Virtual University HumanComputer Interaction Lecture 11 The Psychology

Virtual University Human-Computer Interaction Lecture 11 The Psychology of Actions Imran Hussain University of Management and Technology (UMT) 1 Virtual University - Human Computer Interaction © Imran Hussain | UMT

In the Last Lecture • Learning • Thinking – Reasoning – Problem-solving • Skill acquisition 2 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Computer + Press Key + 3 Key Virtual University - Human Computer Interaction = CHAOS! © Imran Hussain | UMT

London Stock Exchange • London, 1986 • Inexperienced operator presses wrong key • Chaos at stock exchange • Systems staff work throughout night at stockbrokers Greenwell Montagu 4 Virtual University - Human Computer Interaction © Imran Hussain | UMT

In Today’s Lecture • Falsely Blaming • Mental Models – – – How mental models are formed? Examples Applying mental model Mental model development Mental model perception • Blaming the Wrong Cause • Reasons for self-blaming 5 Virtual University - Human Computer Interaction © Imran Hussain | UMT

In Today’s Lecture • Nature of Goals • Structure of Actions – – Cycle of action Stages of execution Stages of evaluation 7 Stages of an Action • Errors • Emotions 6 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Falsely Blaming the User • A person kept making mistakes when using a computer • Investigation showed others had same problem Why did you make that error? My fault User 7 Virtual University - Human Computer Interaction Didn’t you read the manual? Designer © Imran Hussain | UMT

People are Explanatory Creatures Interact with world Human tendency to form explanations 8 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Mental Model • Human (uses) understanding (conceptual model) of the way – Objects work – Events take place – People behave Mental Model Object Perceive User Designer Uses object 9 Conceptual Model Virtual University - Human Computer Interaction Design object © Imran Hussain | UMT

Defining Mental Models • Human (uses) understanding (conceptual model) of the way – Objects work – Events take place – People behave • Models people have of themselves, others, environment and things they interact with • Theories people have to explain what they have observed • Internal constructions (in the human mind) of some aspect of the external world • Knowledge of: – Learning how to use a system – Learning how the system works 10 Virtual University - Human Computer Interaction © Imran Hussain | UMT

How Are Mental Models Formed? • Mental model of a device is formed by interpreting perceived actions and visible structure 11 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Manipulating Mental Models How do things work ? develop apply Core set of abstractions Everyday Objects These could be correct or erroneous 12 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Manipulating Mental Models • Mental models are manipulated – Enabling prediction – Making inferences possible – This process is called ”fleshing out” or “running ” of the mental model Can involve both unconscious and conscious mental model 13 Virtual University - Human Computer Interaction © Imran Hussain | UMT

How Are Faulty Mental Models Formed? Object Fragmentary Evidence (incomplete info) Poor Understanding Naïve Psychology • Causes • Mechanisms • Relationships Mental Model 14 Virtual University - Human Computer Interaction Faulty © Imran Hussain | UMT

Effect of Faulty Mental Models If design of an object does not give information (external info) about how it works Faulty Mental Model Frustration 15 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Effect of Faulty Mental Models • Computer screen freezes bash keyboard • TV not working bang TV top 16 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Mental Model - Examples • Thermostat used to control temperature (oven, room, AC) • Folk (name) theories about thermostat – Timer theory • Thermostat controls relative properties of time that device stays on. • Setting – Midway : device is on about half rime – All way : device is on full time – Valve theory • Thermostat controls how much heat or cold comes out of device • Setting – Midway : half cooling – All way : full cooling • Reality about thermostat – Thermostat is On-Off switch 17 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Mental Model - Examples • Electricity and electrical appliances • TV • Car brakes • Spreadsheet – User : sheet that scrolls with cells containing information – Reality : data structure of values, with pointers between them, from which the program synthesizes a new image to display in real-time • Screen is the heart of computer (not CPU) – Perception by normal user 18 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Evolution of Mental Models • More greater use of system, the more their mental model develops • Example: TV – Engineers Mental model : “deep” • So they can fix – Average citizen’s mental model : “shallow ” • So they cannot fix, only use 19 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Mental Models and Perception perform Action (A) Perceive Causal Relationship (does not exist!) see Result (R) 20 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Mental Models and Perception - Example • Connect to internet to see website ‘x’ [Action] • Suddenly computer goes dead [Result] Perceive: Action 21 Virtual University - Human Computer Interaction Result © Imran Hussain | UMT

