Cognition Ch.12 (Done)
Syllogism
A form of deductive reasoning consisting of a major premise, a minor premise, and a conclusion. •two conditions that are assumed to be true, plus a conclusion •Frequently contain statements about quantities including all, none, or some 1.All Psych majors are friendly people 2.Some friendly people are concerned about poverty 3.Therefore, all Psych majors are concerned about poverty (Valid?)
Abductive reasoning
Abductive reasoning typically begins with an incomplete set of observations and proceeds to the likeliest possible explanation for the set.
Hindsight bias
The tendency people have to view events retrospectively as more predictable than they really are. Before an event takes place, while you might be able to offer a guess as to the outcome, there is really no way to actually know what's going to happen. --3 cognitive processes assumed to underlie hindsight bias: 1.recollection bias, 2.reconstruction bias, and 3.the tendency to adopt newly acquired knowledge as old.
background knowledge (Belief bias effect)
can often influence how we evaluate problems of logic •If a feather is thrown at a window, the window will break. •A feather is thrown at a window. •Therefore, the window will break. Valid or Invalid The belief-bias effect occurs in reasoning when people make judgments based on prior beliefs and general knowledge, rather than on the rules of logic. ---•An example of top down processing
Conditional reasoning (deductive reasoning task)
the relationship between conditions if ...then" type reasoning
Propositional calculus (Overview of conditional reasoning)
• a system for categorizing the kinds of reasoning used in analyzing propositions or statements •Antecedent - the first proposition or statement •The 'if' part of the sentence •Consequent - the proposition that comes second •The 'then' part of the sentence
Decision making
•In decision making there are no established rules or clear-cut decisions •What to eat for dinner? •What to do after college? •Should additional taxes be collected to improve education? •People who study decision making often focus on our use of heuristics to make decisions
Base rate effect (representative heuristic)
•People also ignore the base rate or how often an item occurs in the population. • •Base-rate fallacy - paying too little attention to important information about base rate • •Example • •Tom is an opera buff who enjoys touring art museums when on vacation. Growing up, he enjoyed playing chess with family members and friends. Which situation is more likely? • 1.Tom plays trumpet for a major symphony orchestra 2.Tom is a farmer
Difficulties with abstract reasoning
•People are more accurate when they solve reasoning problems that use concrete examples rather than abstract, theoretical examples •If an object is red then it is rectangular •This object is not rectangular •Therefore, it is not red (valid or invalid?) •Accuracy increases when you use diagrams to make problems more concrete
Difficulties with negative information
•People have more difficulty with conditional reasoning tasks that contain negative information •People take longer to evaluate problems that contain negative information • •People are also more likely to make errors on these types of problems
•Tversky and Kahneman (1983): Linda Problem (rep heurisitic)
•Probabilistically, this makes no sense •Conjunction rule- probability of two events together cannot be larger than either of the constituent events •Conjunction fallacy - judge the probability of the conjunction of two events to be greater than the probability of either constituent event even those with advanced level of statistics, they still succumb to conjunction fallacy
Representativeness heuristic
•Representativeness heuristic- we view a sample as likely if it is similar to the population from which the sample was selected ----We believe that random looking outcomes are more likely than orderly outcomes •The heuristic is so persuasive that we often ignore information that we should consider
Standard Wason Selection Task (Confirmation bias)
•Standard Wason Selection Task •People show a confirmation bias •Try to confirm a hypothesis rather than disprove it •89% of participants turn over the 'E' card •Affirms the antecedent •The other valid method is to turn over the '7' and deny the consequent •This would be a method of rejecting the hypothesis •Turning over the '6' or 'J' would not be a valid method of testing this cannot affirm consequent and deny antecedent
•Sample size and representativeness (representative heuristic)
•When we make decisions we often fail to pay attention to sample size •A large sample is statistically more likely to reflect the true proportions in a population than a small sample •Small sample fallacy- people assume that small samples will be representative of the population at large •e.g. stereotypes
Availability Heuristic
•when people estimate frequency or probability based on how easy it is think of examples of something •Testing the availability heuristic involves asking people questions and having them provide examples ---Which are deadlier: Sharks or Horses? ---•Heuristic is usually accurate, but is 'contaminated' by recency and familiarity
Deductive reasoning
•you are given specific premises, and then you are asked whether those premises allow you to logically draw a particular conclusion Deductive reasoning is sometimes referred to as top-down logic. Its counterpart, inductive reasoning, is sometimes referred to as bottom-up logic •Where deductive reasoning proceeds from general premises to a specific conclusion, inductive reasoning proceeds from specific premises to a general conclusion.