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In real life, people often participate in regional public goods games and face the social dilemma caused by the non-exclusivity of public goods. Intervening policies are expected to alleviate the social dilemma and promote intra-regional cooperation. However, owing to the existence of the costs of policy, the marginal benefits of establishing intervening policies may be diminishing, which raises questions as to whether it is necessary to establish intervening policies on a global scale; whether partial intervention is a more economical solution. In view of this, this paper investigates the evolution of cooperation in regional public goods game in the context of a central institution selecting some regions to set up an endogenous reward and punishment policy, focusing on the effects of the proportion of selection and the methods of selection on global cooperation and total social welfare. The results show that the partial intervention is superior to the whole intervention in terms of total social welfare when the coefficient of the costs of the policy is large or when strict reward and punishment are imposed and that the partial intervention can achieve the effect of the whole intervention in terms of cooperation in many cases. For all three selection methods, i.e., random selection, degree centrality selection, and size selection, size selection is optimal in most cases. Furthermore, allowing groups in non-intervened regions to spontaneously establish or abolish the policy can greatly facilitate cooperation under all three methods. Finally, we find that the central institution's prolonged and sustained intervention is essential, and its termination will lead to serious consequences. • We explore the effect of partial intervention on global cooperation and welfare. • Groups in intervened regions establish an endogenous reward and punishment policy. • The roles of the three selection methods are discussed. • Partial intervention is more profitable than whole intervention in some cases. • Prolonged and sustained intervention is necessary. [ABSTRACT FROM AUTHOR]

Central sanctioning institution controlled by third party is a double-edged sword for the evolution of cooperation. On the one hand, the institution can protect cooperators from the exploitation of free-riders; on the other hand, a corrupt third party can cause the institution to fail, thus resulting in the collapse of cooperation. However, previous relevant studies have always explored that third parties are bribed by free-riders, and therefore forgo sanctioning free-riders. Although bribery is an important component of corruption, it is not comprehensive. In this paper, we consider third parties who embezzle public funds, which is characterized by the fact that the deterrence of sanctions remains even if corruption occurs. There is a new dilemma here, where cooperators are exploited by third parties when they are in the institution and by free-riders when out of the institution. An evolutionary game model is established to represent this dilemma, and a complex network model is constructed to represent interactions between third parties and players. We discuss the evolutionary dynamics of cooperation, trust and corrupt behaviours both in finite and infinite population, while find that players trust corrupt third parties and maintain cooperation as long as the sanction institution is sufficiently effective and the corruption rate is not very high. This work presents a novel framework for representing interactions between players and third parties, and suggests that exploitation by free-riders is less acceptable to cooperators than exploitation by third parties. [ABSTRACT FROM AUTHOR]

"Friends of friends are friends, and enemies of friends are enemies" is a well-known friendship transmission effect. In interpersonal interactions, friendship transmission may prompt individuals to imitate one partner's attitude toward another. Real human interactive networks often show a high degree of clustering and are filled with triangles. In this context, friendship-transmission-based imitation (FI) may be very frequent and play a crucial role in the flourishing of cooperation. Here, we develop an evolutionary pairwise game model and conduct simulations on small-world networks with the aim of revealing exactly how FI affects cooperation. Specifically, we add four forms of FI to a strategy update framework with interactive diversity, using two sets of parameters to control the frequency of each update method. The results show that the different FIs play very different roles. Two of them even conditionally outperform the targeted imitation with reciprocal features. Furthermore, appropriate coexistence of multiple FIs may catalyze more cooperation. This work captures potential factors influencing the evolution of cooperation in real human societies, and contributes to understanding the drivers and the barriers to human cooperation in highly clustering interactions. • We focus on the mutual influence within triangle under interactive diversity. • A well-known friendship transmission effect is introduced in cooperation evolution. • Roles of four new strategy update methods are discussed separately. • Appropriate coexistence of different methods may promote cooperation. [ABSTRACT FROM AUTHOR]

Collective action, like public goods game, often requires mechanism intervention to avoid exploitation by free-riders. Reward and punishment are two widely studied solutions, but the balance of budgets and diverse behavioral motivations need further emphasis. Here, we introduce a heterogeneous distribution system based on peer rating (PRHDS), a disguised reward and punishment mechanism under budget balancing, and consider a comprehensive range of behavioral motivations. Preliminary studies show that PRHDS has the potential to promote cooperation, but is too sensitive to random exploration. This vulnerability is attributed to the exploitation of prosocial cooperators by egoistic cooperators. Afterward, we propose three punishments for minority raters and find that two monetary punishments can compensate for the above limitation. A notable finding is that the cooperation potential at medium multipliers seems to exceed that at high multipliers. In addition, our further analysis suggests that PRHDS may perform better when strategy differentiation is considered. This study reveals the possible limitations of PRHDS as a solution to collective social dilemma, and may have some enlightening significances for seeking the countermeasures. • We study a potential solution to the collective dilemma under balancing budget. • Diverse rating motivation and strategy knowability condition are considered. • The proposed mechanism is found to be too sensitive to random exploration. • We further propose remediations for stable cooperation under noise conditions. • The existence and role of interactive diversity individuals is also discussed. [ABSTRACT FROM AUTHOR]

