Efficient partner search: Embedded firms seeking co‐operative partners

This article analyses firms’ efforts to find a suitable partner for a technology cooperation. Although more theoretical studies acknowledge that search costs are an essential part of transaction costs, empirical research on interfirm co‐operation neglects searching. This paper explicitly addresses this lacuna. Hypotheses on the search behavior of firms are derived by applying considerations of transaction cost economics and arguments concerning the social embeddedness of firms to a search model widely used in economics. It is argued that on the one hand the problem potential of co‐operation, which is determined by the co‐operation's volume and the involved relation‐specific investments and uncertainty, affects the benefits a firm can gain from searching. On the other hand, the social embeddedness of a firm influences the costs of searching. Further, I consider the size and homogeneity of the pool of potential partners in the analysis. The derived hypotheses are tested on a dataset of 94 technology cooperations within five Dutch multinationals. The results clearly show that transaction cost economics does explain the search efforts of firms. In addition, I find evidence that the social embeddedness also affects searching.     

Does migration cost influence cooperation among success-driven individuals?

Migration as an important social factor has been recently considered in evolutionary games on graphs. However, the migration-related cost is largely ignored in previous works, which may indeed influence individual migration decision in human society. Here we propose a model of the success-driven migration with migration costs where individuals decide whether to migrate or not according to the migration cost and expected payoff. We consider two different calculation schemes for the migration cost, i.e., distance-dependent and distance-independent costs, and study their effects on the evolution of cooperation in the spatial prisoner’s dilemma, respectively. It is found that although the migration cost inhibits the migration of individuals, it does not necessarily lead to the suppression of cooperation. We explain the phenomenon by investigating the spatial patterns of cooperators and defectors. Interestingly, the curves of cooperation exhibit step structures and the corresponding heuristic analysis is provided. Our work complements previous studies and deepens the understanding regarding the success-driven migration on the evolution of cooperation.     

Erratum: Betweenness Centralization for Bipartite Graphs

We address two related issues. First, we analyze the effects of risk preferences on cooperation in social dilemmas. Second, we compare social dilemmas in which outcomes represent gains with dilemmas where outcomes represent losses. We show that predictions on gain‐loss asymmetries with respect to conditions for cooperation crucially depend on assumptions concerning risk preferences. Under the assumption of risk aversion for gains as well as losses together with an assumption of decreasing absolute risk aversion, conditions for cooperation are less restrictive if outcomes represent losses than if outcomes represent gains. Conversely ‐ and counterintuitively ‐ under the assumption of S‐shaped utility, conditions for cooperation are more restrictive if outcomes represent losses than if outcomes represent gains. We provide an experimental test of such predictions. Only a minority of subjects behaves consistent with the assumption of S‐shaped utility. Furthermore, we find no empirical evidence for a general difference between cooperation in social dilemmas in which outcomes represent gains and dilemmas where outcomes represent losses. We do find evidence that risk preferences affect cooperation rates.     

Evolution of shame as an adaptation to social punishment and its contribution to social cohesiveness

Feelings of shame are common among humans although shameless individuals do not seem to be handicapped in achieving social success in life. What then is the adaptive value of shame? How can shame have evolved? Here I simulate shame as the emotion that induces an increase in pro‐social behavior after receiving social punishment. Simulations with the agent‐based model, Sociodynamica, show that shame is evolutionary stable in a context of individual selection, without the need for including group selection as an evolutionary force. The adaptive advantage of shame is based on the fact that it increases flexibility to the shameful individual, allowing it to act selfish if the probabilities of being punished are low and achieving a reduction in the costs of social punishment when frequent punishment is likely. The results show that shame, together with pro‐social punishment and social cooperation, produce a fluctuating dynamics of social cooperation, achieving long periods where the populations stabilizes pro‐social behavior interspersed with periods where selfish behavior predominates. This temporal stabilization of pro‐social behavior might provide societies with sufficient time to build institutions that might stabilize sustainable pro‐social behavior. © 2008 Wiley Periodicals, Inc. Complexity, 2008     

基于演化博弈的大运河文化带城市间合作发展策略研究

目前我国正向纵深推进大运河文化带建设,合作发展是推进其建设的重要手段。文章引入经济环境、城市间资源互补性、收益分配比例、机会主义收益、惩罚成本等影响因子,运用演化博弈研究大运河文化带沿线城市间合作的形成机制。结果表明良好的宏观经济环境或城市间资源互补性强时,带来高合作超额收益,从而提高城市间向合作演化的可能性;机会收益与惩罚成本之间的差额越小,越能提高合作可能性;相反,合作成本限制了双方的合作;此外,超额收益在城市间的配比影响合作,且影响方向取决于双方投入成本与收益分配比例。因此,当前亟需政府采取各种政策鼓励城市间,特别是资源互补性强的城市间利用良好的经济建设环境加强合作,同时提高监查力度。合作城市在合作中要重视诸如利益分配、违约惩罚机制等管理机制的设计。     

