Biconcavity is a simple condition on inverse demand that corresponds to the ordinary concept of concavity after simultaneous parameterized transformations of price and quantity. The notion is employed here in the framework of the homogeneous-good Cournot model with potentially heterogeneous...

We introduce a simple two-stage game of endogenous network formation and information sharing for reasoning about the optimal design of social networks like Facebook or Google+. We distinguish between unilateral and bilateral connections and between targeted and collective information sharing....

Optimal rank-order tournaments have traditionally been studied using a first-order approach. The present analysis relies instead on the construction of an "upper envelope" over all incentive compatibility conditions. lt turns out that the first-order approach is not innocuous. For example, in...

Under the assumption of normally distributed returns, we analyze whether the Cumulative Prospect Theory of Tversky and Kahneman (1992) is consistent with the Capital Asset Pricing Model. We find that in every financial market equilibrium the Security Market Line Theorem holds. However, under the...

The N-firm Cournot model with general technologies is reviewed to derive generalized and unified conditions for existence of a pure strategy Nash equilibrium. Tight conditions are formulated alternatively (i) in terms of concavity of two-sided transforms of inverse demand, or (ii) as linear...

In the incomplete markets model with numeraire asset and a single con- sumption good we show that, even with homothetic preferences, on compact sets of prices Continuity, Walras' identity and Homogeneity characterize the properties of market excess demand.This result is proved by an extension of...

The purpose of this paper is to give a global characterization of excess demand functions in a two period exchange economy with incomplete real asset markets. We show that continuity, homogeneity and Walras’ law characterize the aggregate excess demand functions on any compact price set which...

The goal of this paper is to introduce and illustrate a new approach to the stability analysis of sample-paths of nonlinear stochastic economic models with non-stationary components. We place our study within the mathematical theory of random dynamical systems and apply the concept of a random...

This paper presents a complete analysis of a stochastic version of the Solow growth model in which all parameters are ergodic random variables. Applying random dynamical systems theory, we prove that the dynamics and, in particular, the long-run behavior is uniquely determined by a globally...

In the standard CAPM with a riskless asset we give a sufficient condition for uniqueness. This condition is a joint restriction on the agents' endowments and their preferences which is compatible with non-increasing absolute risk aversion and which is in particular satisfied with constant...