Debt levels in the eurozone have reached new record highs. The member countries have tried to cushion the economic consequences of the corona pandemic with a massive increase in government spending. There are various calls to abolish or soften the Maastricht rules of limiting sovereign debt. The...

I characterize optimal monetary and fiscal policy in a stochastic New Keynesian model when nominal interest rates may occasionally hit the zero lower bound. The benevolent policymaker controls the short-term nominal interest rate and the level of government spending. Under discretionary policy,...

This paper characterises optimal monetary policy in an economy with endogenous firm entry, a cash-in-advance constraint and preset wages. Firms must make profits to cover entry costs; thus the markup on goods prices is efficient. However, because leisure is not priced at a markup, the...

This chapter aims to provide a hands-on approach to New Keynesian models and their uses for macroeconomic policy analysis. It starts by reviewing the origins of the New Keynesian approach, the key model ingredients and representative models. Building blocks of current-generation dynamic...

How does the need to preserve government debt sustainability affect the optimal monetary and fiscal policy response to a liquidity trap? To provide an answer, we employ a small stochastic New Keynesian model with a zero bound on nominal interest rates and characterize optimal time-consistent...

There is substantial disagreement about the consequences of the Tax Cuts and Jobs Act (TCJA) of 2017, which constitutes the most extensive tax reform in the United States in more than 30 years. Using a large-scale two-country dynamic general equilibrium model with nominal rigidities, the authors...

Did the Federal Reserves' Quantitative Easing (QE) in the aftermath of the financial crisis have macroeconomic effects? To answer this question, the authors estimate a large-scale DSGE model over the sample from 1998 to 2020, including data of the Fed's balance sheet. The authors allow for QE to...

The recently observed disconnect between inflation and economic activity can be explained by the interplay between the zero lower bound (ZLB) and the costs of external financing. In normal times, credit spreads and the nominal interest rate balance out; factor costs dominate firms' marginal...

This paper identiftes U.S. monetary and ftscal dominance regimes using machine learning techniques. The algorithms are trained and verifted by employing simulated data from Markov-switching DSGE models, before they classify regimes from 1968-2017 using actual U.S. data. All machine learning...

How does the need to preserve government debt sustainability affect the optimal monetary and fiscal policy response to a liquidity trap? To provide an answer, we employ a small stochastic New Keynesian model with a zero bound on nominal interest rates and characterize optimal time-consistent...