This short piece presents the contributions of the special issue of Games, “Pro-sociality and Cooperation”. The special issue itself contributes to the long-standing literature on this topic that remains key for the proper functioning of societies, as highlighted by recent global challenges such as the threats posed by climate change or the containment of the COVID-19 pandemic. The seven articles included in the special issue cover a number of strategic contexts and use both theory and experiments to uncover new findings on how cooperation among humans emerges and can be sustained.
Three studies investigate drivers of interactions in the well-known public goods game. Jimenez-Gomez [1
] examines cooperation when agents are linked in a network, illustrating how social pressure can foster cooperation even among fully rational agents who fear being punished after observing some agents starting to contribute to the public good. Two other studies focus on behavioral drivers beyond mere self-interest. Butz and Harbring [2
] designed an experiment to test whether revealing the identities that include a donation incentive can lead to higher voluntary contributions to a public good. The announcement of subsequent identity disclosure resulted in significantly higher contributions when the donation was costly, but it reduced contributions when the donation was costless. Finally, Suleiman and Samid [3
] reconsider some patterns behind antisocial punishment, which can hinder cooperation, using both previous and novel experimental data on public goods games. They provide evidence for revenge as a possible explanation for this phenomenon.
Another contribution that considers the role of psychological drivers is that by Andersson [4
]. The author shows that emotions can boost cooperation under a finite horizon through reputation building-like mechanisms or by reducing the necessary discount factor under an infinite horizon. However, emotions can also hamper cooperation by making players less willing to punish or more hostile when punished.
Two other papers focus on different strategic contexts. Gillet [5
] studies with an experiment whether voting for a cartel formation in a Bertrand game is a signal for cooperativeness. The main finding is that there is no systematic relation between individuals who support the cartel and the prices they choose when they decide in isolation. Brams and Kilgour [6
], instead, prove that by interchanging the payoffs in a centipede game, a unique Nash equilibrium where the two players cooperate exists. The authors also provide insights on how this finding can apply in the context of an arms race.
The Special Issue includes one methodological contribution by Medda et al. [7
]. The authors study whether individuals who participated in many laboratory experiments exhibit different degrees of pro-sociality compared to inexperienced participants. The good news is that, on average, no significant difference is detected between the two groups. Yet, if experienced participants are aware of being matched with inexperienced ones, they tend to change their behavior systematically.