金融机构通过相互拆借、持有共同资产等行为相互影响，构成了一个不断演化的复杂系统。与此同时，伴随着金融危机的频频上演，人们逐渐意识到金融系统的脆弱性。复杂网络为我们研究金融系统性风险提供了有效的分析工具，它可以对金融系统进行建模，捕捉金融机构之间的复杂关系，并揭示风险是如何在金融机构之间进行传播。

然而伴随着金融行业的发展，金融机构之间的交互愈发频繁，金融创新层出不穷，金融系统的复杂性进一步提升，对金融系统性风险的研究仍是一项挑战。随之而来的另一项挑战是系统性风险和收益的权衡：屡次发生的金融危机也让监管政策不断加码，但严格的监管政策也让人们质疑是否让金融系统丧失了收益与效率。针对这些问题和挑战，本文构建了内生银行网络模型，通过这种时序的、动态的复杂网络对金融系统性风险展开研究。

本文首先分析了内生银行网络的拓扑结构以及演化特征，研究发现在银行资产规模服从帕累托分布的情形下，网络连边数量逐渐降低，并演化出与实证相符的“核心-外围”结构。其次，文章基于风险来源分析了内生银行网络所面临的系统性风险。从实验结果来看，无论是负债端还是资产端的冲击提升，均会导致更高的系统性风险。研究结果重点强调了银行间网络的“稳健仍脆弱”特征，当冲击较低时，银行可以通过相互拆借补充流动性，银行网络体现出分担风险的能力，但是随着冲击强度的提升，系统性风险迅速提高，银行网络的角色从分担风险转变为传播风险，银行的倒闭将会使得风险沿着拆借链条进行扩散，最终加剧整个系统的风险。最后，文章以资本充足率和宏观审慎监管作为切入点，分析了监管对系统性风险与收益的影响。实验结果表明，随着资本充足率的提高，银行系统风险和收益同时下降，这表明政策制定者需要在权衡风险与收益的基础上选择合理的资本充足率。另一方面我们的实验结果强调了宏观审慎监管的必要性，宏观审慎监管有效控制了系统重要性银行的风险，同时对系统性收益的影响相对较小。

Financial institutions interact with each other through behaviors such as borrowing and holding common assets, forming an evolving complex system. At the same time, with the frequent occurrence of financial crises, people gradually realize the fragility of the financial system. Complex networks provide us with effective analytical tools for studying financial systems, modeling financial systems, capturing complex relationships between financial institutions, and revealing how risks propagate between financial institutions.

However, with the development of the financial industry, the interaction between financial institutions has become increasingly frequent, financial innovation has emerged endlessly, and the complexity of the financial system has further increased. The study of systemic financial risks remains a challenge. Another challenge that comes with it is the trade-off between systemic risk and returns: repeated financial crises have also intensified regulatory policies, but strict regulatory policies have also raised questions about whether the financial system has lost its returns and efficiency. In response to these issues and challenges, this article constructs an endogenous banking network model and conducts research on financial systemic risk through this temporal and dynamic complex network.

This article first analyzes the topology and evolutionary characteristics of endogenous banking networks. The study found that in the case where the size of bank assets follows a Pareto distribution, the number of network edges gradually decreases and evolves into a "core-periphery" structure that is consistent with empirical evidence. Secondly, the article analyzes the systemic risks faced by endogenous banking networks based on risk sources. From the experimental results, it can be seen that the increase in shock on both the liability and asset sides will lead to higher systemic risk. The research results emphasize the "robust yet fragile" characteristics of interbank networks. When the shock is lower, banks can supplement liquidity through mutual borrowing, and the bank network demonstrates the ability to share risks. However, as the shock intensity increases, systemic risks rapidly increase, and the role of the banking network shifts from sharing risks to spreading risks. Bank failures will cause risks to spread along the borrowing chain, ultimately exacerbating the systemic risk. Finally, the article takes capital adequacy ratio and macro prudential supervision as entry points to analyze the impact of regulation on systemic risk and returns. The experimental results indicate that as the capital adequacy ratio increases, both the risk and return of the banking system decrease, indicating that policymakers need to choose a reasonable capital adequacy ratio based on trading off between risk and return. On the other hand, our experimental results emphasize the necessity of macroprudential regulation, which effectively controls the risks of systemically important banks while having a relatively small impact on systemic returns.