This paper revisits the conventional doctrine that "it is easier to collude among equals", applied in the context of vertically related markets. In a differentiated duopoly model, we study how cost-based access price regulation may hinder the sustainability of tacit collusion. © 2009 Elsevier B.V. All rights reserved.
Baranes, E., & Poudou, J. C. (2010). Cost-based access regulation and collusion in a differentiated duopoly. Economics Letters, 106(3), 172–176. https://doi.org/10.1016/j.econlet.2009.11.012