Faced with the problem of pricing complex contingent claims, investors seek to make their valuations robust to model uncertainty. We construct a notion of a modeluncertainty-induced utility function and show that model uncertainty increases investors' effective risk aversion. Using this utility...

We consider fundamental questions of arbitrage pricing arising when the uncertainty model is given by a set of possible mutually singular probability measures. With a single probability model, essential equivalence between the absence of arbitrage and the existence of an equivalent martingale...

We show that nearly 100 percent of the U.S. equity premium is earned over a window around the opening hours of European markets when U.S. cash markets are closed. We explore two potential complementary explanations. First, consistent with predictions from dealer inventory risk models, we find...

We propose a measure for systemic risk: CoVaR, the value at risk (VaR) of financial institutions conditional on other institutions being in distress. We define an institution’s (marginal) contribution to systemic risk as the difference between CoVaR and the financial system’s VaR. From our...

The present paper considers a class of general equilibrium economics when the primitive uncertainty model features uncertainty about continuous-time volatility. This requires a set of mutually singular priors, which do not share the same null sets. For this setting we introduce an appropriate...

We reconsider the microeconomic foundations of financial economics under Knightian Uncertainty. In a general framework, we discuss the absence of arbitrage, its relation to economic viability, and the existence of suitable nonlinear pricing expectations. Classical financial markets under risk...

The 2007-09 financial crisis highlighted the vulnerability of financial institutions linked by a complex web of credit default swap (CDS) contracts, sparking a wave of regulatory changes to the structure of the market. In this paper, we provide broad evidence on the evolution of the CDS market...

Stablecoins and money market funds both seek to provide investors with safe, money-like assets but are vulnerable to runs in times of stress. In this paper, we investigate similarities and differences between the two, comparing investor behavior during the stablecoin runs of 2022 and 2023 to...