Fixed point theorems are the standard tool used to prove the existence of equilibria in mathematical economics. This paper shows how to prove a slight generalization of Brouwer's and Kakutani's fixed point theorems using the familiar techniques of drawing and shifting curves in the plane and is,...

The paper examines some issues linked to the integration of market power in general equilibrium. The first part reviews the different existing approaches: subjective and objective, in terms of quantities and in terms of prices. The second part presents a semi-competitive model, based on a sector...

The paper examines some issues linked to the integration of market power in general equilibrium. The first part reviews the different existing approaches : subjective and objective, in terms of quantitites and in terms of prices. The second part presents a semi-competitive model, based on a...

In this paper, from the excess utility function we obtain a binary relation in the social weights space and then, for an infinite dimensional economy, we prove the existence of equilibrium in our approach we don't suppose the existence of a demand function. Finally, we obtain a condition for the...