Implementation of weighted values in hierarchical and horizontal cooperation structures

This paper studies a non-cooperative mechanism implementing a cooperative solution for a situation in which members of a society are subdivided into groups and/or coalitions and there is asymmetry among the individuals of the society. To describe hierarchical and horizontal cooperation structure simultaneously, we present unified classes of games, the games with social structure, and define a weighted value for these games. We show that our mechanism works in any zero-monotonic environment and implements the Shapley value, the weighted Shapley value, the Owen’s coalitional value, and the weighted coalitional value, in some special cases.     

Constraints on social dilemmas: An institutional approach

Many contemporary political and economic problems have attributes of social dilemmas. These dilemmas are simply characterized as settings in which individuals have a dominant strategy to not cooperate in collective action. However, this choice results in a Pareto-inferior outcome. Likewise, a dominated strategy exists that results in a Pareto-superior outcome. Where cooperation is absent, this problem has been described as ann-person prisoner's dilemma. This paper discusses the environmental problem of acid rain as such a social dilemma. Relying on a series of laboratory experimental settings, the argument is that many social dilemmas can be resolved through the construction of institutional mechanisms allowing for the coordination of the participant's joint strategies. Policy analysts in particular can profit from focusing on institutional solutions to social dilemmas.Support for the research reported in this paper was obtained from a summer research grant provided by the Dean of the Division of the Social Sciences, Rice University. This paper also benefited from contributions by Robert M. Thrall, Randy Calvert, Alphons van de Kragt and Mark Ishimatsu. All of the above are absolved of errors stemming from good advice that was ignored.     

Individual choice and reputation distribution of cooperative behaviors among heterogeneous groups

Cooperation is vital for our society, but the temptation of cheating on cooperative partners undermines cooperation. The mechanism of reputation is raised to countervail this temptation and therefore promote cooperation. Reputation microcosmically records individual choices, while cooperation macrocosmically refers to the group or averaged cooperation level. Reputation should be preferred in order to investigate how individual choices evolve. In this work, we study the distribution of reputation to figure out how individuals make choices within cooperation and defection. We decompose reputation into its mean and standard deviation and inspect effects of their factors respectively. To achieve this goal, we construct a model where agents of three groups or classes play the prisoners’ dilemma game with neighbors on a square lattice. It indicates in outcomes that the distribution of reputation is distinct from that of cooperation and both the mean and standard deviation of reputation follow clear patterns. Some factors have negative quadratic effects on reputation's mean or standard deviation, and some have merely linear effects.     

Combining evolutionary game theory and network theory to analyze human cooperation patterns

As natural systems continuously evolve, the human cooperation dilemma represents an increasingly more challenging question. Humans cooperate in natural and social systems, but how it happens and what are the mechanisms which rule the emergence of cooperation, represent an open and fascinating issue. In this work, we investigate the evolution of cooperation through the analysis of the evolutionary dynamics of behaviours within the social network, where nodes can choose to cooperate or defect following the classical social dilemmas represented by Prisoner’s Dilemma and Snowdrift games. To this aim, we introduce a sociological concept and statistical estimator, “Critical Mass”, to detect the minimum initial seed of cooperators able to trigger the diffusion process, and the centrality measure to select within the social network. Selecting different spatial configurations of the Critical Mass nodes, we highlight how the emergence of cooperation can be influenced by this spatial choice of the initial core in the network. Moreover, we target to shed light how the concept of homophily, a social shaping factor for which “birds of a feather flock together”, can affect the evolutionary process. Our findings show that homophily allows speeding up the diffusion process and make quicker the convergence towards human cooperation, while centrality measure and thus the Critical Mass selection, play a key role in the evolution showing how the spatial configurations can create some hidden patterns, partially counterbalancing the impact of homophily.     

