This paper proposes a tractable framework to analyze fiscal space and the dynamics of government debt, with a possibly binding zero lower bound (ZLB) constraint. Without the ZLB, a greater primary deficit unambiguously raises debt. However, debt need not explode: When R G - φ, where φ is the...

We estimate a Heterogeneous-Agent New Keynesian model with sticky household expectations that matches existing microeconomic evidence on marginal propensities to consume and macroeconomic evidence on the impulse response to a monetary policy shock. Our estimated model uncovers a central role for...

We propose a general and highly efficient method for solving and estimating general equilibrium heterogeneous-agent models with aggregate shocks in discrete time. Our approach relies on the rapid computation and composition of sequence-space Jacobians--the derivatives of perfect-foresight...

We demonstrate the importance of intertemporal marginal propensities to consume (iMPCs) in disciplining general equilibrium models with heterogeneous agents and nominal rigidities. In a benchmark case, the dynamic response of output to a change in the path of government spending or taxes is...

We develop a tractable dynamic model of credit markets in which lending standards and the quality of potential borrowers are endogenous. Competitive banks privately choose their lending standards: whether to pay a cost to screen out some unprofitable borrowers. Lending standards have negative...

We present a theory of Keynesian supply shocks: supply shocks that trigger changes in aggregate demand larger than the shocks themselves. We argue that the economic shocks associated to the COVID-19 epidemic--shutdowns, layoffs, and firm exits--may have this feature. In one-sector economies...

We propose a theory of indebted demand, capturing the idea that large debt burdens by households and governments lower aggregate demand, and thus natural interest rates. At the core of the theory is the simple yet under-appreciated observation that borrowers and savers differ in their marginal...