The analysis of horizontal mergers hinges on a tradeoff between unilateral effects and efficiency gains. The article examines the role of uncertainty (on the efficiency gains) in this tradeoff. Common wisdom is that the antitrust authorities should be very cautious about random gains. Our...

We study optimal taxation in the general extensive model: the only decision of the participants in the economy is to choose between working (full time) or staying inactive. People differ in their productivities and in other features which determine their work opportunity costs. The qualitative...

Heterogeneity is likely to be an important determinant of the shape of optimal tax schemes. This article addresses the issue in a model à la Mirrlees with a continuum of agents. The agents differ in their productivities and opportunity costs of work, but their labor supplies depend only on a...

This paper studies the welfare consequences of a vertical merger that raises rivals' costs when downstream competition is à la Cournot between firms with constant asymmetric marginal costs. The main result is that such a vertical merger can nevertheless improve welfare if it involves a...

This paper studies the welfare consequences of a vertical merger that raises rivals costs when downstream competition is à la Cournot between firms with constant asymmetric marginal costs. The main result is that such a vertical merger can nevertheless improve welfare if it involves a...

This paper studies the welfare consequences of a vertical merger that raises rivals' costs when downstream competition is a la Cournot between firms with constant asymmetric marginal costs. The main result is that such a vertical merger can nevertheless improve welfare if it involves a...