Cognitive biases in decision-making
IB PsychologyΒ· Learning and cognitionΒ· 14 min read
1. Core concept
Cognitive biases are systematic, predictable errors in judgement that shape how people actually decide. Anchoring makes a first number pull a later estimate towards itself, even when that number is irrelevant; confirmation bias makes people seek information that supports what they already believe rather than what could disprove it. In the learning-and-cognition context the payoff is applied: because these biases are regular rather than random, they explain why even experts and careful reasoners make the same mistakes, and where interventions might help.
2. Key studies
IB Psychology answers must be supported by named studies. Learn these to cite as evidence:
Englich, Mussweiler, and Strack (2006)
Experienced judges' sentencing decisions were shifted by a randomly generated (dice-rolled) number, an anchor they should have disregarded. β Anchors the ANCHORING subclass in a real, high-stakes decision β showing a bias operating in professional judgement, not just a lab curiosity.
Wason (1968)
In the four-card selection task, people typically looked for confirming evidence rather than the card that could falsify the rule. β Anchors the CONFIRMATION subclass β biased evidence-seeking as a feature of everyday reasoning.
3. Evaluation (AO3)
Strength β robust and consequential β The same biases replicate across trivial estimates and expert, real-world decisions, so they describe how judgement genuinely works rather than an artefact of one task.
Limitation β labelling β explaining β Naming a bias is not an account of decision-making; without the underlying dual-processing model (why fast, intuitive thinking produces it), a 'bias' is only a description, and lab anchors are often more blatant than real-life ones.
4. Scope
5. Common Pitfalls
Wrong move:
Describing a bias on its own (e.g. 'anchoring is relying on the first number') and treating that as an answer about decision-making.
Why:
A frequently penalised misconception in IB Psychology exams.
Correct move:
Tie the bias to the decision it distorts and to the fast, intuitive (System-1) processing that produces it β the bias is the evidence, the model is the explanation.
Going deeper
- Dual processing theorythe model that EXPLAINS why these biases occur (fast System-1 thinking) is dual-processing theory β COG_6; this card applies the biases, it does not re-derive the model.
- Anchoring biasthe mechanics of anchoring as a standalone concept are COG_1; here it is used as one example of a decision bias.
- Confirmation biasconfirmation bias's concept home is COG_5.