Effect of financial contagion between real and financial sectors on asset bubbles: A two-layer network game approach

Understanding the mechanism of asset bubble formation is important for maintaining financial stability and healthy functioning of the economic system. With gradual emphasis on the complex characteristics of financial markets, a new perspective for analyzing the emergence of asset bubbles is emerging: how to integrate the real economy with financial markets composed of heterogeneous individuals. In this study, we propose a two-layer network game to investigate the impact of financial contagion between the real and financial sectors on asset bubbles. Among their interactions, shadow banking activities in both sectors increase the contagion risk across financial markets and construct a broader financial system. Both credit interactions and peer learning effects are captured in the network framework. Simulating relevant regulation policies, our experiments indicate that regulators should closely monitor returns on assets by setting an upper threshold. Financialization in the real sector significantly exacerbates the formation of asset bubbles, with medium-level borrowing constraints minimizing bubble dynamics most effectively. The financialization practices of mature industries should be strictly regulated, while innovative industries should be allowed moderately flexible financing practices. The degree of friction within the financial market should be flexibly calibrated for financial institutions and genuine enterprises, aiming to mitigate systemic risks in the financial market while fostering robust growth in the real economy.