Cooperation and coordination in heterogeneous populations

Abstract

One landmark application of evolutionary game theory is the study of social dilemmas. This literature explores why people cooperate even when there are strong incentives to defect. Much of this literature, however, assumes that interactions are symmetric. Individuals are assumed to have the same strategic options and the same potential pay-offs. Yet many interesting questions arise once individuals are allowed to differ. Here, we study asymmetry in simple coordination games. In our set-up, human participants need to decide how much of their endowment to contribute to a public good. If a group’s collective contribution reaches a pre-defined threshold, all group members receive a reward. To account for possible asymmetries, individuals either differ in their endowments or their productivities. According to a theoretical equilibrium analysis, such games tend to have many possible solutions. In equilibrium, group members may contribute the same amount, different amounts or nothing at all. According to our behavioural experiment, however, humans favour the equilibrium in which everyone contributes the same proportion of their endowment. We use these experimental results to highlight the non-trivial effects of inequality on cooperation, and we discuss to which extent models of evolutionary game theory can account for these effects. This article is part of the theme issue ‘Half a century of evolutionary games: a synthesis of theory, application and future directions'.

Effective cooperation leading to support of reforestation via a ‘climate public goods game’ in the Chinese collectivistic society

“…Rand, Arbesman and Christakis, 2011;Szolnoki and Perc, 2016). We do not witness some players withdrawing from the cooperative equilibrium by substantially decreasing their contribution, expecting the co-player to make up for their missing contributions at the following iterations of the game (Wang et al, 2023). Throughout recent times, the sensibility of the population has increased towards topics related to pollution (Wike and Stokes, 2016).…”

“…Secondly, Chinese subjects have usually fared low in contribution amounts in game theory experiments (Hong, Wyer and Fong, 2008). However, in this case, the participants invested an average of 2 points out of 4 available, which is not bad considering the coordination effort necessary in any PGG (Wang et al, 2023). Thirdly, the uncertainty and ambiguity of T2 and T3, which bring forward in time the likeliness to benefit from the cooperation efforts, should induce in the players a higher sense of risk aversion behaviour (Dreber et al, 2015).…”

“…As it is often the case, a limitation to the state of the art is posed by the fact that it has been conducted mainly in Western, so-called WEIRD countries (Henrich, Heine and Norenzayan, 2010), except for at least four studies (known to us) run in China (Dong et al, 2021;Kline et al, 2018;Wang et al, 2023;Wang et al, 2020). When it comes to understanding the worldwide willingness to cooperate in global issues like climate change, it is necessary to examine the replication of findings in Eastern countries, especially those that have been harshly impacted by environmental issues in recent years due to a delayed industrial revolution.…”

Half a century of evolutionary games: a synthesis of theory, application and future directions

“…Wang et al . [ 28 ] combine modelling and behavioural experiments with human participants to study public goods games with inequality in the participants' wealth or productivity. They find that a naïve application of the evolutionary models with random initial conditions often fails to produce the observed pattern in the experiments, while the accuracy of predictions remarkably improves once real-world initial conditions are implemented in the models.…”