This paper develops a dynamic general equilibrium model with heterogeneous firms that face search complementarities in the formation of vendor contracts. Search complementarities amplify small differences in productivity among firms. Market concentration fosters monopsony power in the labor...

This paper shows the importance of technological synergies among heterogeneous firms for aggregate fluctuations. First, we document six novel empirical facts using microdata that suggest the existence of important technological synergies between trading firms, the presence of positive...

Defensive hiring of researchers by incumbent firms with monopsony power reduces creative destruction. This mechanism helps explain the simultaneous rise in R&D spending and decline in TFP growth in the US economy over recent decades. We develop a simple model highlighting the critical role of...

We document a steady decline in low-skilled immigration that began with the onset of the Great Recession in 2007, which was associated with labor shortages in low-skilled service occupations and a decline in the skill premium. Falling returns to high-skilled jobs coincided with a decline in the...

We study the causal effects and policy implications of global supply chain disruptions. We construct a new index of supply chain disruptions from the mandatory automatic identification system data of container ships, developing a novel spatial clustering algorithm that determines real-time...

We examine the rise of dark shipping – oil tankers disabling AIS transceivers to evade detection – amid Western sanctions on Iran, Syria, North Korea, Venezuela, and Russia. Using a machine learning-based ship clustering model, we track dark-shipped crude oil trade flows worldwide and detect...

We propose a new method for solving high-dimensional dynamic programming problems and recursive competitive equilibria with a large (but finite) number of heterogeneous agents using deep learning. The "curse of dimensionality" is avoided due to four complementary techniques: (1) exploiting...

A central bank digital currency, or CBDC, may provide an attractive alternative to traditional demand deposits held in private banks. When offering CBDC accounts, the central bank needs to confront classic issues of banking: conducting maturity transformation while providing liquidity to private...

We present a general framework for Bayesian estimation and causality assessment in epidemiological models. The key to our approach is the use of sequential Monte Carlo methods to evaluate the likelihood of a generic epidemiological model. Once we have the likelihood, we specify priors and rely...

We argue that social and political risk causes significant aggregate fluctuations by changing workers' bargaining power. Using a Bayesian proxy-VAR estimated with U.S. data, we show how distribution shocks trigger output and unemployment movements. To quantify the aggregate importance of these...