This discussion paper resulted in a publication in the 'SIAM Journal on Optimization', 2006, 16, 854-870. <P> It is well known that an upper semi-continuous compact- and convex-valued mapping fi from a nonempty compact and convex set X to the Euclidean space of which X is a subset has at least one...</p>

In a standard general equilibrium model it is assumed that there are no price restictionsand that prices adjust infinitely fast to their equilibrium values. In this paper the set ofadmissible prices is allowed to be an arbitrary convex set. For such an arbitrary set it cannotbe guaranteed that...

Any function from a non-empty polytope into itself that is locally gross direction preserving is shown to have the fixed point property. Brouwer's fixed point theorem for continuous functions is a special case. We discuss the application of the result in the area of non-cooperative game...</p>

We study how players in a local interaction hawk dove game will learn, if they can either imitate the most succesful player in the neighborhood or play a best reply versus the opponent's previous action. From simulations it appears that each learning strategy will be used, because each performs...

This discussion paper resulted in a forthcoming article in the <I>Journal of Economic Behavior & Organization</I>.<P> This paper characterizes the set of equilibrium networks in the two-way flow model of network formation with small decay, and this for all increasing benefit functions of the players. We...</p></i>

This paper studies network formation in settings where players are heterogeneous with respect to benefits as well as the costs of forming links. Our results demonstrate that centrality, center-sponsorship and short network diameter are robust features of equilibrium networks. We find that in a...

This paper studies the incentives to merge in a Bertrand competition model where firms sell differentiatedproducts and consumers search for satisfactory deals. In the pre-merger symmetricequilibrium, the probability that a firm is the next one to be visited by a consumer is equal acrossfirms not...

This paper investigates the asymptotic properties of the ordinary least squares (OLS) estimator of structural parameters in a stylised macroeconomic model in which agents are boundedly rational and use an adaptive learning rule to form expectations of the endogenous variable. In particular, when...

The search literature assumes that consumers know which firms sell products they are looking for, but are unaware of the particular variety and the prices at which each firm sells. In this paper, we consider the situation where consumers are uncertain whether a firm carries the product at all by...

We model the idea that when consumers search for products, they first visit the firm whose advertising is more salient. The gains a firm derives from being visited early increase in search costs, so equilibrium advertising increases as search costs rise. This may result in lower firm profits...