chapter 12 Flashcards
deductive reasoning
you begin with some speciic premises that are true, and you need to judge whether those premises allow you to draw a particular conclusion, based on the principles of logic
conditional reasoning task
describes the relationship between conditions. Here’s a typical conditional reasoning task:
If a child is allergic to peanuts, then eating peanuts produces a breathing problem.
A child has a breathing problem.
Therefore, this child has eaten peanuts.
syllogism
consists of two statements that we must assume to be true, plus a conclusion.
propositional calculus
a system for categorizing the four kinds of reasoning used in analyzing propositions or statements.
antecedent
the irst proposition or statement; the antecedent is contained in the “if…” part of the sentence.
consequent
the proposition that comes second; it is the consequence. The consequent is contained in the “then…” part of the sentence.
Afirming the antecedent
Afirming the antecedent means that you say that the “if…” part of the sentence is true. This kind of reasoning leads to a valid, or correct, conclusion.
afirming the consequent
means that you say that the “then…” part of the sentence is true. This kind of reasoning leads to an invalid conclusion.
denying the antecedent
means that you say that the“if…”part of the sentence is false. Denying the antecedent also leads to an invalid conclusion.
Denying the consequent
means that you say that the “then…” part of the sentence is false. This kind of reasoning leads to a correct conclusion.
heuristic
a general strategy that usually works well.
dual-process theory
which distinguishes between two types of cognitive processing, type 1 and 2.
Type 1 processing
Type 1 processing is fast and automatic; it requires little conscious attention.
Type 2 processing
is relatively slow and controlled. It requires focused attention,and it is typically more accurate.
belief-bias effect
occurs in reasoning when people make judgments based on prior beliefs and general knowledge, rather than on the rules of logic.
confirmation bias
they would rather try to conirm or support a hypothesis than try to disprove it. want to confirm antecedent, hesitant to deny consequent.
decision making
you must assess available information and choose among two or more alternatives.
Daniel Kahneman and Amos Tversky
proposed that a small number of heuristics guide human decision making. The same strategies that normally guide us toward the correct decision may sometimes lead us astray
representative
if it is similar in important characteristics to the population from which it was selected.
representativeness heuristic
we judge that a sample is likely if it is similar to the population from which this sample was selected. we believe random looking outcomes are more likely than orderly
small-sample fallacy
they assume that a small sam- ple will be representative of the population from which it is selected
base rate
how often the item occurs in the population.
base-rate fallacy
paying too little attention to important information about base rate.
conjunction rule
the probability of the conjunction of two events cannot be larger than the probability of either of its constituent events.
conjunction fallacy
they judge the probability of the conjunction of two events to be greater than the probability of either constituent event.
how we use the representativeness heuristic.
- We use the representativeness heuristic when we make decisions based on whether a sample looks similar in important characteristics to the population from which it is selected.
- The representativeness heuristic is so appealing that we tend to ignore other important characteristics that we should consider, such as sample size and base rate.
- We also fail to realize that the probability of two events occurring together (e.g., bank teller and feminist) needs to be smaller than the probability of just one of those events (e.g., bank teller).
availability heuristic
You use the availability heuristic when you estimate frequency or probability in terms
of how easy it is to think of relevant examples of something
remembering heuristics
- If the problem is based on a judgment about similarity, you are dealing with the representativeness heuristic.
- If the problem requires you to remember examples, you are dealing with the availability heuristic.
recency and availability
we recall recent items, people judge recent items to be more likely than they really are.
recognition heuristic
typi- cally operates when you must compare the relative frequency of two categories; if you recognize one category, but not the other, you conclude that the recognized category has the higher frequency.
illusory correlation
occurs when people believe that two variables are statistically related, even though there is no actual evidence for this relationship.
social cognition approach
stereotypes can be traced to our normal cognitive processes. In the case of illusory correlations, an important cognitive factor is the availability heuristic.
framing effect
demonstrates that the outcome of your decision can be inlu- enced by two factors: (1) The background context of the choice and (2) the way in which a question is worded—or framed
Overconidence
means that your conidence judgments are higher than they should be, based on your actual performance on the task.
crystal-ball technique
asks decision makers to imagine that a completely accurate crystal ball has determined that their favored hypothesis is actually incorrect; the decision makers must, therefore, search for alternative explanations for the outcome
The beliefs that gay people tend to have psychological problems, that blondes tend
not to be very intelligent, and that paranoid people draw faces with exaggerated
eyes are all mainly examples of:
illusory correlation.
A person estimates the population of Tokyo, based on what she knows about the
population of New York City, taking into account that she thinks Tokyo is a slightly
larger city. Which heuristic is she using?
anchoring and adjustment.
The planning fallacy is the common tendency to:
a) underestimate the amount of time or money needed to complete a project.
People are overconfident in what they could have predicted had they made a judgment
before knowing an actual outcome. That is, they overestimate the accuracy
with which they would have predicted an event had they been asked to do so. This
is called the:
hindsight bias.
One important factor that sometimes leads to distortions in frequency estimates based on the availability heuristic is:
The amount of media coverage of a topic.
Suppose you are going to buy a new car and the first price that is mentioned is $21,499. According to the anchoring heuristic, the most likely final price is
$21,273
Research on the framing effect reveals that people:
Are influenced by background context, as well as the way in which a question is worded.
People use anchoring and adjustment processes when they estimate confidence intervals. This may lead them to:
Give confidence intervals that are overly narrow.
A person estimates the population of Tokyo, based on what she knows about the population of New York City, taking into account that she thinks Tokyo is a slightly larger city. Which heuristic is she using?
Anchoring and adjustment.
In one study, people were asked to estimate the length of the Mississippi River after they answered a question: “Is it longer than 500 miles?” or “Is it longer than 5,000 miles?” Estimates were much smaller in the former case than in the latter case, suggesting that the estimate was influenced by:
An anchor.
The beliefs that gay people tend to have psychological problems, that blondes tend not to be very intelligent, and that paranoid people draw faces with exaggerated eyes are all mainly examples of:
Illusory correlation.
The availability heuristic can be biased by
Both recency and familiarity
With the representativeness heuristic, we
Judge a sample to be more likely if it is similar to the population from which it was selected.
Our problem-solving ability is biased, as described by
Both the belief-bias and the confirmation- bias effects.
Consider the following reasoning: “If Frank’s car started, then he went to town. Frank’s car did not start. Therefore, Frank did not go to town.” Many people will accept the conclusion as being logical because they committed an error called:
Denying the antecedent.
In the dual-process theory of problem solving,
Type 1 processing requires little conscious attention.
A major way in which tasks requiring decision making differ from tasks requiring deductive reasoning is that the decision-making area:
Is much more ambiguous.
Cannot be handled by using heuristics.
Is much less common in real life.
