The aim of the paper is to analyze the impact of heterogeneous beliefs in an otherwise standard competitive complete market economy. The construction of a consensus probability belief, as well as a consensus consumer, are shown to be valid modulo an aggregation bias, which takes the form of a...

We provide a price characterization of efficient contingent claims - that is, chosen by at least a rational agent - in multiperiod economies with market frictions. Frictions include market incompleteness, transaction costs, short-selling, and borrowing costs. We characterize the inefficiency...

We study comparative statics of Nth-degree risk increases within a large class of problems that involve bidimensional payoffs and additive or multiplicative risks. We establish necessary and sufficient conditions for unambiguous impact of Nth-degree risk increases on optimal decision making. We...

Why do investors keep different opinions even though they learn from their own failures and successes? Why do investors keep different opinions even though they observe each other and learn from their relative failures and successes? We analyze beliefs dynamics when beliefs result from a very...

We consider the problem of valuing European options in a complete market but with incomplete data. Typically, when the underlying asset dynamics is not specified, the martingale probability measure is unknown. Given a consensus on the actual distribution of the underlying price at maturity, we...

In this paper, we show that behavioral features can be obtained at a group level when the individuals of the group are heterogeneous enough. More precisely, starting from a standard model of Pareto optimal allocations, with expected utility maximizers and exponential dis- counting, but allowing...

In this paper we establish an index formula for a marginal pricing production economy and we prove the uniqueness of the equilibrium under a monotonicity assumption on the excess demand function and the local second order sufficient conditions for profit maximization. Our result generalizes...

S. Kusuoka [K 01, Theorem 4] gave an interesting dual characterizationof law invariant coherent risk measures, satisfying the Fatou property.The latter property was introduced by F. Delbaen [D 02]. In thepresent note we extend Kusuoka's characterization in two directions, thefirst one being...

In this note, we consider an economy with heterogeneous agents, differing by their time preference rate and by their beliefs. We show that at the Pareto optimum, the representative agent exhibits interesting behavioral properties. More precisely, starting from a standard model with expected...

In this paper we study some foundational issues in the theory of asset pricing with market frictions. We model market frictions by letting the set of marketed contingent claims (the opportunity set) be a convex set, and the pricing rule at which these claims are available be convex. This is the...