Economics serving society
Elena del Mercato

Elena del Mercato

PSE Professor

Associate Professor Université Paris 1 Panthéon-Sorbonne


Campus Jourdan – Maison des Sciences Economiques 106-112 Boulevard de l'Hôpital 75647 Paris Cedex 13

Building CES, 5th floor, office 518

Phone +33(0)1 44 07 83 03

Personal website
Research groups: Economic Theory
  • Game Theory
  • General Equilibrium
  • Mathematical Economics


"Markets, Equilibrium and Optimum"

Licence L3 MIASHS - in French

This course is based on the classic paradigm of general equilibrium models and the concepts of competitive equilibrium and social welfare associated with these models. It is well known that the existence of competitive equilibria and the two fundamental theorems of welfare economics are based on highly restrictive assumptions of full transaction, complete information, absence of money, absence of public goods and absence of interactions among agents. For that reason, the classical model has been modified considering these different kinds of “imperfections”. One of the topics of this course concerns externalities, that is situations where agents' decisions affect the choices of the others. In the context of general equilibrium models, the natural adaptation of the concept of competitive equilibrium leads to a concept of equilibrium à la Nash. As in the classical case, equilibrium prices reflect the individual marginal effects. But, welfare conditions à la Pareto reflect the social marginal effects. So, in general, the presence of externalities leads to sub-optimal equilibrium allocations. Several possibilities are open to recover the Pareto optimality of equilibrium allocations.

"Microeconomics 1"

Masters M1 IMMAEF and MAEF - in English

The first part of the course deals with individual decision making by consumers and producers. The second part of the course is devoted to production economies.

"General Equilibrium Theory" (with J.-M. Bonnisseau)

Masters M2 MMMEF and APE - in English

The general equilibrium theory studies the interactions among heterogeneous agents on commodity and financial markets. The course begins with an outline of the main properties of a competitive equilibrium in the classical Arrow-Debreu model (existence, efficiency, local uniqueness). The course then focuses on advanced questions arising from market imperfections and it consists of two parts:

  • "General equilibrium and Externalities (E. del Mercato)", and
  • "General equilibrium and Financial Markets (J.-M. Bonnisseau)".