judgement, decision making, reasoning

• Judgement involves deciding on the likelihood of various events

  using whatever information is available. What matters is accuracy.
• Support theory

  • A possible future event seems more likely when it is supported by

  extra information. This is because people fail to remember all the

  relevant information when it is not explicitly mentioned.

  • The observation that we tend to overestimate the likelihood of

  information that can easily be retrieved from memory and underestimate

  the likelihood of information that is hard to retrieve is

  called the availability heuristic.
• Base-rate information

  • People often make little or no use of base-rate information when

  making judgements. This is particularly true when they are getting

  information they have no personal experience with and when

  likelihoods are expressed as probabilities.

  • The observation that we pay too much attention to individuating

  information at the expense of base-rate information is one example

  of the use of the representativeness heuristic, the tendency we

  have to decide that an object belongs to a given category simply

  because it appears typical or representative of that category.
• • Ignoring base-rate information can be overcome by deliberate

  thinking, which is more likely when we question a judgement

  (motivated reasoning) or when the problem formulation emphasises

  the importance of differences in base rate. Judgement also

  tends to be better when the problems are formulated in frequencies

  rather than probabilities or when visual aids are used.
• Why do we keep using heuristics?

  • Laboratory studies have shown situations in which people are

  easily misguided by their heuristics. In daily life, however, heuristics

  are helpful most of the time.
• • Humans seem to have a toolbox of fast and frugal heuristics that help

  them survive and cope with demands. Three of these heuristics are

  the recognition heuristic (what you recognise is more important than

  what you do not recognise), the take-the-best heuristic (go for the option that seems the best, ignore the other options), and the takethe-

  easiest heuristic (go for the option that is easier to understand).

  This, however, does not explain why humans ever developed

  deliberate judgement.
• Dual-process model

  • According to the dual-process model, probability judgements

  depend on processing within two systems. One system is intuitive

  and fast, whereas the other is analytical and slow. We often rely

  solely on the intuitive system.

  • The dual-process model has been examined with judgement problems

  for which the System 1 answer is in conflict with the System 2

  answer. This research indicated that people seem to be sensitive to

  the conflict, even when it is not expressed in their final decisions.

  New versions of the model have been proposed to account for this

  finding.
• Decision making involves selecting from among several possibilities.

  The quality is judged on the basis of the consequences.
• Omission bias

  • Omission bias involves a preference for risking harm from inaction

  rather than action. It is common and has been found in medical

  experts and gamblers. It is due to anticipated responsibility and

  regret. Some individuals use the heuristic, “Don’t just sit there. Do

  something,” and show the opposite to omission bias.
• Utility theory

  • Make choice based on benefits and cost associated w each choice
  • Prev assumed that ppl make decisions rationally, based on abstract, objective, economic principles
  • Rational decision-making = select choice that MAXIMISES EXPECTED UTILITY (value)
  • Gain as much value, avoid lesser value/chance
• According to prospect theory, most people show loss aversion – they

  are much more sensitive to potential losses than to potential gains.

  The framing effect (in which decisions are influenced by irrelevant

  aspects of the situation) and the sunk-cost effect (in which good

  money is thrown after bad) are consistent with the theory.
• Emotional factors

  • Our sensitivity to potential losses occurs in part because our

  emotions (especially fear) make us cautious and risk averse.

  People with damage to brain regions involved in emotional processing

  make more rational decisions. However, they do not make

  better decisions in general than healthy people. As a matter of fact,

  the reverse is true, indicating that emotions are an essential aspect

  in decision making. Emotions represent the wisdom of the ages and

  allow us in general to choose what is good for us and avoid what is

  bad for us, as argued by the somatic marker hypothesis.
• Study context

  • Many decision-making studies are based on verbal answers to

  hypothetical problems. These decisions may differ from the actions

  people take when faced with the same dilemma in real life, as

  shown in a study with mice.
• Social context

  • In the real world, our decision making is influenced by the social

  context and by our need to justify our decisions to other people.

