We present conditions for the emergence of singularities in DGE models. We distinguish between slow-fast and impasse singularity types, review geometrical methods to deal with both types of singularity and apply them to DGE dynamics. We find that impasse singularities can generate new types of...

Policy implications are derived for an inflation-targeting central bank, whose credibility is endogenous and depends on its past ability to achieve its targets. This is done in a New Keynesian framework with heterogeneous and boundedly rational expectations. We find that the region of allowed...

We examine the nonlinear model Xt = Et F(xt+1) . Markov SSEs exist near an indeterminate steady state, X = F(X), provided F´(X)> 1. We show that there exist Markov SSEs that are E-stable, and therefore locally stable under adaptive learning, if F´(X)< -1.

We consider the stability under adaptive learning of the complete set of solutions to the model when . In addition to the fundamentals solution, the literature describes both finite-state Markov sunspot solutions, satisfying a resonant frequency condition, and autoregressive solutions depending...

This paper analyses two types of models: 1. Those based on assumptions of monetary and financial market equilibrium disturbance in line with mainstream thinking that there is self-regulating market, the units would have rational expectations, and the crisis would be a temporary phenomenon caused...

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...

Slow firm entry over the business cycle causes measured TFP to vary endogenously because incumbent firms bear shocks. Our main theorem states that imperfect competition and dynamic firm entry are necessary and sufficient conditions for these endogenous productivity fluctuations. The result...

We study the possibility of (almost) self-fulfilling waves of pessimism and selfreinforcing liquidity traps in a New Keynesian model with heterogeneous expectations. We explicitly focus on the "anchoring" of expectations that is modeled as the range of deviations from the central bank targets...

This paper uses the tools developed in the literature on dynamically incomplete markets with finite agents to study the large economy with a continuum of agents and both aggregate and idiosyncratic shocks in Krusell and Smith (1998). It establishes the existence of sequential competitive...

I develop a model of dynamic firm entry, oligopolistic competition and returns to scale in order to decompose TFP fluctuations into technical change, economic profit and markup fluctuations. I show that economic profits cause short-run upward bias in measured TFP, but this subsides to upward...