What is a Problem? Types of Problems. EXP Dr. Stanny Spring Problem Solving, Reasoning, & Decision Making

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1 Problem Solving, Reasoning, & Decision Making Dr. Director Center for University Teaching, Learning, and Assessment Associate Professor School of Psychological and Behavioral Sciences EXP 4507 Spring 2012 What is a Problem? Discrepancy between the current situation and a desired situation Initial state Goal State Obstacles that make transition between states difficult Problem solving entails: Accurately representing the problem Discovering procedures to eliminate obstacles 2 Well-defined problems Types of Problems Ill-defined problems 3 1

2 Overview Representing problems Strategies for solving problems Expertise and problem solving Impediments to solving problems Creativity 4 Mental Set Bias to adopt the strategy, procedure or interpretation that was used with previous problems Make assumptions that are not justified and that interfere with solution to the problem Functional Fixedness: Focus on typical uses for objects rather than novel uses that will enable solving the problem 5 Luchins Water Jug Problem Jar A 20; Jar B 5; Jar C 130 Need 100 Jar A 12; Jar B 3; Jar C 108 Need 90 Jar A 6; Jar B 1; Jar C 28 Need 20 Jar A 6; Jar B 4; Jar C 44 Need 30 Jar A 10; Jar B 5; Jar C 30 Need

3 Functional Fixedness Failure to recognize multiple uses of objects typically used for other purposes Duncker (1945) candle problem Identify 10 uses for this object: 7 Means-Ends Analysis (Newell & Simon) Problem space Initial state Intermediate state(s) Goal state Operators Actions that alter the problem space Operators may be governed by rules for some problems Means-ends analysis Select operations that reduce the difference between the initial state and the goal state Identify subgoals create useful intermediate states 8 Think-aloud protocol Problem: How to make the problem-solving process public and observable Describe thoughts while solving a problem Features of the problem the solver notices and when the features are noticed Representations used Analogies, models, and other strategies Observe insights Identify differences between novices and experts 9 3

4 Analogies Notice a relation between problem and an analogy Map the relation between features of the problem and features of the analogy Apply the mapping relation to generate a solution (analogy may have a solution that is easier to recognize or access) Surface features Structural features 10 Experts and Novices Experts Larger knowledge base Organization of knowledge: Attend to structural features Spend more time understanding the problem Reason forward from known elements to goal state (solution) Novices Smaller knowledge base Attend to surface features of problems Begin using operators to try to solve the problem quickly Backward reasoning as a strategy (begin with goal state) 11 Creativity in Problem Solving Divergent thinking ill-defined problems Convergent thinking specific problems with correct solutions Remote Associations Test Design fixation

5 Remote Associates Test Assumes creativity requires discovering new relations between concepts. Find a single word that is related to all three of the following words: 13 Reasoning Reasoning by formal logic Formal logic for correct deductions Reframing the Wason four-card problem Analogous problem with drinking age Frame the problem as regulations Frame the problem as permissions 14 Inductive Reasoning Drawing conclusions from evidence Scientific reasoning What factors should you consider when making a decision based on evidence?

6 Strong inductive arguments Observations are likely to be representative Larger samples produce stronger evidence than small samples Observations are related to a predictive model or explanation (theory-driven) 16 Cognitive Illusions: Heuristics & Biases in Decision Making Availability Representativeness Framing Effects Anchoring Illusory Correlation Hindsight Bias Confirmation Bias Overconfidence 17 Fast and Frugal Heuristics Availability works well as a heuristic when ease of retrieval is directly related to frequency of an event Availability produces errors in judgment when additional factors make some items or events easier to retrieve: Events with strong emotion (dread events) Some events receive more media publicity or attention Events that are more distinctive in memory

7 Framing Effects Decisions are influenced by the models we use to think about them 19 Anchoring & Adjustment If all of the human blood in the world were poured into a cube-shaped tank, how wide would the tank be? 20 Evaluating Correlations Suppose a study of 250 neurological patients produces the following observations of the frequencies of dizziness and brain tumors. Which cells of the table are needed in order to determine whether dizziness is associated with brain tumors in this sample of patients? (circle all that apply) Illusory Correlations

8 Performance Hindsight Bias Tendency to perceive decisions and other outcomes as inevitable Knew it all along phenomenon Psychological research is often regarded as common sense and research findings are believed to be predicable once the findings are known 22 Confirmation Bias Tendency to seek information that is consistent with our hypothesis or beliefs Contradictory information is ignored or discounted Note the role of confirmation bias in the selective attention to cells in the dizziness & tumors data 23 Overconfidence Problems in the calibration of confidence Participants express greater confidence in the accuracy of their responses than is justified by their performance Calibration Curve Performance if Confidence Ratings Were Accurate Actual Performance 50% 60% 70% 80% 90% 100% Confidence Rating

9 Why do we use heuristics if they cause errors? Gigerenzer et al. (199) Simple Heuristics that Make Us Smart Heuristics are fast and frugal methods for arriving at decisions that are good enough most of the time Laboratory tasks demonstrate the special circumstances when heuristics backfire and produce an error 25 Improving Decision Making Overconfidence leads to the following problems Do not question quality of decisions made Do not seek better decision-making strategies Provide feedback on performance to improve the calibration of confidence and reduce overconfidence Structure the decision-making environment Force the consideration of alternative options Require an analysis of expected value of outcomes Change culture that prefers decisions made by humans to one that prefers data/statistically-based decisions