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In real life, we can find that people have some preferences when choosing routes. For example, roads with short travel time and high quality will be favored. Therefore, we introduced the concept of road impedance from the field of transportation to measure the influence of those preferences. Then, we propose a new method to define the amount of load flowing on every edge and construct a new model to simulate the dynamic process of cascading failures caused by load fluctuations after the network is disturbed. By simulating our model in three real traffic networks, we find the following phenomena and rules: First, when the flowing loads in the network have a bias, they will naturally gather on the edges with high attraction. This clustering phenomenon reduces the network robustness. Second, small-world networks are more vulnerable as loads will more easily reach the edges with high attraction. Third, the increase of edge capability decreases the robustness of the network in some cases. Through the study of a small artificial network, we find that the resurrection of edges and the characteristics of those edges are the causes of this paradox. • A cascading failure model based on traffic impedance and BRP model. • Simulation in three traffic networks and gain favorable conclusions. • Small-world networks are more vulnerable when there is a flow preference of loads. • Blindly investing resources to build the network may actually reduce its robustness. [ABSTRACT FROM AUTHOR]

In peer-to-peer interaction, people have conditions to adopt different strategies against different opponents, which is called interactive diversity. Recently, the evolution of cooperation under interactive diversity has attracted much attention, but the potential cost of maintaining interactive diversity is rarely considered. Actually, individuals may need to frequently switch their strategies between interactions with different opponents. If strategy switching is costly, individuals are likely to prefer strategies that can be maintained to strategies that require frequent changes. In other words, individuals may have behavioral inertia in their interactions with different opponents. Although some studies have found that appropriate strategy switching costs or inertia can promote cooperation under interactive identity, their role under interactive diversity remains to be further discussed. The main reason is that strategy switching costs may restrain the diversity of strategies, and the differentiation of strategies is exactly the key to cooperation under interactive diversity. In this work, we are devoted to reveal the impact of strategy switching costs on the evolution of cooperation under interactive diversity. Simulation results show that appropriate strategy switching costs are also positive under interactive diversity, but higher strategy switching costs play completely different roles in different networks. Especially, cooperation in lattice network sometimes shows a non-monotonic dependence of "first increasing, second decreasing and then increasing again" on unit switching cost. These findings are of great significance for understanding the emergence of cooperation in paired interaction under interactive diversity. • We study the effect of strategy switching costs under interactive diversity. • Small switching costs can promote cooperation on multiple networks. • Medium switching costs may hinder cooperation on lattice network. • Excessive switching costs in ER network and BA network are unbearable. • The reasons for the phenomenon differences across networks are analyzed. [ABSTRACT FROM AUTHOR]

Public resource redistribution is an important means of social income regulation, which maintains social income equality by transferring payoffs to low-income groups, usually in the form of taxes and social services. Originally studied as a means of maintaining social equality, redistribution has also been used to address social dilemmas through evolutionary game theory in recent years. However, the definition of low-income groups in previous studies is not comprehensive. They are used to studying the inequality generated by participants during the game but ignore the inequality caused by initial endowment differences. At the same time, is it beneficial to the whole that redistribution requires the rich to subsidize the poor, but leads the rich to choose defection (tax evasion, etc.)? How should the redistribution mechanism work to reduce inequality while facilitating the spread of altruistic behavior? To explore whether the redistribution mechanism can reach a balance between promoting cooperation and maintaining equality of payoffs, we develop a generic public resource redistribution framework based on heterogeneous populations by a spatial public goods game model. We control redistribution preferences for willingness to cooperate and initial endowments by parameters α and β. With a heterogeneous population, we find that helping the poor through redistribution mechanisms does not have significant positive effects and may even result in exploitation of the rich; focusing on participants' willingness to cooperate rather than total investment can promote cooperation, enhance overall payoffs and reduce inequality. • A generic redistribution framework based on heterogeneous populations has been proposed. • Helping the poor does not always have a positive effect. • Focusing on willingness to cooperate can promote cooperation and reduce inequality. [ABSTRACT FROM AUTHOR]

Prevalence of cooperation within groups of selfish individuals is puzzling in that it contradicts with the basic premise of natural selection. Grasping the force that fosters and sustains cooperative behaviors is thus of central importance for the understandings of how companies develop and how societies thrive. In this paper, by means of evolutionary game theory, we refresh the strategy updating rule to be matched with a more realistic scenario where individuals choose someone excellent as the role model and improve themselves continuously to narrow the gap. Under the force of role model, individuals adjust their instantaneous strategy with the increment δ in the next continuous M time steps. And a new role model needs to be selected unless its payoff is more than the focal player's. The computer simulation results illustrate that the self-improvement driven by role model facilitate group cooperation significantly, and the slow but persistent self-improvement performs better. Therefore, in order to achieve higher enterprise performance and build a more harmonious society, managers and government officials should spare no effort to encourage people to keep improving themselves to keep up with their role models. • A new strategy updating rule, self-improvement driven by role model updating rule is proposed. • Players make self-improvement according to the persistent choosing reference roles. • The simulation results show that a slow but persistent self-improvemnet enhances cooperation markedly. [ABSTRACT FROM AUTHOR]

