چگونه نوع دوستی کار می کند: یک مدل تکاملی از شبکه های تامین

Recently, supply networks have attracted increasing attention from the scientific community. However, it lacks serious consideration of social preference in Supply Chain Management. In this paper, we develop an evolutionary decision-making model to characterize the effects of suppliers’ altruism in supply networks, and find that the performances of both suppliers and supply chains are improved by introducing the role of altruism. Furthermore, an interesting and reasonable phenomenon is discovered that the suppliers’ and whole network’s profits do not change monotonously with suppliers’ altruistic preference, ηη, but reach the best at η=0.6η=0.6 and η=0.4η=0.4, respectively. This work may shed some light on the in-depth understanding of the effects of altruism for both research and commercial applications.

In the last decade, Supply Chain Management (SCM) has made significant strides in both theoretical and practical fronts [1], [2], [3], [4], [5] and [6]. However, how to manage relationship with suppliers (or retailers, dealers) still remains a huge challenge, since firms have to face the coexistence problem of cooperation and competition with other firms in an interdependent environment. As pointed out by Simchi-Levi et al. [1], supply chain analysis inspires new research ventures that blend operations research, game theory, and microeconomics. However, although quantitative supply chain analysis provides insight into understanding competition and cooperation among firms, there are limitations to understand the nonlinear dynamics and social impacts on free market structures [7]. SCM is the management of a network of interconnected businesses, which suggests that the complexity and adaptivity should not be ignored in a network background [8], [9], [10] and [11]. In addition, the mainstream research supposes that agents in supply chains intend to make self-maximizing decisions. These operational decisions are on the basis of agents’ optimal prediction of the future. However, these so-called “optimal” behaviors could not be easily predictable, sometimes even unbelievable when a large number of agents interact in a complex supply network. Actually, it will be crucial to examine the evolution of supply networks over an extended time horizon [7], e.g., Barabási et al. proposed an evolutionary model of social network’s time evolution [12]. Different from the rational focus on the future benefits, they behave dependently on their past behaviors. Furthermore, there are sufficient evidences indicating that firms care about their partners’ profits in the chain as well as their own, in order to keep or improve the competitiveness of the total supply chain [13]. For example, Steiner contends that business decision-making today is a mixture of altruism, self-interest, and good citizenship [14]. At the same time, many behavioral economic researchers have developed various forms of interdependent social preferences to justify experimental observations [15], [16], [17] and [18]. The main concepts of existing interpretations are based on fairness, or altruism. That is to say, people consider fairness based on relative payoffs, or how monetary payoffs are distributed among them [19], [20], [21] and [22]. Though Tooby and Cosmides [23] have argued that people may help friends who are unlikely to pay back, DeScioli and Robert empirically demonstrated that the altruism did contribute to the formation of alliance [24]. Moreover, it is also demonstrated that the existence, incentives, and effects of altruism are wildly existing in human behaviors from the perspectives of both social science and biology [25], [26], [27], [28] and [29]. In this paper, we investigated the effects of altruism on an evolving supply network: how suppliers’ altruistic decision-making mechanism affects the suppliers’ performance from the perspective of evolutionary dynamics [30]. In addition, we proposed a model to evaluate how altruism benefits supply networks, in which an evolutionary pricing mechanism is proposed under the assumption that firms are altruistic when they make decisions. The results show that suppliers have incentives to be altruistic, because the altruistic decision-making mechanism makes them better. The rest of this paper is organized as following. In Section 2, we describe some settings of our model in Section 2 and the mechanism in Section 3. After this, we present the model results and analysis in Section 4, and conclude in Section 5.

Despite the volume of research on Supply Chain Management, there is only limited attention to such “buyer–seller” relationship in supply networks in the literature. In this paper, we developed an evolutionary decision-making mechanism to characterize suppliers’ altruism supported by an agent-based model. The results show that the performances of both suppliers and supply chains are improved with considering altruistic, comparing with noncooperative scenarios. This might suggest that an agent would benefit from his own altruism decision. However, an interesting and reasonable phenomenon is that the profits of both suppliers and chains change nonlinearly with suppliers’ altruistic preference in general. Furthermore, they reach their peaks at relatively middle altruistic levels, but not simultaneously. Those findings might indicate that the suppliers have incentives to behave altruistically, but still remain competition with each other, which means a coexistence of cooperation and competition, i.e., coopetition. There are many altruistic examples in real life. A live case comes from a global executives talk [13]. Alexander Cummings, the president and Chief Operational Officer (COO) of Coca-Cola Company in Africa, recounted one of his successful altruistic decisions. In a market with high inflation and currency devaluation, They had held price for several years to maintain his growth momentum. As a result, their bottlers were struggling to make adequate returns. In order to increase their bottlers’ profits, Cummings increased the retail price, which surprisingly improved the profitability for both the company and their bottlers even though they faced a deep drop of volume and market share for six months. This paper only provides a simple start point to study the effect of altruism in supply networks, and a couple of open issues remain for the further study. First, in this paper, we focus on the effect of supplier’s altruism. Comparatively, the effect of retailers’ altruism is lack of study, and it could also be taken into account to investigate how mutual altruism impact the total profit with complex interactions between agents. Second, we only discuss a unique and constant altruism parameter in our model, however, an adaptive altruism mechanism should also be considered to see how altruism works in evolving supply networks. Finally, a supply network structure with multiple echelons, roles and rules is common in reality, so further research should pay more attention to these types of supply networks by developing applicable analysis tools.