Price asymmetries and the path dependence of market power: Evidence from the U.S. airline industry

This paper uncovers price asymmetries across oligopolistic and monopolistic markets that are seemingly identical in structure but different in competitive history. This is done by identifying “quiet life” markets that have not (yet) experienced a change in structure, and “non-quiet life” markets that have been disrupted by firm entry and/or exit. Using a long panel dataset from the U.S. airline industry, we find that quiet life duopolies price significantly higher than duopolies that come about by entry in monopoly, and that quiet life monopolies price significantly lower than monopolies that come about by exit in duopoly. We show that the path towards a particular market structure matters for the determination of prices and explore several mechanisms that likely explain the price asymmetries, including engagement in anticompetitive behaviour, adjustment behaviour to market structure changes, and the cost heterogeneity of competing firms.