Different from the previous research framework of cascading failure driven by intentional attack or random failure, this paper considers the occurrence of cascading failure from a new perspective, i.e., the spontaneous phenomenon of cascading failure. When the network changes from the low peak period to the high peak period, the global distribution of load changes, which leads to the cascading failure of the network. This phenomenon is called the spontaneous phenomenon of cascading failure. We introduce the concept of reachable region and construct a new cascading failure model, which mainly focus on how the dynamic changes of reachable area drive the dynamic behavior of cascade failures. Through simulation on two infrastructure networks, we found that: (1) The size of reachable area is positively correlated with network robustness. The larger the reachable area is, the smaller the load fluctuation of the whole network is, and the cascading failures are more easily alleviated and the network robustness is higher. But when the edge load capacity increases, the robustness of the network is not necessarily improved, which indicates the existence of capacity paradox. (2) The size of reachable area is negatively correlated with network capacity redundancy. The larger the reachable area is, the lower the capacity redundancy of the whole network will be and the less network resources will be wasted. (3) Combining with the network topology and the phenomenon of "key edge" we find that the edge with less betweenness centrality usually needs to invest higher resource protection. • We introduce the concept of reachable area and construct a new cascading failure model. • We focus on spontaneous dynamics of cascading failures. • We study the robustness of two infrastructure networks and observe an interesting phenomenon of capacity paradox. [ABSTRACT FROM AUTHOR]

Affected by geographical or social factors, human communities are organized with changeless groups for teamwork. Within groups, defection dominates because the payoffs of defectors are often higher than those of cooperators; among groups, higher cooperation level makes individuals wealthier. For the previous mechanism of evolutionary dynamics leading individuals to imitate the rich in their groups, defective strategy evolves. However, individuals who belong to different groups and have no direct interaction of interests actually could influence each other. Due to the similarity of environment, the strategies among groups have the channel and necessity of dissemination. To this end, we propose an evolutionary game model with inter-group selection of strategy. By simulations, the effects of groups' selection preference, group size, multiplier factor, imitation intensity and competition among groups on cooperative evolution in populations are studied. We find that when the group makes selection without preference, the intensity of the choice positively affects the level of cooperation; the strategy selection with preference can effectively increase the group cooperation rate. • An evolutionary game model considering inter-group selection of strategy is proposed. • A player in one group can imitate strategy of individuals in other groups. • The preference and other factors have been considered in evolutionary game. • Cooperation can be promoted effectively by our new mechanism. [ABSTRACT FROM AUTHOR]

It is known that the vaccination is essential for suppressing the periodic prevalence of an infectious disease, while the vaccination decision is influenced by external factors. Whether or not to take vaccination depends not only on the expected benefit of individual, but also on the behavior of others. Nowadays, the speed of information transmission on the social media is fast with wide range, which extremely expands the scope of imitation, but it is unknown whether it is beneficial to vaccination. Inspired by this situation, a vaccination game model on two-layer network which increases the intensity of information sharing is proposed. The vaccination game layer and the information sharing layer are established to study the interaction between individual vaccination decisions and strategic exchanges. We find that although information sharing has inhibited individual vaccination decisions to some extent, the overall scale of disease spreading in society has decreased with increasing information sharing. • A new mechanism, information sharing, in evolutionary vaccination game is introduced. • The vaccination game model in two-layer network are taken into account. • The spread of epidemics is effectively suppressed under the information sharing mechanism. [ABSTRACT FROM AUTHOR]

It is of great reference significance to exploring spatial dependence of urban traffic activities and researching internal causes of regional traffic state changes for road network optimization and residents' travel behavior analysis. Based on trajectory data of taxis in Ningbo city of China, this study calculates average driving speed of taxis in different blocks during characteristic period and generates the global Moran's I and the LISA clustering diagram. On this basis, the spatial clustering characteristics of congestion on working days and non-working days are analyzed. Furthermore, in order to further characterize the changes of congestion from the perspective of spatial migration, a method of measuring geometric displacement is adopted to describe spatio-temporal migration trend of traffic states, four indicators designed to identify urban frequently congested areas, including migration direction, angle, distance, and low-value area. The results show that the high-clustering area are located urban fringe and the low-clustering area are located at geometric center of major urban areas. Spatial–temporal migration law of low-value areas in city-center is obvious. Difference between trend is compared with non-working days, the offset and azimuth of low-value area in downtown on working days are even bigger. The accurate capture of the characteristics of congestion space migration at the urban scale will help to formulate more targeted congestion management strategies. • Quantitative analysis of azimuth,offset direction and scope change of speed. • Spatial correlation factors of real-time taxi speed. • Demonstration of spatial-temporal evolution law of low-value areas in city center. [ABSTRACT FROM AUTHOR]