Stability of the stochastic matching model

We introduce and study a new model that we call the {\em matching model}. Items arrive one by one in a buffer and depart from it as soon as possible but by pairs. The items of a departing pair are said to be {\em matched}. There is a finite set of classes \maV for the items, and the allowed matchings depend on the classes, according to a {\em matching graph} on \maV. Upon arrival, an item may find several possible matches in the buffer. This indeterminacy is resolved by a {\em matching policy}. When the sequence of classes of the arriving items is i.i.d., the sequence of buffer-contents is a Markov chain, whose stability is investigated. In particular, we prove that the model may be stable if and only if the matching graph is non-bipartite

Ricardian equivalence and the intertemporal Keynesian multiplier

We show that Keynesian multiplier effects can be obtained in dynamic optimizing models if one combines both price rigidities and a "non Ricardian" framework where, due for example to the birth of new agents, Ricardian equivalence does not hold.multiplier ; Ricardian equivalence ; non Ricardian economies ; price rigidities ; Keynesian multiplier

Staggered contracts and persistence : microeconomic foundations and macroeconomic dynamics

We develop in this article a new form of wage contracts similar in spirit to those developed by Calvo (1983), and integrate these contracts into a dynamic stochastic grneral equilibrium model. Rational wage setting by utility maximizing trade-unions is explicitly modelled. We derive the optimal wage contracts, and compute the dynamic macroeconomic response to monetary shocks. It is shown that, unlike in most traditional models, this response can display strong persistence, a hump shaped response and positive autocorrelations in output and employment variations. All these results are obtained in a model with explicit closed-form solutions.Persistence, Staggered wages, Wage contracts

Competitiveness, market power and price stickiness: A paradox and a resolution

Are prices less sticky when markets are more competitive? Our intuition would naturally lead us to give an affirmative answer to that question. But we first show that DSGE models with staggered price or wage contracts have actually the opposite and paradoxical property, namely that price stickiness is an increasing function of competitiveness. To eliminate this paradox, we next study a model where monopolistic competitors choose prices optimally subject to a cost of changing prices as in Rotemberg (1982a,b). For a given cost function, we find the more intuitive result that more competitiveness leads to more flexible prices.sticky prices ; Calvo prices ; cost of changing prices

The fiscal theory of the price level puzzle: A non Ricardian view

The fiscal theory of the price level says that the price level can be made determinate if the government uses fiscal policies such that government liabilities explode unless the price in the first period is at the "right" level. The policy implications are disturbing, as they call for rather adventurous fiscal policies. We show that these disturbing policy implications are specific to the "Ricardian" models that have been used to develop the theory. By moving to "non Ricardian" models we see that price determinacy is consistent with reasonable fiscal policies.fiscal theory of the price level ; fiscal policy ; global determinacy ; monetary policy

Dynamic models with non clearing markets

Abstract This article studies a new class of models which synthesize the two traditions of general equilibrium with nonclearing markets and imperfect competition on the one hand, and dynamic stochastic general equilibrium (DSGE) models on the other hand. This line of models has become a central paradigm of modern macroeconomics for at least three reasons: (a) it displays solid microeconomic foundations, (b) it is a highly synthetic theory, which combines in a unified framework general equilibrium, nonclearing markets, imperfect competition, growth theory and rational expectations, (c) it is also an empirical success, leading to substantial progress towards matching real world statistics.dynamic stochastic models ; general equilibrium ; non clearing markets ; imperfect competition

Interest rate rules, inflation and the Taylor principle: An analytical exploration

The purpose of this article is to characterize optimal interest rate rules in the framework of a dynamic stochastic general equilibrium model, and notably to scrutinize the "Taylor principle", according to which the nominal interest rate should respond more than one for one to inflation. This model yields explicit solutions for the optimal rule. We find that the elasticity of response depends on numerous factors, such as the degree of price rigidity, the autocorrelation of the underlying shocks, or which measure of inflation is used. In general the optimal elasticity of the interest rate with respect to inflation needs not be greater than one.Taylor principle ; interest rate rules ; Taylor rules ; inflation ; optimal monetary policy

IS-LM and the multiplier: A dynamic general equilibrium model

We construct in this paper a dynamic general equilibrium model which displays the central features of the IS-LM model, and notably an income multiplier greater than one, so that crowding out does not occur. It appears that the key to this result is the conjunction of two features of our model: price rigidities (as is usually expected), but also a non-Ricardian economy.IS-LM ; DSGE models ; Keynesian multiplier ; crowding out ; non-Ricardian economies

Interest rate rules and global determinacy: An alternative to the Taylor principle

A most wellknown determinacy condition on interest rate rules is the "Taylor principle", which says that nominal interest rates should respond more than hundred percent to inflation. Unfortunately, notably because interest rates must be positive, the Taylor principle cannot be satisfied for all inflation rates, and as a consequence global determinacy may not prevail even though there exists a locally determinate equilibrium. We propose here a simple alternative to the Taylor principle, which takes the form of a new condition on interest rate rules that ensures global determinacy. An important feature of the policy package is that it does not rely at all on any of the fiscal policies associated with the "fiscal theory of the price level", which was so far the main alternative for determinacy.Taylor principle ; global determinacy ; interest rate rules ; Taylor rules ; fiscal theory of the price level