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Chapter 6 – Judgement and decision making

This chapter is concerned with two related processes – judgement and decision making. We start off by looking at how we make judgements, specifically considering the role that probability judgements, for example availability and representativeness heuristics, play in people’s probability judgements. We provide some judgement examples for you to try and take a look at how heuristics impact the real-world judgement and decision making example of medical diagnosis. We also explore Bayseian inference and consider whether natural-frequency information (in contrast to laboratory based studies of judgement) facilitates judgement-making. In the last part of the chapter, we explore dual processes of judgement, the idea that we can use System 1 thinking to make fast intuitive judgements and System 2 to make slower more considered judgements.

  • Chapter 6 – Flashcards

    judgements

    The internal capacity for thoughts, opinions and evaluations of events and people.

    decision making

    The behaviour of choosing between alternative options.

    normativism

    The idea that human thinking reflects a normative system against which it should be measured and judged.

    descriptive approach

    An approach concerned with how we in fact reason and think rather than how we should do so.

    risk

    A decision making situation where the decision involves the possibility of an adverse consequence or outcome.

    framing

    A cognitive bias where people decide on options based on whether the options are presented in a positive or negative way.

    heuristics

    Simple rules that can be used instead of more complex decision making processes.

    availability heuristic

    A mental shortcut where people make judgements about the likelihood of an event based on how easily previous instances come to mind.

    subadditivity effect

    A tendency to judge the probability of the whole as being less than the probability of its constituent parts.

    representativeness heuristic

    A mental shortcut that describes judgements that tend to be based on how similar an event is to a prototypical example of that category.

    conjunction fallacy

    A faulty line of reasoning that infers that the combination of two or more attributes is more probable than either attribute on its own.

    bayesian inference

    An approach to applying probability to statistical problems that involves updating beliefs about events in light of new data or existing evidence about those events.

    base-rate information

    The underlying general prevalence or relative probability of a type of event occurring.

    base-rate neglect

    The tendency to underweight or ignore base-rate information in favour of other types of information when making judgements.

    anchoring and adjustment heuristic

    A mental shortcut that describes judgements that are heavily influenced by the initially presented set of information.

    natural sampling

    A process by which experiences about events is acquired naturally and forms the basis of probability judgements.

    fast-and-frugal heuristics

    A type of heuristic that is simple to execute because they limit information search and do not involve much computation.

    recognition heuristic

    A mental shortcut that describes that when making a judgement about two items, the individual will judge the most easily recognised item as having the higher value.

    System 1 thinking

    Used to describe an intuitive reflex system which triggers an automated mode of thinking.

    System 2 thinking

    A form of analytical, deliberate and rational thinking process, characterised by logical thought and a mental search for additional information.

  • Chapter 6 – Weblinks

Chapter 6 – Quiz