The concentration of risk within financial system is considered to be a source of systemic instability. We propose a theory to explain the structure of the financial system and show how it alters the risk taking incentives of financial institutions. We build a model of portfolio choice and...

Financial networks have shown to be important in understanding systemic events in credit markets. In this paper, we investigate how the structure of those networks can affect the capacity of regulators to assess the level of systemic risk. We introduce a model to compute the individual and...

Financial institutions form multi-layer networks of contracts among each other and exposures to common assets. As a result, the default probability of one institution depends on the default probability of all the other institutions in the network. Here, we show how small errors on the knowledge...