Reasoning and Intelligence Chapter 10 How People Reason Analogy and Induction Analogy similarity in behavior function or relationship between entities or situation that are in other respects different from each other Inductive Reasoning Induction inference of a new principle on the basis of observations or facts reasoning from the specific to the general Analogy in scientific reasoning E g Memory and computers Analogy in judicial and political reasoning Analogy problems Miller Analogy Test Raven s Progressive Matrices How People Reason Analogy and Induction Miller Analogy Example Used to generate hypotheses Example Observation 1 Observation 2 Inference 1 Observation 3 Inference 2 Observation 4 Inference 3 2 8 20 44 Inductive Reasoning Biases Availability heuristic example 4 10 22 46 6 12 24 48 Name words starting with k Name words with the letter k in the third position Answer k is 2 3 times more likely to be in the third position Because it is easier to recall words starting with k people overestimate the number of words starting with k Inductive Reasoning Biases Confirmation bias the tendency confirm rather than disconfirm one s current hypothesis Example reading newspaper columnists who agree with our point of view and avoiding those who don t Inductive Reasoning Biases Representativeness Heuristic judging the probability of an event based on how it matches a prototype But can also lead to errors and is the basis of prejudice Inductive Reasoning Biases Representativeness heuristic example 1 Chris is 6 7 300 pounds has 12 tattoos was a champion pro wrestler owns nine pit bulls and has been arrested for beating a man with a chain Is Chris more likely to be a man or a woman A motorcycle gang member or a priest How did you make your decision Inductive Reasoning Biases Representativeness heuristic example 2 Tracy is meek and tidy has a passion for detail is helpful to people but has little real interest in people or real world issues Is Tracy more likely to be a librarian or a salesperson How did you come to your answer Deduction Reasoning Deduction attempt to derive logically the consequences that must be true if certain premises are true reasoning from the general to the specific A transitive relation is such that if it applies between successive members of a sequence it must also apply between any two members taken in order For instance if A is larger than B and B is larger than C then A is larger than C Syllogism a form of argument where a conclusion is deduced from two An argument is valid if and only if it is impossible that its premises be or more premises or proposition true and its conclusion is false An argument is invalid if and only if it is possible that is premises be true and its conclusion is false A sound argument is a valid argument with true premises Deduction Reasoning Are any of the arguments below valid or sound Why or why not A Invalid Affirming the consequent B Invalid Denying the antecedent C Is not sound Deduction Reasoning Knowledge bias in deductive reasoning Consider the following two syllogisms Is A correct Is B correct Mental model theory of deduction To solve a syllogism you might visualize the statements Syllogisms that are easy to visualize are more readily solved than more abstract syllogisms If Mary is a chef then she is a violinist A Mary is a chef if and only if she is a violinist B Insight Solving a problem free of mental sets Mental set well established habits of perception or thought Example problems Mutilated checkerboard problem Candle problem Illustrates functional fixedness failure to see an object as having a function other than its usual one Consider this problem A man is at work and wants to go home He cannot go home because there is a man waiting for him there wearing a mask What does the man who wants to go home do for a living Unconscious processes do not require explicit working memory may be more important for insight as opposed to deductive problems Priming during an incubation period Two General Problem solving Strategies 1 Algorithms rules that if followed correctly will eventually solve the problem Includes any rule requiring a list e g recipes computer programs 2 Heuristics Any rule that allows one to reduce the number of operations that are tried in problem solving also know as rules of thumb Do not guarantee a correct solution and can either help or hinder problem solving Relies heavily on schemas in long term memory The availability and representativeness heuristics can lead to irrational thinking Some heuristics are helpful Create subgoals Working backwards Is a doctor s diagnosis an algorithm or heuristic Culture and Reasoning Non western responses to western logic problems Whole vs parts Language and reasoning Linguistic relativity Egocentric frame of reference Absolute frame of reference Number Systems Intelligence Testing Francis Galton Intellectual achievement is innate Nature Manifested in mental quickness and sensory acuity Used reaction time as a measure of intelligence Developed the precursor to the correlation coefficient Student Karl Pearson refined the measure we know today Alfred Binet Intelligence is a collection of various higher order mental abilities only loosely related to one another Intelligence is develops with interaction with the environment Nurture Developed first intelligence test as an attempt to identify children needing remedial academic attention IQ Mental Age Chronological Age X 100 Intelligence Testing David Wechsler s Modification used in the WISC and WAIS Validity of Intelligence Testing Validity a measure is valid if it measures what it intends to measure Predictive validity In this case how well does the IQ score predict achievement outside of school For jobs requiring high mental complexity IQ tests are better predictors of performance than any other measure developed to date including measures testing specific knowledge and skills related to the job What IQ tests predict General Intelligence Spearman s g factor general intelligence underlying ability contributing to performance on all mental tests Raymond B Cattell modified Spearman s theory Crystallized intelligence mental ability derived from experience Fluid intelligence ability to use reasoning skills and find relationships in the environment independent of previous specific practice Other Bases for g possible related to fluid intelligence Mental speed Working memory capacity Mental self government Self regulation and the