Challenges to traditional economic theory

Behavioural economics examines how social, psychological, and emotional factors affect economic decisions. It aims to make economic predictions more realistic by building on traditional theories rather than replacing them entirely.

Key assumptions in traditional economic theory

Traditional economic theory relies on two main assumptions about economic agents, which are individuals or firms making decisions.

These assumptions are:

• Economic agents act as utility maximisers, always seeking to get the most satisfaction or benefit from their choices.
• Economic agents behave rationally, making logical decisions based on available information.

How behavioural economics challenges these assumptions

Behavioural economists argue that these assumptions do not reflect real-world behaviour. People often make decisions influenced by emotions, social pressures, or incomplete information, leading to choices that do not maximise utility. Instead of ignoring traditional theory, behavioural economics refines it to better explain actual decision-making processes.

Rationality and its limitations in decision-making

Rationality assumes that economic agents weigh costs and benefits to maximise net utility or profit. However, real-life constraints often prevent fully rational choices.

Concept of rational behaviour

A rational individual, sometimes called 'homo economicus', compares options by assessing their costs and benefits, then selects the one offering the highest net gain. This requires perfect or symmetric information, where all parties have equal access to complete and accurate data.

Issues with information in real life

• Imperfect information - Economic agents rarely have all the details needed for a fully informed decision, which can result in market failures where resources are not allocated efficiently.
• Asymmetric information - One party in a transaction has more knowledge than the other, such as a seller knowing a product's true production cost and value, while the buyer does not. This imbalance hinders rational decision-making.

As a result, rationality alone cannot reliably predict how consumers or firms will behave.

Restrictions on rational decision-making

Behavioural economists identify several barriers that limit people's ability to make purely rational choices:

• Limited time available to evaluate options.
• Incomplete or inaccurate information.
• Difficulty in processing large amounts of data or calculating costs accurately, known as computation weakness.

These constraints lead to 'bounded rationality', where individuals opt to 'satisfice' by making a good-enough decision rather than spending excessive time seeking the absolute best outcome.

Biases that influence economic choices

Biases are systematic influences that cause individuals to deviate from rational decision-making. Behavioural economists study these to understand why people make certain economic choices.

Common types of biases

• Rules of thumb - Simple heuristics or shortcuts for decision-making, such as selecting a mid-priced item from a range of similar products to avoid overthinking.
• Anchoring - Over-relying on the first piece of information encountered, like allowing an initial price quote to shape perceptions of what is reasonable.
• Availability bias - Judging the likelihood of events based on how easily examples come to mind, for instance, overestimating the chance of a rare weather event after recently experiencing one.
• Social norms - Behaviour shaped by group expectations, such as avoiding a product if it is unpopular within one's social circle.
• Habitual behaviour - Repeating actions out of routine, like always shopping at the same store without considering better alternatives.

These biases show how decisions are often driven by mental shortcuts rather than pure logic.

Bounded self-control and the role of fairness

Traditional theory assumes individuals have complete self-control to maximise utility, but behavioural economics highlights limitations and additional motivations.

Bounded self-control

Individuals often lack full self-discipline, known as bounded self-control. For example, someone might continue an unhealthy habit like excessive spending, even if it reduces their overall well-being or utility.

The influence of fairness on decisions

While traditional theory views actions like charitable giving as self-interested (e.g., gaining personal satisfaction), behavioural economists recognise altruism driven by a sense of fairness.

Individuals and firms may act without expecting direct benefits:

• A person might donate to charity purely because it feels right.
• A firm could pay workers more than the market rate simply to be fair, without guaranteed productivity gains.

This challenges the idea that all economic behaviour stems from self-interest.

Government use of behavioural economics in policy-making

Governments apply behavioural economics to design policies that work in real-world scenarios, moving beyond traditional assumptions. This involves shaping choices to encourage desired behaviours without removing freedom.

Observations from behavioural economics for policy

Insights from bounded rationality, biases, and self-control help governments and firms influence decisions effectively. A key tool is choice architecture, which adapts how options are presented to guide choices.

Methods of choice architecture

• Default options - Setting a standard choice that people are likely to stick with, such as automatically enrolling workers in a savings plan unless they opt out.
• Framing - Presenting information in a way that affects perception, for example, describing a cost as a small daily amount, such as 75 p, rather than a larger weekly total of £5.25 to make it seem more affordable.
• Nudges - Making positive choices easier while keeping alternatives available, like designating specific zones for certain activities to subtly discourage unwanted behaviours.
• Restricted choice - Limiting available options, such as offering only a few local services to choose from.
• Mandated choices - Requiring a decision to be made, for instance, compelling individuals to indicate their preference on a register.

These techniques help policies achieve social and economic goals by aligning with how people actually think and act.