L’arbitrage entre équité et efficacité en matière d’emploi et de salaires est abordé de deux manières. D’une part, un modèle simple permet d’analyser les conditions qui rendent la politique de salaire minimum un instrument plus efficace de redistribution que les taxes et les transferts. Une condition nécessaire et suffisante est que la perte de bien-être associée à une hausse des taxes de un franc excède l’élasticité (en valeur absolue) de l’emploi par rapport au salaire net. D’autre part, le modèle est élargi à l’incertitude et aux marchés incomplets. Il est démontré qu’en absence d’un mécanisme adéquat de partage efficient du risque entre tous les agents (en particulier entre les actionnaires et les travailleurs) une forme de rigidité à la baisse des salaires est plus efficace au sens de Pareto.

A simple general equilibrium model of imperfect competition is introduced with special attention given to the labour market. An extended Cournot equilibrium is defined for any money wage taken as given by the producers. Under some assumptions involuntary unemployment may arise, that is unemployment whatever the given money wage. Specific examples are considered.

The purpose of this paper is to understand disequilibrium phenomena at a disaggregated level. By using data on French firms, we carry out the estimation of labor demand model with two regimes, which correspond to the Keynesian and classical hypotheses. The results enable us to characterize classical firms as being particularly good performers: they have more rapid growth, younger productive plant and higher productivity gains and profitability. Classical firms stand out, with respect to their production function, by higher growth rate of disembodied technical progress and, with respect to their accumulation behaviour, by more rapid investment and replacement rates which lead to the rejuvenation of their capital stock. But the production-employment elasticities and production-capital elasticities, as well as the accelerator, are identical for classical and Keynesian firms.