Cognition

1. Cognition Representation and Processing Categorization Problem Solving Decision Making Uncertainty, Heuristics, and Biases

2. Cognition is the activity of mind • The act of picking up information • Both from the world and from memory • and • The processing of that information • Transforming information into action in the pursuit of a goal

3. Perceiving Understanding Remembering Concept forming Categorizing Problem solving Decision making Judgment Communicating Activities of Mind This list is NOT complete THINKING

4. Frank Miller The magic number 7 ± 2 An intrinsic limitation of human short term memory The first paper by a psychologist to discuss the workings of mind since the dawn of behaviorism in 1913 Herbert Simon Humans do not optimize when making decisions, rather We “satisfice” We take the first available satisfactory alternative The first paper by an economist to discuss actual decision behavior 1957

5. Noam Chomsky Humans are born knowing a generative grammar that enables us to learn and speak languages flawlessly without any teaching These three men led the charge to overturn the behaviorists’ prohibition against discussing the activity of mind. They freed psychology to discuss not only inputs and behavior but also the processes that transform inputs into behavior. 1959

6. The dawn of computing • The 50’s also saw the emergence of the digital, serial computer • The scientists and engineers working with computers soon realized that these machines could do much more than calculate • Given data (input) and an instruction set (a program), a computer could be made to “reason” • In the early 60s Herbert Simon and others began to claim that the digital serial computer was an apt analogy for the activities of mind

7. Computer Input The instruction set Output Human Information from the environment or from memory Information processing, thinking Behavior, action, activities of mind The computer analogy

8. The claim:Only three things are needed • Representation • The mind needs to represent the world (local environment) and items in it • Processing • The mind needs a plan of action that operates on the representations • Goals • The mind needs to direct its actions toward goals

9. The digital computer uses binary numbers to represent things in the world E.g., 10010100101 The human mind uses symbols to represent things in the world E.g., “dog” The representation analogy

10. Processing • The symbols that represent (items in) the world need to be processed, to be transformed into new symbols • The act of transforming symbols is the activity of mind

11. Goals • This system for transforming symbols does not act randomly • It is goal-directed • Goals determine the course of behavior

12. Implications of the computer analogy • All thinking can be reduced to a series of processes that transform information into behavior • Thinking IS information processing • As a result, • Cognitive Psychology is often called • Information Processing Psychology

13. A typical cognitive model Info. Processing More processing Still more processing Behavior

14. Categorization An example of an activity of mind

15. Example Category: Bird Dimensions: Has wings Flies through the air Lays eggs etc. Categorization,An activity of mind Categories are representations that organize bundles of information along dimensions of similarity

16. Categories are culturally shared • Everyone within a particular culture is highly likely to apply the same categories for the same information • If it flies and lays eggs, it’s a bird (until shown otherwise) • Many categories are shared across cultures

17. ‘Is A’ link Fish Bird Representing categories • Categories typically form hierarchies consisting of concepts and “is a” links Animal

18. ‘Is A’ link Animal Fish Bird Canary Ostrich Shark Salmon Hierarchies • Categories typically form hierarchies consisting of concepts and “is a” links and other hierarchies

19. Downwardly inheritable properties ‘Is A’ link eats moves breathes Animal swims flies fins wings gills sings Fish Bird yellow can’t fly scary yummy Canary Ostrich Shark Salmon How Cognitive Psychology Views Hierarchies

20. Prototypes • The best fitting member of a category • Inherits all properties of the category and adds no exceptions • Recognition of a prototype as a member of its category is relatively quick and easy • Example: • Robin - fast • Emu - slow

21. Problem Solving An example of an activity of mind

22. Familiar examples of problems • Losing weight • Finding a good roommate • Making a silk purse from a sow’s ear • When I grow up I wanna be a ...

