Exam 3 Flashcards
Well- and Ill-Defined Problems:
What is a problem? What are its 3 components?
- problem: a situation without an immediately apparent standard or routine way of reaching a goal
- 3 components:
1. ) goal state (what you’re working towards)
2. ) initial state (info you have at start of problem)
3. ) operators (action you can take to move from initial to goal state)
Well- and Ill-Defined Problems:
What is the difference between a well-defined and an ill-defined problem?
- well-defined: all 3 components are known
- ill-defined: at least one component is undefined/not known; possibly more difficult to solve
Well- and Ill-Defined Problems:
What are Goel’s four stages of ill-defined problem-solving?
- 1.) problem scoping - what problem entails; use knowledge you have to study problem statement
- 2.) preliminary solution generation - trying to figure out how you’re going to go about finding a solution, path to solution; “lateral transformation”
- 3.) refinement - how it would look if you took a particular path; “vertical transformation”
- 4.) detailing of solutions - final commitment to one path/solution
Well- and Ill-Defined Problems:
What is the difference between a lateral transformation and a vertical transformation through problem space, according to Goel?
- vertical: look down a path to see what would happen next, what steps
- horizontal: comparing choices/options at each move
Well- and Ill-Defined Problems:
What role does the prefrontal cortex play in solving well- vs. ill-defined problems, according to Goel?
- location where the problem mainly occurs
- hemisphere difference in how approach the problem:
- left hem. damage: impairs well-defined problem solving
- right hem. damage: impairs ill-defined problem solving
Well- and Ill-Defined Problems:
What is a problem space? How is it constructed? Describe the tic-tac-toe example
- problem space: visualizing the solving of a problem
- depict stages of a solved problem or turns in a game as a tree
- limited by STM (not enough memory for all possible moves)
- tic-tac-toe: ex. first move of X has 9 choices (branches), second move (next level) is O and has 8 choices
Problem-Solving Strategies and Heuristics:
What is an algorithm? What is a heuristic? What are the advantages/disadvantages of them?
- algorithm: set of procedures that you follow to solve a problem (ex. long division, recipe)
- advantage of algorithm is if you follow it exactly you won’t make a mistake
- heuristic: short-cut for how to do something; help you get to solution more quickly
- advantage of heuristic is it’s quick if you don’t need an exact answer
Problem-Solving Strategies and Heuristics:
What are the heuristics of random guess?
- provides shortcut, gets you kind of closer to the answer
Problem-Solving Strategies and Heuristics:
What are the heuristics of hill-climbing? Discuss how the Rubik’s cube and hobbits and orc problem relate to this type of heuristic
- pick next move to make it look like you’re getting closer to the solution/goal state
- sometimes looks like you’re moving closer but you may be moving further away from the solution
- Rubik’s cube problem utilizes this heuristic
- Hobbits and orcs problem: people have difficulty making a necessary backward move bc it looks like it’s getting them further away from the solution
Problem-Solving Strategies and Heuristics:
What are the heuristics of means-end analysis? How does it relate to the Tower of Hanoi task?
- breaking a big problem down into smaller problems
- Tower of Hanoi - focus on getting the next ring in goal state
- efficient to deal with large problems
- first choice may be significant for next moves but likely don’t realize it
Problem-Solving Strategies and Heuristics:
What is functional fixedness? What are the two classic examples of this?
- functional fixedness: fixated on object’s typical use and cannot see how to use it differently in nontraditional fashion
- ex. Two String Problem - have to hold two strings but they aren’t long enough, have to use pliers to make a pendulum
- ex. Candle on the Wall - have to mount a candle onto the wall and only have the candle and a box of tacks to do so
Problem-Solving Strategies and Heuristics:
According to Simon and Newell what are the basic characteristics of the human information-processing system?
- it’s serial (deals with one thing at a time)
- elementary processes take less than one second
- inputs and outputs are stored in limited STM
- LTM has a higher capacity but it’s slower to store info
Problem-Solving Strategies and Heuristics:
Could a computer model solve problems the same exact way that humans do?
- No
- humans are limited by short-term memory
Problem-Solving Strategies and Heuristics:
What is the difference between a “scan and search” strategy and a “progressive deepening strategy”? Which one do people typically use and why?
- “scan and search” - identify most promising node and look ahead before committing to solutions; helps to avoid problems; most efficient strategy
- “progressive deepening” - look for the shorter path to take through a space, may not look at all nodes or branches
- ppl use progressive deepening more due to limited STM bc can’t remember all possible outcomes in scan and search
Problem-Solving Strategies and Heuristics:
What info is used to define a problem space?
- task instructions
- previous experience with similar tasks
- programs in LTM for such tasks
- programs in LTM to construct problem spaces
- information learned while solving the problem
Problem-Solving Applications:
Describe what the Carraher at al study did and found. What mistakes did the children make?
- explore how child street vendors did math on the streets
- informal task: researchers asked prices on the street in “natural” environment
- formal task: formal test of mathematical procedures, operation problems, word problems
- performance overall on formal task wasn’t as good as informal; however did better with word problems then the straight up math problems
- mistakes: swapped order of operations, incorrect operator, didn’t use operator at all
Problem-Solving Applications:
What does it mean to reason by analogy when it comes to problem solving? How does the Gick and Holyoak study show this?
- reason by analogy: make connections/adapt or modify previous solution to current situation
- Gick and Holyoak: given problem with solution (fortress/dictator) and given another problem without solution (tumor/doctor)
- see similarities between the two problems’ elements and adapt existing solution to fulfill current needs
Problem-Solving Applications:
Describe the two examples of real-world problem solving discussed in class
- ex. adapt plastic bottles to act like a light bulb
- ex. nail polish that detects some date-rape drugs
Conditional Reasoning:
What is the difference between conditional, deductive, and inductive reasoning?
- conditional: given conditional statement and extra info
- deductive: determining whether a conclusion is valid using rules of logic
- inductive: conclusions you draw are based on probability
Conditional Reasoning:
What is a conditional statement?
- “if then” statement that tells us something about the world
- antecedent = “if”
- consequent = “then”
- only tells us what will happen if antecedent occurs, don’t know what happens if antecedent doesn’t occur
Conditional Reasoning:
What is modus ponens, denial of antecedent, affirmation of consequent, modus tollens?
- modus ponens: told “if” is true, conclude that “then” is true (ex. told he did clean up his toys (“if”), conclude that he got a cookie)
- denial of antecedent: told “if” is false, conclude “then” is false; invalid conclusion
- affirmation of the consequent: told “then” is true, conclude if is true, but really an invalid conclusion
- modus tollens: told “then” is false, conclude “if” is false
Conditional Reasoning:
What is the traditional Wason Selection Task? What cards are people supposed to turn over,? What cards do they actually turn over and why?
- 4 cards, one side number, one side letter
- “if card has D on one side, then it has a 3 on the other side”
- should pick D and 7
- mistake: chose 3 (affirmation of consequent) or D (modus ponens)
- also task with squiggle cards
Conditional Reasoning:
What is the modified Wason Selection Task? Describe the 3 examples from class
- modified tasks tap into existing schemas so easier to reason with (relevance to real world experiences)
- ex. “if a person is drinking beer, then they are over 21”
- ex. “if an envelope is sealed, then it has a 20 cent stamp”
- ex. “if entering the country, then must have cholera vaccine”