Firm-bank linkages and optimal policies after a rare disaster

We study optimal government support following a rare disaster that creates heterogeneous firm liquidity needs. Firms' increase in debt reduces their output due to moral hazard. Banks are subject to a minimum capital requirement that limits deposit insurance costs upon bad aggregate shocks. Without government support, firms' moral hazard and banks' funding frictions reinforce each other amplifying output losses. Optimal support is implemented with firm-specific transfers combined with the provision of aggregate risk insurance through a capital requirement relaxation and a public preferred equity stake in banks. Our results shed light on suboptimality features in the actual policy responses to Covid-19 lockdowns.

Global DSGE models

We introduce our GDSGE framework and a novel global solution method, called simultaneous transition and policy function iterations (STPFIs), for solving dynamic stochastic general equilibrium models. The framework encompasses many well-known incomplete markets models with highly nonlinear dynamics such as models of financial crises and models with rare disasters including the current COVID-19 pandemic. Using consistency equations, our method is most effective at solving models featuring endogenous state variables with implicit laws of motion such as wealth or consumption shares. Finally, we incorporate this method in an automated and publicly available toolbox that solves many important models in the aforementioned topics, and in many cases, more efficiently and/or accurately than their original algorithms. © 2023 Elsevier Inc.

Global DSGE Models

We introduce our GDSGE framework and a novel global solution method, called simultaneous transition and policy function iterations (STPFIs), for solving dynamic stochastic general equilibrium models. The framework encompasses many well-known incomplete markets models with highly nonlinear dynamics such as models of financial crises and models with rare disasters including the current COVID-19 pandemic. Using consistency equations, our method is most effective at solving models featuring endogenous state variables with implicit laws of motion such as wealth or consumption shares. Finally, we incorporate this method in an automated and publicly available toolbox that solves many important models in the aforementioned topics, and in many cases, more efficiently and/or accurately than their original algorithms.