- Created by: embarry27
- Created on: 29-12-19 09:34
- Heuristics are cognitive shortcuts that ease the cognitive load of making a decision
How we *should* vs how we actually evaluate inform
- should make a decision that is the most likely to deliver the benefits that we desire.
- BUT - this would be too difficult as it is very time consuming and we can't be sure of the outcome
- most of the time we are 'satisficers' - making adequate inferences and decisions rather than -
- 'optimisers' - drawing the best possible inferences and hence reaching the best possible decisions
System 1 and 2
- System 1 is automatic, intuitive, unconscious, effortless
- System 2 requires attention and effort - slow, controlled, deliberate, statistical
- System 2 engages when circumstances require.
- As people gain knowledge or expertise, the domains of the two systems change.
Applying the 2 systems approach to cognitive heuri
- sample size matters but we often fail to take account of it
- statistics often produce observations that look like they have causal explanations but are instead due to chance....system 1 is the mode of thinking that makes these incorrect causal connections and jumps to (often wrong) conclusions
Some heuristics that highight system 1:
- representativeness heuristic (a mental shortcut whereby instances are assigned to categories on the basis of how similar they are to the category in general)
- availability heuristic (people make judgements about the likelihood of an event based on how easily an example, instance, or case comes to mind.
- adjustment and anchoring (anchoing is when someone starts with a point and makes adjustments to it to reach their estimate)
Why do we make these mistakes?
- base rate information
- predictive value (how credible is the source?)
- small sample size less reliable
Overcoming tendency to overlook base rates
- instruct people to 'think like a statistician'
- instructing people to 'think like a clinician' has the opposite effect
- frowning increases vigilence which leads to enhanced activation of System 2 and consequently increased use of base rate info
- cognitive shortcut that relies on immediate examples that come to a given person's mind when evaluating specific concept or decision
Biased estimates can occur for two reasons
- it's not only about frequency, what about familiarity and salience?
- our own experiences with things happening frequently might be idiosyncratic
So why do we do it?
- The feeling of difficulty/ease of retrieval (system 1) can matter as much as the absolute numbers (content) (system 2)
- one of the most robust and reliable resulsts in experimental psychology
- makes us place weight upon anchors and as a result means we may not always adjust sufficiently far from these anchors to provide accurate judgements
So why do we do it?
- Tversky: deliberate (if insufficent) attempt to adjust from an irrelevant value that provides an anchor: system 2
- Kahneman: anchoring that occurs by priming: system 1
Argued that both of these are right but it depends...
- (system 2:) Found that adjustment is effortful (system 2) and under cognitive load, people adjust less.
- (system 1:) shown by Mussweiler et al (2000) where anchor primed associated concepts in memroy - 20 degrees as an anchor made it easier to recognise words like sun, and 5 degrees made it easier to recognise words like ski