Chapter 13 - Judgement, Decisions and Reasoning Flashcards
-judgement:
about appearance etc
-Decisions:
the process of making choices between alternatives, based on judgements that we make
-Reasoning:
the process of drawing conclusions
Inductive Reasoning
- the process of drawing general conclusions based on specific observations and evidence, the conclusions we reach are probably but not definitely true
- reasoning that is based on observation
- reaching conclusions from evidence
inductive reasoning
-Observation
-all the crows I’ve seen in Pittsburg are black. When I visited my brother in Washington, DC, the crows I saw there were back too
Conclusion
-I think it is a pretty good bet that all crows are black
Strength of Argument
- representativeness of observations – how well do the observations about a particular category represent all the members of that category?
- number of observations
- quality of observations
Used to make scientific discoveries
inductive reasoning
hypothesis and general conclusions
Used in everyday life
inductive reasoning
-make a prediction about what will happen based on observation about what has happened in the past
Heuristics
- ”rules of thumb” that are likely to provide the correct answer to a problem, but are not foolproof
- provide us with shortcuts to help us generalize form specific experiences to broader judgements and conclusions
- two more commonly used heuristics include the availability heuristic and the representativeness heuristic
-Availability heuristic:
events more easily remembered are judged as being more probable than those less easily remembered (Tversky and Kahneman, 1973)
- Which is more prevalent, words that begin with letter r, or words in which r is the third letter?
- Most people stated that there are more words that start with r. Actually, there are three times more words that have r in the third position
Illusory Correlations:
correlation appears to exist, but either does not exist or is much weaker than assumed. Wearing a “lucky shirt” for a certain outcome to occur, no real relationship exists
stereotypes:
oversimplified generalizations about a group or class of people that often focuses on the negative -selective attention to the stereotypical behaviours makes these behaviours more available, based on the availability heuristic (Chapman and Chapman, 1969)
-Representativeness heuristic:
the probability that A is a member of class B can be determined by how well the properties of A resembles properties normally associated with class B
- based on how much an event resembles other events
- the probability that A come from B can be determined by how well A resembles properties of B
- use base rate information if it is all that is available
- base rate: the relative proportion of different classes in the population
- use descriptive information if available and disregard base rate information
- we randomly pick on male from the population of the US. The male, Robert, wears glasses, speaks quietly, and reads a lot. Is it more likely that Robert is a librarian for a farmer?
-Use base rate information if it all that available
- In a group of 100 people, there are 30 farmers and 1 librarian. We pick one male, Robert. Is it more likely that Robert is a librarian or a farmer?
- Use descriptive information and disregard base rate information
- in a group of 100 people, there are 30 farmers and 1 librarian, and we pick Robert
- The male, Robert, wears glasses, speaks quietly, and reads a lot. Is it more likely that Robert is a librarian for a farmer?
Conjunction rule:
probability of two events cannot be higher than the probability of the single constituents
- but 81% of participants picked two - bank teller, feminist example
Heuristics cont’d (ignore law of large number)
-law of larger numbers:
the larger the number of individuals randomly drawn from a population, the more representative the resulting group will be of the entire population
- from a group of 10,000 people (5000 males and 5000 females), we choose two groups. First group with 1000 people and the second group with 10 people
- for which group, the percent of males will be closer to 50% - larger
confirmation bias:
tendency to conform rather than falsify hypothesis, people look for information that confirms their hypothesis and ignore information that refutes it
-the myside bias:
tendency for people to generate and evaluate evidence and test their hypothesis in a way that is based towards their own opinions and attitudes
- Lord and coworkers (1979) had those in favor of capital punishment and those against it read the same article - those in favor found the article convincing - those against found the article unconvincing
the backfire effect:
a person’s viewpoint could actually become stronger when faced with corrective facts opposing their viewpoints
Deductive Reasoning
-determining whether a conclusion logically follows from statements (premises)
syllogism:
- basic from of deductive reasoning
- two statements called premises
- third statement called conclusion
-categorical syllogism
- describe relation between two categories, using all, no, or some
- syllogism is valid if conclusion follows logically from its two premises
- validity in this context indicates that the conclusion follows logically from its two premises
- Aristotle’s “perfect” syllogism
- Premise 1: All A are B
- Premise 2: All B are C
- Conclusions: therefore, all A are C
- If two premises of a valid syllogism are true, the syllogism’s conclusion must be true
- do not confuse “validity” with “truth”
- Premise 1: all birds are animals
- premise 2: all animals have 4 legs
- premise 3: all birds have 4 legs- valid but premise 2 and the conclusion are not true
-invalid syllogism but the premises and conclusions could be true
- premise 1: all of the students are tired
- premise 2: some tired people are irritable - premise 3: some of the students are irritable
-so, this syllogism is not valid because both premises are true, but the conclusion is not
-premise 1: all of the cats are tired
Premise 2: some tired animals are dogs Premise 3: some of the cats are dogs
-belief bias:
the tendency to think a syllogism is valid if its conclusion is believable
-good reasoning and truth is not the same thing
How Well Can People Judge Validity?