23. GAP = The Problem How cognitive psychology views Problem Solving • Any and all problems can be characterized as the gap between an initial state and a goal state • The initial state = where you’re at • The goal state = where you want to be Initial State Goal State

24. GAP = The Problem A Sample Problem • Any and all problems can be characterized as the gap between an initial state and a goal state • The initial state = where you’re at • The goal state = where you want to be 3rd String Starter

25. Intermediate states • Within the gap are any number of intermediate states • Some are steps along the way to the goal • Others are blind alleys • Some are garden paths Tennis 2nd String 3rd String Starter Special Teams

26. Problem Space • The full collection of intermediate states is called the Problem Space • The problem space specifies all possible paths from the initial state to the goal state ... Tennis ... ... ... 2nd String ... 3rd String ... Starter ... ... ... Special Teams ... ... ...

27. ... Intermediate States Solving a problem involves • Moving from your initial state via some intermediate states to your goal state • = • Moving through the problem space Goal State Initial State

28. Tennis 2nd String Special Teams Solving a problem involves • Moving from your initial state via some intermediate states to your goal state • = • Moving through the problem space 3rd String Starter

29. Traversing the problem space • To do this you have to represent • (1) the initial state, • (2) some (all) intermediate states, • (3) the goal state, and • (4) potential Operators for moving from state to state • Operators: • Processes to apply to the representations

30. Sample Problem • The 2-disk Tower of Hanoi • There are three pegs • and two disks, • a large disk and a small disk • The disks slip onto the pegs

31. Initial State Sample Problem • The 2-disk Tower of Hanoi • There are three pegs • and two disks, • a large disk and a small disk • Initial state of the game: • Both disks are on one of the pegs

32. Initial State Goal State Sample Problem • The 2-disk Tower of Hanoi • There are three pegs • and two disks, • a large disk and a small disk • Goal state of the game: • Both disks are on another peg

33. Initial State Goal State Sample Problem • The 2-disk Tower of Hanoi • There are three pegs • and two disks, • a large disk and a small disk • Rules: • 1) You can move only one disk at a time • 2) The large disk cannot be placed on top of the small disk

34. Initial State How to start solving the problem • Represent the initial and intermediate states and the moves • Make a diagram that REPRESENTS the initial state of pegs and disks

35. Represent the initial and intermediate states and the moves Make a diagram that REPRESENTS the initial state of pegs and disks Make a second diagram that REPRESENTS the next state Use arrows to REPRESENT the moves Initial State How to continue Next State

36. Goal State Solving the problem • Continue until the next state is the goal state Current State Next State

37. These diagrams are examples of physical representations Cognitive Y assumes that the act of thinking about the problem works on mental representations of some sort Initial State Representation Next State

38. Moving the small disk from peg1 to peg2 is an operator in the problem space The thinking of it and the doing of it are examples of information processing Processing (operators) Initial State Next State

39. Goals are in the world but they are also represented in the mind Thinking operates on the symbols in your mind Goal State Goals

40. Problem solving involves • Representing • 1) the initial state, • 2) the goal state, and • 3) some of the intermediate states • Representing and applying the • the operators that afford moving from the initial state to the goal state

41. Decision Making An example of an activity of mind

42. A decision is a CHOICE between (among) outcomes (options, payoffs) Examples Coke or Pepsi? Love or money? Safety or adventure? Kansas or Sweden? A problem exists whenever there is a GAP between the problem solver’s current state and goal state All decisions are problems, but not all problems are decisions Decisions ≠ Problems

43. Example of a Decision • You are looking for an apartment for next year • You are considering 4 different apartments that vary along 4 dimensions • Price • Proximity to campus • Alarm system • Parking

44. Which apartment do you prefer? Apartment A, B, C, or D?

45. Which apartment do you prefer? Apartment A, B, C, or D?

46. Which apartment do you prefer? Apartment A, B, C, or D?

47. Which apartment do you prefer? Apartment A, B, C, or D?

48. The decision itself is an outcome Good decision making Seeks to reduce uncertainty Adds constraints Prioritizes information Looks for complete information Decision making is a process

49. A continuum of uncertainty • Certainty • Risk • Ambiguity

50. Certainty • This is a representation of a container filled with 90 marbles • 30 red, 30 blue, 30 yellow • The bottom row represents the $ you get if you select (while blindfolded) a marble of that color