Abstract: Finance is the core of modern economy. The sustained and healthy development of economy is inseparable from the stability of financial system. In this paper, we take lending relationships of different loan terms and common asset relationships of different investment cycles into consideration to construct a multilayer DebtRank model of bank-firm system. Then, based on the calculation experiment method, we investigate the systemic importance identification effect and the internal characteristics of banks and firms. The simulation results display that only a few banks and firms show systemically important characteristics in the whole bank-firm system. Specifically, these banks and firms of importance show significant homogeneity. Besides, their owner’s equity and income are mostly at high level, which is manifestly different from the “fragile” banks and firms which possess negative net assets and serious losses. Moreover, compared with the common asset relationship between banks and firms, the loan relationship plays a more indispensable role in the systemic importance identification of multilayer DebtRank model. Further, the model we construct is stable, which can reflect the characteristics of the “importance” of the system from the theoretical level, and has advantages for regulators to extract and effectively identify the banks and firms of importance to guarantee the stability of the financial system.

Key words: multilayer DebtRank model, loan relationship, common asset relationship, systemic importance