  Decision making sometimes becomes more biased when there is

  increased accountability for decisions.
• Reasoning involves drawing inferences from the knowledge we

  possess. Deductive reasoning involves drawing conclusions that

  are definitely valid (or invalid) provided that other statements

  (premises) are assumed to be true. Inductive reasoning involves

  drawing general conclusions from a sequence of observations. It

  does not guarantee valid conclusions, but generates hypotheses

  that can be tested. Both forms of reasoning are used in scientific

  research and daily life to reach conclusions.
• Syllogistic reasoning

  • A syllogism consists of two premises or statements followed by a

  conclusion. Syllogistic reasoning is part of deductive reasoning.

  Many people make errors in syllogistic reasoning because of belief

  bias. This bias involves focusing on the believability of conclusions

  rather than their logical validity.
• Conditional reasoning

  • Conditional reasoning is a second form of deductive reasoning.

  Many errors are made in conditional reasoning because most

  people have a limited ability to think logically and because they are influenced by irrelevant contextual information. Individuals

  high in working memory capacity perform better than those of

  low capacity.
• • Valid: Modus ponens
  • P1: A, B
  • P2: A
  • C: B (If A true, B is true)
  • Valid: Modus tollens
  • P1: A, B
  • P2: ㄱB
  • C: ㄱA (if B false, A is false)
  • Invalid: affirming the consequent, 
  • A, B
  • B
  • Therefore A (If B is true, A is true)
  • Invalid: denying the antecedent
  • A, B
  • ㄱA
  • Therefore ㄱB (If A is false, B)
• Wason card selection task

  • Performance is generally very poor on the Wason card selection

  task because participants rely on simple strategies, such as the

  matching bias, rather than logical reasoning. Far more correct

  answers are produced when deontic rules are used because such

  rules increase participants’ attention to the possibility that the rule is

  false. Performance is also better when participants are familiar with

  the contents of the problem and are motivated to disprove the rule.
• >>> modified task (Sperber & Girotto, 2002)

  • Use more concrete, familiar items → find task more manageable
  • Julio buys things from the Internet but is concerned he will be cheated. For each order, he fills out a card. On one side of the card, he indicates whether he has paid for the item ordered, while on the other side he indicates whether he has received the item.
• Theories of reasoning

  • According to mental model theory, we construct mental models

  when reasoning. These models represent what is true and ignore

  what is false (principle of truth), even when what is false is relevant

  to solving the problem. Often only a single mental model is formed

  even when there are other possible mental models (principle of

  parsimony).

  • According to dual-process theory, reasoners use simple heuristic

  processes to draw inferences. Time-consuming analytic processes

  are sometimes used to revise or replace the heuristic inferences.
• Informal reasoning

  • Informal reasoning is about the probability of inferences, not about

  their truth. The content of an argument and contextual factors are

  important (unlike in deductive reasoning).

  • In informal reasoning, people are motivated to persuade others of

  their beliefs and views. Such motivation can produce errors (e.g.,

  belief bias, myside bias). However, it can also lead people to reason

  better in some situations.
• • According to the Bayesian model of informal reasoning, the perceived

  strength of a conclusion depends on two factors: the degree

  of prior belief and the strength of the evidence. Hahn and Oaksford

  (2007) further noted that positive arguments are stronger than

  negative ones.
• • The performance of many people on reasoning problems indicates

  that their reasoning is often inadequate. However, the artificiality of

  many of the problems used means that human performance on

  many reasoning problems may underestimate our ability to think

  rationally. People spend much of their time trying to argue persuasively

  rather than to seek out the truth, and this motive can lead to

  errors in tasks on judgement and deductive reasoning.
• At the same time, it cannot be denied that human thinking is limited

  and that this has negative consequences in life. We are rarely aware

  of these consequences because we fail to see the flaws in our

  thinking (the Dunning–Kruger effect). Research in how these flaws

  can be mediated by better information provision is ongoing.
• When describing human rationality, it is better not to use a normative

  framework but a pragmatic framework. Within the pragmatic framework,

  Simon speaks of bounded rationality, which was extended in

  the resource-rational analysis.
• Intelligence and rationality

  • Highly intelligent individuals perform better than those of less

  intelligence on judgement and reasoning tasks. However, the effect

  is often small.

  • According to the tripartite model, intelligent individuals may fail to

  perform well because they lack an algorithmic mind that is good

  enough to override incorrect heuristic responses, or because the

  algorithmic mind is not triggered by the reflective mind. Other

  research has indicated that the three parts of the tripartite model

  are unlikely to be independent of each other.