Peer pressure induced punishment resolves social dilemma on interdependent networks

Effects of higher-order interactions on the evolution of cooperative behavior in hyperbolic scale-free network

This study proposes an innovative hypergraph model to explore the effects of higher-order interactions on the evolution of cooperative behavior in a hyperbolic scale-free network. By adjusting the heterogeneity coefficient and clustering coefficient of the hyperbolic scale-free network, four distinct network structures with notable differences can be obtained. We then map pairwise and three-way interactions to 2-hyperedges and 3-hyperedges, constructing a hypergraph model with higher-order interactions. Our findings reveal that when the proportion of three-way interactions exceeds a critical threshold, cooperative tendencies exhibit explosive growth, leading to a bistable phenomenon of coexisting cooperation and defection. The system's average degree significantly influences the critical mass of initial cooperators needed to maintain stable cooperative behavior. The network structure shows complex, non-linear effects on cooperation. In low-conditions, increasing heterogeneity acts to suppress the appearance of bistable phenomena, while in high clustering conditions, it acts to promote. Increasing clustering tends to suppress the appearance of bistable phenomena in both low and high heterogeneity conditions. Furthermore, the effects of heterogeneity, clustering, and noise factors on cooperation are non-monotonic, exhibiting inverted U-shaped patterns with critical transition points. These findings provide new theoretical perspectives for understanding diverse cooperation patterns in real-world scenarios and suggest the need for dynamic, context-specific approaches when designing strategies to promote cooperation.

The impact of dynamic linking on cooperation on complex networks

In complex social systems, individual relationships and the surrounding environment are constantly changing, allowing individuals to interact on dynamic networks. This study aims to investigate how individuals in a dynamic network engaged in a prisoner's dilemma game adapt their competitive environment through random edge breaks and reconnections when faced with incomplete information and adverse local conditions, thereby influencing the evolution of cooperative behavior. We find that random edge breaks and reconnections in dynamic networks can disrupt cooperative clusters, significantly hindering the development of cooperation. This negative impact becomes more pronounced over larger time scales. However, we also observe that nodes with higher degrees of connectivity exhibit greater resilience to this cooperation disruption. Our research reveals the profound impact of dynamic network structures on the evolution of cooperation and provides new insights into the mechanisms of cooperation in complex systems.

Stigma of coronavirus disease 2019 among hospitalized children and their parents: A prospective cohort study

BACKGROUND

The stigma associated with coronavirus disease 2019 (COVID-19) is a global problem that causes psychosomatic distress, including depression, anxiety, and loneliness. However, few studies have investigated the stigma of COVID-19 and the associated mental health impact on children or parents.

METHODS

We conducted a prospective cohort study at the National Center for Child Health and Development in Tokyo, Japan, between November 2021 and October 2022. Children (4-17 years of age) with COVID-19 and parents of hospitalized children (0-17 years of age) with COVID-19 were enrolled in the study. Children with special health-care needs were excluded. The questionnaires on stigma and mental health (depression, anxiety, and loneliness) were administered during hospitalization and at the 1 month follow-up evaluation after discharge.

RESULTS

During the study period, 47 children and 111 parents were included. Thirty-eight children (81%) and 105 parents (95%) answered the questionnaires at the 1 month follow up, respectively. Approximately 70% of participants were categorized as a high-stigma group. In children, subjective stigma was associated with loneliness during hospitalization (mean difference [MD] 2.32; 95% confidence interval [CI], 0.11-4.52) and depression at the 1 month follow up (MD 2.44; 95% CI, 0.40-4.48). In parents, presumed stigma was associated with depression, anxiety, and loneliness at 1 month follow up (MD 2.24, 1.68, and 1.15; 95% CI, 0.58-3.89, 0.11-3.25, and 0.08-2.21).

CONCLUSION

Our findings suggest that the stigma associated with COVID-19 continues to affect mental health for more than a month after discharge, and the effects of stigma on mental health differed between the children and parents.

The coordination of collective and individual solutions in risk-resistant scenarios

ABSTRACT

Human societies are constantly coping with global risks. In the face of these risks, people typically have two options, that is, to respond together as a whole (collective solution) or to respond independently (individual solution). Based on these two solutions, individuals have a variety of behavioral strategies. On the other hand, various regulatory bodies supported by the population limit people's choices and punish individuals who do not contribute to collective solutions. So with different risks, how do the two solutions, the various individual strategies, and the constraints from regulators affect the group's response to risk? This paper proposes an extended public goods game model involving opportunists and the regulator to explore the effectiveness of collective and individual solutions against risks. The results show that requiring individuals to invest more in the collective solution reduces the group' s success in resisting risk. To improve the group's ability to resist risk, investment in individual solution should be at least no less than that in collective solution. The establishment fund and punishment intensity of the regulatory agency have no significant effect on the success of collective and individual solutions. This inspires us to contemplate the role and measures of various types of authorities in coping with global risks.

Authority or Autonomy? Exploring Interactions between Central and Peer Punishments in Risk-Resistant Scenarios

Game theory provides a powerful means to study human cooperation and better understand cooperation-facilitating mechanisms in general. In classical game-theoretic models, an increase in group cooperation constantly increases people's gains, implying that individual gains are a continuously varying function of the cooperation rate. However, this is inconsistent with the increasing number of risk-resistant scenarios in reality. A risk-resistant scenario means once a group does not successfully resist the risk, all individuals lose their resources, such as a community coping with COVID-19 and a village resisting a flood. In other words, individuals' gains are segmented about the collaboration rate. This paper builds a risk-resistant model to explore whether punishment still promotes collaboration when people resist risk. The results show that central and peer punishments can both encourage collaboration but with different characteristics under different risk-resistant scenarios. Specifically, central punishment constrains the collaboration motivated by peer punishment regardless of risk, while peer punishment limits the collaboration induced by central punishment only when the risk is high. Our findings provide insights into the balance between peer punishment from public autonomy and central punishment from central governance, and the proposed model paves the way for the development of richer risk-resistant models.