Recent supply disruptions catapulted the issue of risk in global supply chains (GSCs) to the top of policy agendas and created the impression that shortages would have been less severe if GSCs were either shorter and more domestic, or more diversified. But is this right? We start our answer by...

Using textual analysis of earnings conference calls, we quantify firms' supply chain risk and its sources. Our proxy for supply chain risk exhibits large cross-sectional and time-series variation that aligns with reasonable priors and is unprecedently high during the Covid-19 pandemic. In...

We characterize what features make supply chains more resilient. Using new data on the universe of firm-to-firm transactions from an Indian state, we identify firms with larger supplier risk following the Covid-19 lockdowns. Using an event-study design we find firms with suppliers in...

This paper examines the econometric causal model for policy analysis developed by the seminal ideas of Ragnar Frisch and Trygve Haavelmo. We compare the econometric causal model with two popular causal frameworks: Neyman-Holland causal model and the do-calculus. The Neyman-Holland causal model...

This paper uses the concept of the triad census first introduced by Holland and Leinhardt, and describes several distributions on directed graphs. Methods are presented for calculating the mean and the covariance matrix of the triad census for the uniform distribution that conditions on the...

We define a general class of network formation models, Statistical Exponential Random Graph Models (SERGMs), that nest standard exponential random graph models (ERGMs) as a special case. We provide the first general results on when these models' (including ERGMs) parameters estimated from the...

Haavelmo's seminal 1943 paper is the first rigorous treatment of causality. In it, he distinguished the definition of causal parameters from their identification. He showed that causal parameters are defined using hypothetical models that assign variation to some of the inputs determining...

We study a firm that justifies its novel use of equity derivatives as a cash-flow hedging strategy. Our purpose is to understand the challenge of translating risk management theory into managerial action. Cephalon Inc., a biotech firm, bought a large block of call options on its own stock. If...

Typical value-at-risk (VAR) calculations involve the probabilities of extreme dollar losses, based on the statistical distributions of market prices. Such quantities do not account for the fact that the same dollar loss can have two very different economic valuations, depending on business...

This paper discusses the recent changes in the market for catastrophe risk. These risks have traditionally been distributed through the insurance and reinsurance systems. However, because insurance companies tend to share relatively small amounts of their cat exposures and because insurance...