BEHAVIOURAL SCIENCE IS WEIRD

Even as you read this, many of the top psychological journals are publishing research on a sample of people that are…WEIRD.

WEIRD stands for Western, Educated, Industrialised, Rich, and Democratic, describes a small subset of people that makes up only 12% of the global population.

However, this subset is predominantly comprised of psychology undergrad students, accounting for 96% of all samples used in studies published by top psychological journals.

The problem is that scientists regularly draw conclusions about how entire societies behave based on a small sample of WEIRD people. Designing behavioural interventions based on samples that are do not represent the target population of the intervention can potentially do more harm than good.

Let’s look at two examples:

EXAMPLE 1: Ultimatum

Replications of the renowned economic experiment, the Ultimatum game, found that people in small scale societies think very differently about cooperation and fairness than do their WEIRD counterparts. The Ultimatum game tests how much money one person is willing to offer to another to reach a deal in which both are better off. In the game one person is giving the money, and the other chooses whether to accept or reject the offer. Interestingly, people from WEIRD samples offered between 40% — 50% of the money given in the experiment, and offers below 30% were often rejected. However, when this same experiment was conducted in small societies, proposers made low offers and responders accepted offers well below 30%.

EXAMPLE 2: Lines

In another example, researchers presented participants from 17 cultures with the well-known Müller-Lyer Illusion.

The results found that cultural differences changed how people viewed the illusion. WEIRD participants perceived line A as at least 20% longer than line B. However, some non-WEIRD participants were completely unaffected by certain illusions.

Conclusion

Therefore, as behavioural economists, it is important to understand that context matters, including the environment, culture, and accessibility to resources of a society. These variations in context can have a significant impact on the outcomes of individuals’ behaviour.