cognitively disabled Ageing user Young user

29 CognitiveProcesses Human Considerations Summary of User Considerations PerceptionAttentionMemoryLearning Classes 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

30 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 (video) mis_wired.html (video) mis_wired.html References