Using a Complex Device La. . !! How am I stupid! 22 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Using a Complex Device How am I stupidam I How stupid How am I stupid ! 23 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Blaming the Wrong Cause • When things go wrong – Own misfortune blame Environment – Other’s misfortune blame Personalities • When things go right – Own fortune – Other’s fortune 24 Credit Virtual University - Human Computer Interaction Oneself Environment © Imran Hussain | UMT

Reasons for Self-blame • Learned Helplessness – Failure to perform a task numerous times feeling of helplessness Depression • Taught Helplessness – Lack of understanding at one stage hinders progress at another stage Fail at A task Blame Self Believe can’t do Some task next Time round Do not Try Self –fulfilling prophecy 25 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Nature of Human Thought and Explanation • Not easy to see where blame should be placed – 3 -Mile Island Accident – Lockheed L-1011 Flight 26 Virtual University - Human Computer Interaction © Imran Hussain | UMT

3 -Mile Island Nuclear Power Plant 28 March 1979, Pennsylvania, USA Control Panel Push button Valve 27 Virtual University - Human Computer Interaction Nuclear Core © Imran Hussain | UMT

3 -Mile Island Nuclear Power Plant Normal State Button (Not Pushed) Button light (OFF) Valve Open Excess water escapes From nuclear core Accident Action State Button Pushed Button light (ON) Valve Closes Valve Open Excess water escapes From nuclear core Operator knew that Valve was leaky but Thought it wouldn’t affect main operation 28 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Lockheed L-1011 Flight Miami, Florida Nassau, Bahamas 110 miles 29 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Lockheed L-1011 Flight Engine 1 Engine 2 Engine 3 Low oil pressure light Pilot Engine turned off 8 minute later Oil Pressure = 0 Oil Quantity = 0 Pilots concluded = Not likely that all 3 should fail 30 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Nature of Goals • For everyday life, goal and intentions are not well-specified: Opportunistic vs. Planned • Shop • Friend • Library • Visit a website • Using a software feature 31 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Structure of an Action Execute Evaluate Goal 32 (Use Intentions - specific) (Vague) Virtual University - Human Computer Interaction © Imran Hussain | UMT

Structure of an Action • Example – Nighttime sitting in chair, reading a book. Need light Goal (Some thing to be achieved) Get more Light translate Intention (Specific action taken to get the goal) Push switch button to ON lamp translate • Move Body • Stretch • Extend finger 33 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Action Cycle Goals What we want to happen Execution Evaluation What we do to The world Comparing what Happened with what We wanted to happen THE WORLD 34 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Stages of Execution Goals An intention to act So as to achieve the goal The actual sequence of actions That we plan to do The physical execution of That action sequence THE WORLD 35 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Stages of Evaluation Goals Evaluation of the interpretations With what we expected to happen Interpreting the perception according to our expectations Perceiving the state of the world THE WORLD 36 Virtual University - Human Computer Interaction © Imran Hussain | UMT

7 Stages of Action Goals Intention to act Evaluation of the Interpretations sequence of actions Interpreting the perception execution of The action sequence Perceiving the state of the world THE WORLD 37 Virtual University - Human Computer Interaction © Imran Hussain | UMT

“To Err is Human” 38 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Errors • People routinely make mistakes – E. g. , corrections made during conversation – Devices do not have tolerance for things that go wrong – Push the wrong button 39 Virtual University - Human Computer Interaction chaos © Imran Hussain | UMT

Errors • Developers should design for errors – – – 40 Must assume errors will occur Minimize errors Errors should be easy to detect Effects of errors should be minimal Effects of errors should be reversible Virtual University - Human Computer Interaction © Imran Hussain | UMT

Errors Slips Automatic behavior 41 Virtual University - Human Computer Interaction Mistakes Conscious deliberations © Imran Hussain | UMT

Errors are Based On Goals Correct Goal Wrong Execution (due to lack of attention) 42 Incorrect Goal Wrong/Right Execution Slip Mistake (easy to discover) (harder to discover) Virtual University - Human Computer Interaction © Imran Hussain | UMT

Errors are Based On Goals • Most everyday errors are slips • Study of slips – Study of the psychology of everyday errors – “Psychopathology of everyday life” – Freud – Example • You went to fetch a book, but fetched a pen instead • Slips show up in skilled behavior • We can do more than one thing if we do them automatically 43 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Precise Behavior from Imprecise Knowledge • Differentiating between coins 44 Virtual University - Human Computer Interaction © Imran Hussain | UMT

Word of Advice • Don’t press the wrong key! 45 Virtual University - Human Computer Interaction © Imran Hussain | UMT