-Evaluation:
ask people if conclusions follow logically from premises
Production:
ask people indicated what logically follows from premises
-Many errors in evaluation
-Valid but believable
Premise 1: All birds are animals
- Premise 2: All animals have four legs
- Conclusion: All birds have four legs
-Invalid but believable
- Premise 1: All of the students are tired
- Premise 2: Some tired people are irritable
- Conclusion: Some of the students are irritable
Mental Model Approach
- Mental Model (Johnson-Laird, 1999b): a specific situation represented in a person’s mind that can be used to help determine the validity of syllogism in deductive reasoning
- create a model of a situation based on the premises
- generate tentative conclusions about model
- look for exceptions to falsify model
- determine validity of syllogism
Deductive Reasoning
-Conditional syllogisms
the first premise is a “if…then”
- If p, the q. (1sr premise) - p is antecedent, q is consequent - for 2nd premise, there are 4 ways - affirming the antecedent (now p) - denying the consequent (now not q) - affirming the consequent (now q) - denying the antecedent (now not p)
-Condition syllogisms
- ”If p, then q”
- is it q. Affirming the consequent (NOT valid)
- If it’s robin, then it’s a bird
- it’s a bird (sparrow is a bird)
- therefore, it’s a robin (sparrow is a robin)
- Not P, Denying the antecedent (NOT Valid)
- If it is a robin, then it’s a bird
- It’s not a robin (sparrow is not a robin)
- Therefore, it’s not a bird (sparrow is not a bird)
The Wason 4-Card Problem
- effect of using real-world items in a conditional-reasoning problem
- determine minimum number of cards to turn over to test: if there is a vowel on one side, then there is an even number on the other side
Falsification principle:
to test a rule, you must look for situations that falsify the rule
- most participants fail to do this - when problem is stated in concrete everyday terms, correct responses greatly increase - would need to turn over the E and 7 to test the rules
-pragmatic reasoning schema:
thinking about cause and effect in the world as part of experiencing everyday life
permission schema:
if A is satisfied, B can be carried out
- used in concrete versions - people are familiar with rules
Evolutionary Perspective on Cognition
- Evolutionary principles of natural selection
- wason task governed by built-in cognitive program for detecting cheating
- in contrast to permission schema
-Social Exchange Theory
-an important aspect of human behaviour is the ability of two people to cooperate in a way that is beneficial to both of them
-Cosmides and Tooby (1992)
- created unfamiliar situations where cheating could occur
- if a man eats cassava root, then he must have a tattoo on his face
- participants did well
- evidence against permissions schema
Conditional Reasoning
- What is clear so far are
- context is important
- familiarity is not always important
Decision Making
-Expected utility theory
- people are rational
- if they have all the relevant information, they make a decision that results in maximum expected utility
-utility:
outcomes are desirable because they are in the person’s best interest
-maximum monetary payoff
-advantages for utility approach
-specific procedures to determine the “best choice:
-Problems for utility approach
- not necessarily money, people find value in other things
- many decisions do not maximize the probability of the best outcome
Emotions effect decisions
-Expected emotions
- emotions that people predict that they will feel concerning an outcome
- a determinate of risk aversion: the tendency to avoid taking risks
-immediate emotions
- experienced at the time a decision is being made
- people inaccurately predict their own emotions
-incidental emotions:
emotions that are not specifically related to decision-making
- may be related to one’s general disposition or personality, some recent experience, or one’s general environment or surroundings - can affect one’s overall decisions making processes
-focusing illusion:
focus on just one aspect of a situation and ignore other aspects that may be important
- dating and happiness
- how happy are you?
- how many dates did you have last month?
- correlation higher is ask dating first
opt-in procedure
-active step to be organ donor
out-out procedure
-organ donor unless requested not be
-status-quo bias
-the tendency to do nothing when faced with deciding
Risk-Taking Strategies
-Risky decisions
- risk-aversion strategy used when problem is stated in terms of gains
- risk-taking strategy when problem is stated in terms of losses
-framing effect:
decisions are influenced by how a decision is stated
- can highlight one aspect of a situation - Tversky and Kahnemann (1981) - when situations are framed in terms of gains, people tend toward a risk-aversion strategy - when situations are framed in terms of losses, people tend toward a risk-taking strategy
-decision making process includes looking for
for justification so a rationale is presented with decision (Tversky and Shafir, 1992)
- you have taken a tough exam. You passed it (failed it or will know the result in two days). You have an opportunity to buy a very attractive 5-day Christmas vacation package. - buy, not buy, pr pay $5 to retain the rights to buy the vacation the day after tomorrow - ” pass and “fail” are both good reasons for a trip - this is why doctors may carry out medical tests that might not lead to different treatments
-Neuroeconomics
-one finding: decisions are influenced by emotions, and those emotions are associated with activity in specific areas of the brain
-Sanfey and coworkers (2003)
- ultimatum game
- often rejected low offers because they became angry that offers were unfair
- less angry with an “unfair” computer
- more activation of right anterior insula (connected with emotional states), participants more likely to reject more offers
- emotion is important in decisions-making
The Dual Systems Approach to Thinking
-Kahnemann (2011)
- two mental systems
- system 1: fast, automatic, intuitive, unconscious
- system 2: slower, deliberative, conscious, controlled
- much of our day-to-day existence is handled by system 1
- system 2 takes over when we need to be more thoughtful
The Dual Systems Approach to Thinking
-Stanovich and West (2000)
- favor terms Type 1 processing and Type 2 processing
- similar characteristics as Kehneman’s System 1 and system 2 concept
- favored by many researchers because better reflects the interconnected, distributed processing that occurs in the brain
