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Biography

Gaël Giraud is researcher at CNRS in economics. Ancient scholar from the Ecole Normale Supérieure (Ulm), he graduated from ENSAE and earned his Doctorate in Mathematics at the  Laboratoire d’Econométrie de l’Ecole Polytechnique. Ancient  fellow of the CORE (Louvain-la-Neuve, Belgium), his first theoretical works dealt with the modelization of  general economic equilibrium in the presence of imperfect competition ---  a question that conjugates both non-cooperative game theory and classical general equlibrium theory. More recently, he is working on a computable model of out-of-equilibrium dynamics.
He has been a scientific consultant in market finance for private banks. His works then dealt with the pricing of weather derivatives and of credit risk derivatives, as well as with portfolio optimization.
Gaël Giraud gave lectures at CORE, as well as at the ENS, at ENSAE, the Universities Louis Pasteur (Strasbourg), Paris-I and II, Ha-Noï (Viêt-Nam) and at the CCL of Sarh (Tchad).  He has published more than ten papers in international journals and taken part to around twenty international congresses.
During his civil service in Chad,  together with Pierre Landèche, Gaël Giraud founded a center for street children (http:// membres.lycos.fr/aaermc/asso.html). As a jesuit, he works today in political theology and et collaborates to the journal Projet (http://www.ceras-projet.com).

Current research

An auction for IPOs.
Given the opacity and confusion under which the traditional method of Book-building proceeds with IPOs, and further encouraged by the disaffection of several markets towards this method after the years 1999-2000, Gaël Giraud has a patent in the United-States regarding a new e-auction method according to which both the interests of the issuing corporate will be defended, as well as those of the first buyers of its shares.  This specific e-auction provides indeed a transparent forecast of the market price of the paper to be issued. It is the reflexion underlying this innovative work that will be shared during the lectures at ESCP.

Une dynamique hors équilibre calculable.
General equilibrium theory (which lies at the heart of most quantitative economic theories today) does not have yet a proper model for the out-of-equilibrium dynamics of an economy --- although this question has been officially put on the research calendar of many scholars almost fifty years ago. A number of theories are therefore forced to rely to the paradoxical assumption that an economy is always-already at equilibrium and will never leave it whatever being the external shocks it might encounter…  Going back to this open problem, Gaël Giraud is currently working on a computable out-of-equilibrium dynamics that shares the following properties : 1) Existence of solution trajectories is guaranteed under weaker conditions than those guaranteeing the existence of a Walras equilibrium ; 2) Generically, the solution trajectory is unique, piecewise smooth, and converges to some infinitesimal price equilibrium ; 3) For a class of economies that is much broader than the one usually under scrutiny in computable general equilibrium theory, each solution trajectory can be effectively computed (via Lemke’s algorithm) ; 4) Money is neither neutral on the short- nor on the long-run, although a localized version of the quantity theory of money can be written ; 5) Under-employment may appear along a solution trajectory and can be characterized as ``Classical’’, `Keynesian’’… This work in progress is done together with Céline Rochon and Dimitrios Tsomocos (Ben Saïd Business School , Oxford) as well as with Nguyen Hung (Paris-1). Around ten papers should appear soon as a by-product of this research.

Publications