# Anchoring bias

> IB Psychology · IB Psychology 2027 First Assessment
> Source: https://www.owlsprep.com/study/ib-psychology-cog-anchoring-bias/

The role of anchoring bias in decision-making.

## Learning objectives

- The role of anchoring bias in decision-making.

## How often is this tested?

Based on OwlsPrep's analysis of official CIE IB_PSYCH P1 past papers (2019–2025): **Anchoring bias** appears **3 times** in the last 7 years — **1.3%** of all P1 questions (3 of 228).

Most-tested forms: SAQ: Describe (9 marks) (2), SAQ: Explain (9 marks) (1).

*Small sample — indicative only.*

## Core concept

Anchoring bias is the tendency to rely too heavily on the first piece of information offered (the 'anchor') when making a judgement, adjusting insufficiently away from it. It is a feature of fast, intuitive (System 1) thinking: even an arbitrary or clearly irrelevant number pulls a later estimate towards itself. It matters because it shows human decisions are systematically, predictably biased rather than fully rational.

## Key studies

IB Psychology answers must be supported by named studies. Learn these to cite as evidence:

**Strack & Mussweiler (1997)** — Estimates of Gandhi's age at death were pulled toward an initial anchor, even an absurd one (9 vs 140). — *Demonstrates anchoring with a clearly irrelevant anchor — the effect is not just sensible use of information.*

**Englich, Mussweiler & Strack (2006)** — Experienced judges' sentencing decisions were shifted by a randomly rolled number. — *Shows anchoring affects even trained experts on consequential, real decisions.*

## Evaluation (AO3)

**Strength — robust and consequential** — Replicates across trivial and expert, high-stakes contexts, so it is not a lab curiosity.

**Limitation — mechanism debated** — Whether anchoring works by selective memory access or by insufficient adjustment is still argued, and lab anchors can be more blatant than real-life ones.

## Scope

> **note**
>
> Anchoring is one bias illustrating flawed decision-making; the model that explains it is COG_6. Biases in memory (schema distortion) are a different sub-area (COG_8).

## Common pitfalls

- **Wrong:** Describing anchoring on its own, without linking it to a model of thinking and decision-making.
  - Why it fails: A frequently penalised misconception in IB Psychology exams.
  - Correct: In a 'thinking and decision-making' question, tie the bias to the underlying dual-processing model — the bias is the evidence, the model is the answer.

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From [OwlsPrep](https://www.owlsprep.com) — free study guides for A-Level, IB, AP and IGCSE, written against the official syllabus. Canonical page: https://www.owlsprep.com/study/ib-psychology-cog-anchoring-bias/