This paper is about involuntary unemployment in general equilibrium models with imperfect competition. It surveys papers written after the seminal work of d'Aspremont, Dos Santos Ferreira and Gérard-Varet (1984). This unemployment is called involuntary because it exists at any wage. It results...

It is commonly acknowledged that a larger number of trade unions is associated with a higher level of employment. We demonstrate that this belief can be wrong, i.e. that the entry of trade unions can increase the number of unemployed workers. This result is stated in a multi-sector economy in...

We investigate how imperfect competition affects the occurence and properties of endogenous business cycles with underemployment in an overlapping generations model. We consider a competitive product market in association with an imperfect labour market. The latter is presented in two variants....

In an OG model with competition à la Cournot, we show the existence of a stable 2-cylcle (in prices and employment levels) in the forward dynamics with learning.

We consider the general equilibrium of an economy with Cournot competition in the product market. In this framework, firms endowed with market power are assumed to know the true or objective demand function. However, depending on the economy's structure, the demand function varies with the size...

We study the link between involuntary unemployment and income feedback effects in a model with an imperfect product market. We provide a condition based on the demand such that full employment prevails when income feedback effects are neglected, while involuntary unemployment appears when they...

We investigate the link between "underemployment at all wages" and income feedback effects due to firms' activities in an economy with imperfect competition in the product markets. The size of income feedback effects negatively depends on the number of product markets. We strengthen a previous...

We investigate the dynamics of a cobweb model with heterogeneous beliefs, generalizing the example of Brock and Hommes (1997). We examine situations where the agents form expectations by using either rational expectations, or a type of adaptive expectations with limited memory defined from the...

We investigate the dynamics of a cobweb model with heterogeneous beliefs, generalising the example of Brock and Hommes (1997). We examine situations where the agents form expectations by using either perfect foresight, or a form of adaptive expectations with limited memory defined from the last...

While Rational Expectations have dominated the paradigm of expectations formation, they have been more recently challenged on the empirical ground such as, for instance, in the dynamics of the exchange rate. This challenge has led to the introduction of heterogeneous expectations in economic...