This discussion paper resulted in a publication in <A HREF="http://www.sciencedirect.com/science/article/pii/S019126151200063X#"<I>Transportation Research B: Methodological</I></A>, 2012, 46(8), 971-983.<P> We study road supply by competing firms between a single origin and destination. In previous studies, firms simultaneously set their tolls and capacities while taking the actions...</p></a>

This paper models the possible effects over the market price of a homogeneous good when there is a merger. The analysis will be made with two scenarios: (i) using technologies homogenous between firms, (ii) and with any degree of heterogeneity. It is assumed an linear inverse function of demand...

A `collusion puzzle' exists by which, even though increasing the number of firms reduces the ability to tacitly collude, and leads to a collapse in collusion in experimental markets with four or more firms, in natural markets there are such numbers of firms colluding successfully. We present an...

Gum arabic is mainly produced from two Acacias that are found in the gum belt of Sub-Saharan Africa. These are Acacia senegal that produces high quality gum and Acacia seyal that produces low quality gum. In recent years the gum market structure has changed and Sudan lost its near monopoly...

We show that if firms in an industry engage in third-degree price discrimination, the number of firms in the free-entry equilibrium may be inefficiently low. This result is obtained even with set up costs and a price above marginal cost. We discuss the relevant implications that our result has...

The main purpose of this paper is to model the role of the narco-insurgency in the structure and functioning of the colombian cocaine market. The narco-insurgency gets important profits from this market by controlling the land for producing coca-leaf, and the production of inputs for trading...