For many years, social diversity has been recognized as one of the important factors in the emergence of cooperation. In PGG that characterizes collective social dilemmas, the difference in individual contributions to collective output usually arises from diversity of endowments and productivity, or from heterogeneous investments, but this difference may also be caused by the unequal dependence of collective output on members. In real collective actions, individuals may not contribute homogeneous currencies or goods, but instead divide labor to complete a series of tasks. Some individuals who master critical resources and skills may have a greater impact on collective output. In this work, a heterogeneous population containing elites and ordinary people plays spatial public goods game. The peculiarity is that ordinary people can make full contributions only when there are cooperative elites within the team. Otherwise, a part of the work will not be able to be carried out, and the cooperation contributions of ordinary people will be greatly reduced. Simulations under multiple social structures consistently show that the presence of a small number of elites can greatly stabilize cooperation. On the contrary, an excess of elites undermines the stable cooperative structure between elites and ordinary people. • We consider the unequal dependence of collective output on members. • A spatial public goods game involving elites and ordinary people is proposed. • There is an optimal proportion of elites that maximizes cooperation fraction. • Optimal value is not greatly affected by parameters but interactive structure. [ABSTRACT FROM AUTHOR]

This paper extends the conformity model by introducing heterogeneous social influence into the analysis. We associate the influence of a player in the network with its degree centrality assuming that players of higher degree exhibit more social influence on its neighbors. The results show that the equilibrium level of cooperators can be dramatically enhanced if the conformity-driven players are preferentially influenced by neighbors of higher degree. We attribute this finding to two elementary mechanisms in the evolutionary process: (1) degree-based social influence facilitates the formation of strategic clusters around hubs; and (2) payoff-heterogeneity between cooperative clusters and defective clusters contributes to the promotion of cooperation. This research reveals the important role of heterogeneous social influence on the emergence of cooperation in social networks. [ABSTRACT FROM AUTHOR]

• A new reputation mechanism, heterogeneity of reputation increment driven by individual influence in evolutionary game is proposed. • Distinct from traditional reputation mechanism, our mechanism illuminates that the scale of reputation fluctuation has heterogeneity and dynamic. • Compared with the traditional reputation model, our new model promotes cooperation effectively. Cooperation is ubiquitous, but our innate selfishness greatly challenge our motivation to cooperate since natural selection favors the fittest individuals in all the ecosystems. In addition, cooperation is costly, implementing it weighs down the individual wealth and the prosperity of human society. Therefore, how to deal with social dilemma has attracted numerous scholars' attentions. Among previous researches, indirect reciprocity acts a crucial role in the promotion of cooperation. However, scholars focus more on the consistency and constancy of all the players' reputation fluctuation, and ignore its potential features, the heterogeneity and dynamic of the reputation increment. In real world, such a scenario can reflect it, for example, a famous person and a notorious person have a totally distinct reputation variation even if they have coincident actions. Inspired by aforesaid particularity of reputation variation, a new mechanism, heterogeneity of reputation increment driven by individual influence is introduced, in which players who have more payoffs than the average of their neighbors' would be more influential, and their actions would lead to a bigger scale of reputation fluctuation due to more attentions from others. Simulation results show that cooperation is facilitated effectively by our new mechanism, compared with traditional model with constant reputation variation. [ABSTRACT FROM AUTHOR]

• An adaptive coevolution mechanism of sharinng and cooperation, Temporary-Interest-Community (TIC) mechanism, is proposed. • TIC mechanism successful rescues both voluntary sharing and cooperation. • Sharing in a visionary population is more frequent and stable. Living in the environment full of competition and risk, individuals are supposed to pursue private interests. Defectors avoid the cost of cooperation and usually earn more. So defection seems to prevail in the population under natural selection. However, the costly cooperation abounds both in biological systems and human society, which attracts the interest of scholars in many fields. Income sharing is a simple and effective means of promoting cooperation. But most sharing mechanisms at present highly rely on enforcement. Sharing is always costly for the sharers, as same as cooperating. So voluntary sharing hardly survives without a reasonable evolution mechanism. In this work, we studied the coevolution of sharing and cooperation and found the failure of traditional sharing mechanisms on maintaining voluntary sharing. To rescue the voluntary sharing and cooperation, we proposed a fresh form of sharing mechanism, Temporary Interest Community (TIC) mechanism. According to our simulations, TIC mechanism successful rescues both voluntary sharing and cooperation to some extent, but it never eliminates the defection completely. Sharing is conductive to cooperation, while the development of cooperation inhibits sharing among population instead. In addition, we have also observed that sharing in a visionary population is more frequent and stable. So strengthening the memory of the group may stimulate more cooperation. [ABSTRACT FROM AUTHOR]