Deltas, Salvo and Vasconcelos (2011) develop a model of geographically separated markets with differentiated goods in which collusion (or merger to monopoly), by restricting trade relative to duopolistic competition, is beneficial for society and can be beneficial for consumers. In this chapter,...

I begin by fitting traditional gravity equations to document that regional flows in the Brazilian cement industry exhibit gravity-like structure, with cement trade decaying sharply in distance traveled. I then show that this large distance effect owes to firms' strategic behavior over and above...

That collusion among sellers hurts buyers is a central tenet in economics. We provide an oligopoly model in which collusion can raise consumer surplus. A differentiated-product duopoly operates in two geographically-separated markets. Each market is home to a single firm, but can import, at a...

This paper argues that large distance and border effects on trade flows in some industries might be a result of the (explicitly or tacitly) collusive division of geographic markets. A simple spatial oligopoly setting demonstrates how goods can travel shorter distances, or trade between regions...