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We prefer to cooperate with compatriots

People are more likely to cooperate with their compatriots than with people from other countries. This tendency can frustrate collaborative projects, such as cross-border cooperation for the provision of public goods. This is the conclusion of Leiden social psychologist Angelo Romano.

Romano published an article about this in leading science journal Nature Communications on 22 July.

Various theories in social psychology suggest that people are more likely to cooperate with in-group members than with out-group ones. This phenomenon is also known as ‘parochialism’. Romano and his colleagues tested the validity of the theory in a large online experiment in 2018, with 18,411 participants from 42 countries. These 42 countries account for around 73% of the world population.

Keep for themselves or give away?

In the experiment, a ‘prisoner’s dilemma game’, the participants had to decide on 12 dilemmas. They took each decision with a unique partner, and did not receive feedback on the decision. For each decision the participants were randomly assigned a partner from the same country, a partner from one of 16 other countries or a partner whose nationality was not revealed. For each dilemma, the participant received 10 monetary units, which they could keep for themselves or give to their partner. It was explained to them that the value of units that they gave to their partner doubled, whereas the value of units that they kept for themselves remained the same. Both partners could give units to their partner or keep them for themselves during a dilemma.

Wijdverbreid parochialisme

The experiments showed that for all 42 nationalities the participants were more likely to cooperate if they knew their partner came from the same country. This led Romano and his colleagues to conclude that national parochialism is a ubiquitous phenomenon, and that it hardly varies across nations. There was also little difference between the situations where the results of the cooperation were public or private. This tendency can have negative effects on cross-border projects that are in the public interest. The researchers mention fighting the Covid pandemic or protecting the environment as examples of cross-border projects.

Reducing the gap

‘A potential lead to reduce the gap is beliefs (expectations)’, says Romano. ‘Part of the less cooperation among people of different nationalities was explained by the fact that people had a belief that people of other nationalities would cooperate less with them. Hence, a potential way to mitigate national parochialism in cooperation could be interventions that target these low expectations about the cooperation of people of different nationalities. Increasing expectations about outgroup’s cooperation could help mitigate discrimination in cooperation among people of different nationality.’

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