We compare the optimal trading strategy of an informed speculator when he can trade ahead of incoming news (is "fast"), versus when he cannot (is "slow"). We find that speed matters: the fast speculator's trades account for a larger fraction of trading volume, and are more correlated with...

French Abstract: Quelles sont les conséquences en matière de bien-être d'une meilleure diffusion de l'information financière parmi les spéculateurs? Pour traiter cette question, nous considérons un marché où des agents non informés échangent pour un motif de partage de risque avec des...

One apparent reason for deferring a decision – abstaining from choosing, leaving the decision open to be taken by someone else, one’s later self, or nature – is for lack of sufficient confidence in the relevant beliefs. This paper develops an axiomatic theory of decision in situations...

Cet article expose la problématique de la volatilité des prix des matières premières, montre quels sont les moyens pour s’en protéger et explique comment les employer. Les instruments de couverture sont présentés en première section, en distinguant le type de besoin auquel ils...

Using Consensus Forecasts monthly surveys, we show that experts' interest rate expectations in the Eurofranc market do not verify the rational expectations hypothesis. Instead, these expectations are found to be generated by a mixed process combining the traditional adaptive, regressive and...

This survey appears in extension of a previous exploratory survey (Bouraoui, 2008) dedicated to the impact of stock spams on volumes. The interest of the present research is to study the impact on stock prices while taking into account the evolution of volatility over time through a GARCH (1,1)...

(VF)Afin de comprendre pourquoi une banque décide la mise en faillite ou au contraire le soutien de son client en défaut de paiement, nous proposons une relecture de modèles issus de champs théoriques distincts. La littérature consacrée à la résolution des crises financières montre que...

Developing a model with a switching mechanism, we show how complex dynamics can be generated even though heterogeneity arises among agents with the same trading rules (fundamentalists). We assume that there are two experts which are imitated by other operators. We show that (i) market...