Explaining cooperation in the finitely repeated simultaneous and sequential prisoner’s dilemma game under incomplete and complete information

Explaining cooperation in social dilemmas is a central issue in behavioral science, and the prisoner’s dilemma (PD) is the most frequently employed model. Theories assuming rationality and selfishness predict no cooperation in PDs of finite duration, but cooperation is frequently observed. We therefore build a model of how individuals in a finitely repeated PD with incomplete information about their partner’s preference for mutual cooperation decide about cooperation. We study cooperation in simultaneous and sequential PDs. Our model explains three behavioral regularities found in the literature: (i) the frequent cooperation in one-shot and finitely repeated N-shot games, (ii) cooperation rates declining over the course of the game, and (iii) cooperation being more frequent in the sequential PD than in the simultaneous PD.     

The evolution of cooperation in spatial groups

Much of human cooperation remains an evolutionary riddle. There is evidence that individuals are often organized into groups in many social situations. Inspired by this observation, we propose a simple model of evolutionary public goods games in which individuals are organized into networked groups. Here, nodes in the network represent groups; the edges, connecting the nodes, refer to the interactions between the groups. Individuals establish public goods games with partners in the same group and migrate among neighboring groups depending on their payoffs and expectations. We show that the paradigmatic public goods social dilemma can be resolved and high cooperation levels are attained in structured groups, even in relatively harsh conditions for cooperation. Further, by means of numerical simulations and mean-field analysis, we arrive at the result: larger average group size and milder cooperation environment would lead to lower cooperation level but higher average payoffs of the entire population. Altogether, these results emphasize that our understanding of cooperation can be enhanced by investigations of how spatial groups of individuals affect the evolution dynamics, which might help in explaining the emergence and evolution of cooperation.     

Incorporating the information from direct and indirect neighbors into fitness evaluation enhances the cooperation in the social dilemmas

We propose an improved fitness evaluation method to investigate the evolution of cooperation in the spatial social dilemmas. In our model, a focal player’s fitness is calculated as the linear combination of his own payoff, the average payoffs of direct and indirect neighbors in which two independent selection parameters (α and β) are used to control the proportion of various payoff contribution to the current fitness. Then, the fitness-based strategy update rule is still Fermi-like, and asynchronous update is adopted here. A large plethora of numerical simulations are performed to validate the behaviors of the current model, and the results unambiguously demonstrate that the cooperation level is greatly enhanced by introducing the payoffs from the surrounding players. In particular, the influence of direct neighbors become more evident when compared with indirect neighbors since the correlation between focal players and their direct neighbors is much closer. Current outcomes are significant for us to further illustrate the origin and emergence of cooperation within a wide variety of natural and man-made systems.     

Rawlsian altruism with perfect discrimination leads to social efficiency

Recent studies draw attention on the highly specialized capacity of human beings in recognizing altruists versus cheaters in social interactions. These results hint at the existence of specialized abilities that support discriminating behavior in strategic interactions. In this paper, we explore the implications of discriminating behavior in the study of the indirect evolutionary selection of selfish versus altruistic motivations in the context of generic 2×2 base games, and in particular for coordination and cooperation scenarios. We find that inequality averse (Rawlsian) altruism can enforce under rather general conditions socially optimal outcomes, including cases where selfishness cannot, such as in prisoner’s dilemmas. Inequality seeking (Nietzschian) altruism in no case improves upon Rawlsian altruism in terms of social optimality of outcomes, and often does worse. In the cooperation scenario in particular, Nietzschean altruism never manages to implement the cooperative outcome. Under perfect discrimination, moreover, inequality averse (Rawlsian) altruism often evolves at the expense of selfishness. These results suggest that the development of sophisticated discrimination abilities may be strongly adaptive in supporting fairness-oriented forms of pro-sociality in humans in the context of social dilemmas and coordination problems.     

Strategic capability investments and competition for supply contracts

Suppliers often make proactive investments to strategically position themselves to win contracts with a large buyer. Such investments reduce the suppliers’ variable costs of serving the buyer’s demand. We show that an auction mechanism does not always benefit the buyer, the supply chain, or the society. We identify scenarios where the buyer can implement the supply chain and socially optimal solution by committing to a bilateral relationship with fair reimbursement, and forgoing the benefits of competition altogether. We explore the role of commitment by the buyer (to a procurement mechanism) and by the suppliers (to an investment level) by analyzing different timing games under symmetric and asymmetric information about suppliers’ types. We show that it never benefits anyone for the suppliers to commit first. Equilibrium investments and cost structures depend upon the buyer’s bargaining power (opportunity cost). However, the winning supplier’s investments are almost always below the supply chain optimal level.     

