Spatial structure and network behaviour of strategic airline groups: A comparison between Europe and the United States

The Gini-index has gained in legitimacy when measuring traffic distributions of air traffic as compared to other more established measures, such as Herfindahl's. In order to render the index more meaningful for policy-makers, a partial decomposition into strategic groups of airlines along distinct geopolitical scopes of air traffic is suggested. Air traffic across airports is considered an aggregate of complex networks that are subject to multiple constraints, such as geopolitics or technology. A multi-layered analytic approach accounts for network operators as economic agents that behave in strategic ways within these constraints. Our approach allows for comparing traffic distributions in Europe with that of the US and, in particular, introduces a normative component by isolating patterns in airlines’ strategies that are likely to induce different degrees of spatial concentration and balanced traffic distributions within these common markets.