The Emergence of Relationship-based Cooperation.

Area of Science:

• Evolutionary Game Theory
• Social Network Analysis
• Behavioral Economics

Background:

• Cooperation is crucial for social structures, but its emergence, especially relationship-based cooperation, remains complex.
• Existing models often overlook the role of social ties and individual preferences in cooperation dynamics.

Purpose of the Study:

• To investigate the emergence of relationship-based cooperation by integrating tie strength and homophily into an evolutionary model.
• To analyze the impact of internal social bond strength on the prevalence of cooperative strategies.

Main Methods:

• Developed an agent-based model with four player types: prosocialists, antisocialists, egoists, and altruists.
• Incorporated tie strength based investment preference and homophily (similarity) into the model.
• Simulated evolutionary dynamics under varying network structures and strategy updating rules.

Main Results:

• Relationship-based cooperation (prosocialists) is favored when individuals have stronger ties with similar types.
• Strengthening internal bonds within strategic clusters enhances the competitiveness of prosocialists.
• The model's findings are robust across different initial conditions, network structures, and updating rules.

Conclusions:

• Homophily and tie strength are key drivers for the emergence of relationship-based cooperation.
• Internal social cohesion within groups significantly promotes cooperative behaviors.
• The proposed framework provides a theoretical basis for understanding cooperation in real-world social networks.