- Define and explain Behavioural Economics in Policy in your own words
- Use key terms such as bounded rationality accurately
- Apply what you have learned to new examples and questions
- Avoid the common mistakes learners make with this topic
This lesson focuses on Behavioural Economics in Policy: see how governments apply behavioural insights.
See how governments apply behavioural insights.
Key ideas
From homo economicus to real humans
Neoclassical theory models people as rational utility-maximisers with stable preferences. Behavioural economists show decisions are shaped by framing, emotions and social norms: the same product described as '90% fat-free' versus '10% fat' gets very different responses.
Heuristics and biases
Mental shortcuts save effort but cause systematic errors. Anchoring makes the first number we see disproportionately influential; availability bias makes dramatic events feel more likely than they are; present bias makes us overvalue immediate rewards and under-save for retirement.
Key term — bounded rationality: Herbert Simon's idea that rationality is limited by information, time and mental capacity, so people 'satisfice' (settle for good enough) rather than optimise.
Country A uses opt-in organ donation (15% registered); Country B uses opt-out (90% registered). Explain the difference using behavioural economics.
Identify the mechanism: the default option exploits status-quo bias and inertia. Most people stick with the pre-selected option rather than acting to change it. Opt-out still preserves choice — anyone can leave the register — so it is a nudge, not a mandate. The huge gap shows defaults shape behaviour more than preferences alone would predict.
Answer: The default acts as an anchor; inertia keeps most people with it, so opt-out registers far more donors while remaining voluntary — a classic successful nudge.
- Calling every error 'irrational' Behavioural biases are systematic and predictable — that is precisely why they can be modelled and nudged, unlike random errors.
- Assuming lab findings always transfer Behavioural effects are context-dependent; a nudge that works in one culture or setting may fail in another, so field testing matters.
Practice
The idea that people's rationality is limited by information, time and mental capacity, so they satisfice rather than optimise.
Losses hurt roughly twice as much as equivalent gains please, so people avoid risks involving losses.
Framing — the same information presented positively changes choices.
Inertia/status-quo bias: most workers stick with the default of being enrolled rather than opting out.
Quick check
Which of these best defines "bounded rationality"?
What is present bias, and how does it affect saving?
Give one criticism of nudge theory.
- Behavioural Economics in Policy: see how governments apply behavioural insights.
- From homo economicus to real humans: Neoclassical theory models people as rational utility-maximisers with stable preferences.
- loss aversion: The finding from Kahneman and Tversky's prospect theory that losses hurt roughly twice as much as equivalent gains please, making people avoid risks involving losses.
- Watch out for: calling every error 'irrational'