The theory of monotone comparative statics and supermodular games is presented as the appropriate tool to model complementarities. The approach, which has not yet been fully incorporated into the standard toolbox of researchers, makes the analysis intuitive and simple, helps in deriving new...

This paper develops a theory of regular Markov perfect equilibria in dynamic stochastic games. We show that almost all dynamic stochastic games have a finite number of locally isolated Markov perfect equilibria that are all regular. These equilibria are essential and strongly stable. Moreover,...

This paper considers a general class of nonlinear rational-expectations models in which policymakers seek to maximize an objective function that may be household expected utility. We show how to derive a target criterion that is: (i) consistent with the model's structural equations, (ii) strong...

Rational expectations are often used as a strong argument against policy activism, as they may undermine or neutralize the policymaker’s actions. Although this sometimes happens, rational expectations do not always imply policy invariance or ineffectiveness. In fact, in certain circumstances...

Money managers behave strategically when competing for fund flows within relatively small groups. We study strategic interaction between two risk-averse managers in continuous time, characterizing analytically their unique equilibrium dynamic investments. Driven by chasing and contrarian...

This paper shows that absent a commitment technology, central banks can nevertheless achieve the (timeless-)optimal commitment equilibrium if they are delegated with an objective function that is different from the societal one. In a prototypical forward-looking New Keynesian model, I develop a...

In this paper we consider a Ramsey one-sector model with non-separable homothetic preferences, endogenous labour and productive external effects arising from average capital and labour. We show that indeterminacy cannot arise when there are only capital externalities but that it does when there...

We study identification in a class of linear rational expectations models. For any given exactly identified model, we provide an algorithm that generates a class of equivalent models that have the same reduced form. We use our algorithm to show that a model proposed by Benhabib and Farmer [1] is...

In this paper, we consider an aggregate overlapping generations model with endogenous labour, consumption in both periods of life, homothetic preferences and productive external effects coming from the average capital and labour. We show that under realistic calibrations of the parameters, in...

In aggregative games, each player's payoff depends on her own actions and an aggregate of the actions of all the players (for example, sum, product or some moment of the distribution of actions). Many common games in industrial organization, political economy, public economics, and...