Cooperation in harsh environments and the emergence of spatial patterns

This paper concerns the confluence of two important areas of research in mathematical biology: spatial pattern formation and cooperative dilemmas. Mechanisms through which social organisms form spatial patterns are not fully understood. Prior work connecting cooperation and pattern formation has often included unrealistic assumptions that shed doubt on the applicability of those models toward understanding real biological patterns. I investigated a more biologically realistic model of cooperation among social actors. The environment is harsh, so that interactions with cooperators are strictly needed to survive. Harshness is implemented via a constant energy deduction. I show that this model can generate spatial patterns similar to those seen in many naturally-occuring systems. Moreover, for each payoff matrix there is an associated critical value of the energy deduction that separates two distinct dynamical processes. In low-harshness environments, the growth of cooperator clusters is impeded by defectors, but these clusters gradually expand to form dense dendritic patterns. In very harsh environments, cooperators expand rapidly but defectors can subsequently make inroads to form reticulated patterns. The resulting web-like patterns are reminiscent of transportation networks observed in slime mold colonies and other biological systems.     

Trust,assurance, and inequality: A rational choice model of mutual trust 1

The rational choice approach to trust has three problems: it has not explicitly explained findings verified in social psychological study of trust; it stands on a limited assumption of asymmetric relationship between a truster and a trustee; and it has not dealt with situations in which a rich person encounters a poor person. We build a game theoretic model of mutual trust to solve these problems. Then we analyze an equilibrium of the model and derive some implications from it. That is, the ratio between the transaction costs and the opportunity costs affects actor' trustfulness; a more trustworthy actors finds it easier to leave his/her group in search of higher returns; and a rich actor is more willing to trust his/her counterpart than a poor actor.     

Does cooperation in auditing matter? A comparison of a non-cooperative and a cooperative game model of auditing

A game model of auditing including internal control investigation and substantive testing is analysed as a non-cooperative game. It is shown that in order for the presumed socially desirable outcome of high and honest effort by all to be obtained, it is necessary to adjust the cost structure to ameliorate the costs of not-qualifying erroneous accounts if the auditor can prove he or she has worked hard. Comparison with a cooperative game analysis of the model shows that there is a region of parameters where both cooperative and non-cooperative versions of the game lead to this socially desirable outcome. The significance of this result is that whilst society expects an ‘independent’ auditor not to cooperate with the auditee, the practical realities of auditing require a considerable degree of cooperation. This leads to an ‘expectations gap’ between what society expects and what actually happens, except in those cost regions where both the cooperative and non-cooperative versions of the audit game lead to the same solution.     

Modelling a social dilemma of mode choice based on commuters’ expectations and social learning

This study attempts to apply an agent-based approach to modelling a social dilemma of travel mode choice considering psychological and sociological aspects. A traveller is modelled to have expectations, which shows the traveller’s beliefs about the influence of other group members on his action, as decision-making rules. Social interaction using a group-based interaction is hypothesized to be important. We apply an imitation game based on social learning mechanisms to the model. Two kinds of mechanism are used: payoff-biased and conformist transmission. The model reveals the conditions that make cooperation as a possible outcome are optimistic bandwagon expectations, group-based interactions, and strong conformist transmissions.     

Structural cohesion and embeddedness in two-mode networks

The detection of structural cohesion is a key utility of social network analysis, but little work has been done to refine the detection of structural cohesion in two-mode networks. Most work on cohesion in two-mode networks either: (1) attempts to detect cohesion in such networks using one-mode projections (which can be problematic for reasons we discuss); or (2) focuses on restrictive substructures like bi-cliques to identify cohesive subgroups. We propose a new strategy for two-mode networks that follows the general reasoning of approaches to detecting structural cohesion in one-mode networks. Our approach identifies the number of actors from one node set that may be removed before disconnecting actors in the opposite set. We also develop a definition of embeddedness that draws on Moody and White’s hierarchical nesting approach.     

Innovation governs everything eventually: Extensions of the DeGroot model

We study the DeGroot model for continuous opinion dynamics under the influence of innovations. In the original model, individuals’ opinions, after given their initial values, evolve merely according to the given learning topology. The main contribution of this paper is that external innovation effects are introduced: each individual is given the opportunity to change her opinion to a randomly selected opinion according to a given distribution on the opinion space and then the external opinion is either adapted by the individual, or combined into her learning process. It turns out that all the classical results of the DeGroot model are violated in this new model. We prove that convergence can still be guaranteed in the expectation sense, regardless of the learning topology. We also study the steady distributions of opinions among the society and the time spent to reach a steady state by means of Monte-Carlo simulations.